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Bijlsma A, Birza EE, Pimentel TC, Maranus JPM, van Gaans MJJM, Lozeman-van T Klooster JG, Baars AJM, Achterberg EJM, Lesscher HMB, Wierenga CJ, Vanderschuren LJMJ. Opportunities for risk-taking during play alters cognitive performance and prefrontal inhibitory signalling in rats of both sexes. Eur J Neurosci 2024; 59:2748-2765. [PMID: 38511534 DOI: 10.1111/ejn.16313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2023] [Accepted: 02/22/2024] [Indexed: 03/22/2024]
Abstract
Social play behaviour is a rewarding activity that can entail risks, thus allowing young individuals to test the limits of their capacities and to train their cognitive and emotional adaptability to challenges. Here, we tested in rats how opportunities for risk-taking during play affect the development of cognitive and emotional capacities and medial prefrontal cortex (mPFC) function, a brain structure important for risk-based decision making. Male and female rats were housed socially or social play-deprived (SPD) between postnatal day (P)21 and P42. During this period, half of both groups were daily exposed to a high-risk play environment. Around P85, all rats were tested for cognitive performance and emotional behaviour after which inhibitory currents were recorded in layer 5 pyramidal neurons in mPFC slices. We show that playing in a high-risk environment altered cognitive flexibility in both sexes and improved behavioural inhibition in males. High-risk play altered anxiety-like behaviour in the elevated plus maze in males and in the open field in females, respectively. SPD affected cognitive flexibility in both sexes and decreased anxiety-like behaviour in the elevated plus maze in females. We found that synaptic inhibitory currents in the mPFC were increased in male, but not female, rats after high-risk play, while SPD lowered prefrontal cortex (PFC) synaptic inhibition in both sexes. Together, our data show that exposure to risks during play affects the development of cognition, emotional behaviour and inhibition in the mPFC. Furthermore, our study suggests that the opportunity to take risks during play cannot substitute for social play behaviour.
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Affiliation(s)
- Ate Bijlsma
- Department of Biology, Faculty of Science, Utrecht University, Utrecht, The Netherlands
- Department of Population Health Sciences, Section Animals in Science and Society, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Evelien E Birza
- Department of Population Health Sciences, Section Animals in Science and Society, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Tara C Pimentel
- Department of Population Health Sciences, Section Animals in Science and Society, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Janneke P M Maranus
- Department of Population Health Sciences, Section Animals in Science and Society, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Marieke J J M van Gaans
- Department of Population Health Sciences, Section Animals in Science and Society, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - José G Lozeman-van T Klooster
- Department of Population Health Sciences, Section Animals in Science and Society, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Annemarie J M Baars
- Department of Population Health Sciences, Section Animals in Science and Society, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - E J Marijke Achterberg
- Department of Population Health Sciences, Section Animals in Science and Society, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Heidi M B Lesscher
- Department of Population Health Sciences, Section Animals in Science and Society, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
| | - Corette J Wierenga
- Department of Biology, Faculty of Science, Utrecht University, Utrecht, The Netherlands
- Donders Institute and Faculty of Science, Radboud University, Nijmegen, The Netherlands
| | - Louk J M J Vanderschuren
- Department of Population Health Sciences, Section Animals in Science and Society, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands
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Berry JA, Guhle DC, Davis RL. Active forgetting and neuropsychiatric diseases. Mol Psychiatry 2024:10.1038/s41380-024-02521-9. [PMID: 38532011 DOI: 10.1038/s41380-024-02521-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Revised: 03/04/2024] [Accepted: 03/06/2024] [Indexed: 03/28/2024]
Abstract
Recent and pioneering animal research has revealed the brain utilizes a variety of molecular, cellular, and network-level mechanisms used to forget memories in a process referred to as "active forgetting". Active forgetting increases behavioral flexibility and removes irrelevant information. Individuals with impaired active forgetting mechanisms can experience intrusive memories, distressing thoughts, and unwanted impulses that occur in neuropsychiatric diseases. The current evidence indicates that active forgetting mechanisms degrade, or mask, molecular and cellular memory traces created in synaptic connections of "engram cells" that are specific for a given memory. Combined molecular genetic/behavioral studies using Drosophila have uncovered a complex system of cellular active-forgetting pathways within engram cells that is regulated by dopamine neurons and involves dopamine-nitric oxide co-transmission and reception, endoplasmic reticulum Ca2+ signaling, and cytoskeletal remodeling machinery regulated by small GTPases. Some of these molecular cellular mechanisms have already been found to be conserved in mammals. Interestingly, some pathways independently regulate forgetting of distinct memory types and temporal phases, suggesting a multi-layering organization of forgetting systems. In mammals, active forgetting also involves modulation of memory trace synaptic strength by altering AMPA receptor trafficking. Furthermore, active-forgetting employs network level mechanisms wherein non-engram neurons, newly born-engram neurons, and glial cells regulate engram synapses in a state and experience dependent manner. Remarkably, there is evidence for potential coordination between the network and cellular level forgetting mechanisms. Finally, subjects with several neuropsychiatric diseases have been tested and shown to be impaired in active forgetting. Insights obtained from research on active forgetting in animal models will continue to enrich our understanding of the brain dysfunctions that occur in neuropsychiatric diseases.
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Affiliation(s)
- Jacob A Berry
- Department of Biological Sciences, University of Alberta, Edmonton, AL, T6G 2E9, Canada.
| | - Dana C Guhle
- Department of Biological Sciences, University of Alberta, Edmonton, AL, T6G 2E9, Canada
| | - Ronald L Davis
- Department of Neuroscience, UF Scripps Institute for Biomedical Innovation & Technology, 130 Scripps Way, Jupiter, FL, 33458, USA.
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Li S, May C, Pang TY, Churilov L, Hannan AJ, Johnson KA, Burrows EL. Mice with an autism-associated R451C mutation in neuroligin-3 show intact attention orienting but atypical responses to methylphenidate and atomoxetine in the mouse-Posner task. Psychopharmacology (Berl) 2024; 241:555-567. [PMID: 38170320 DOI: 10.1007/s00213-023-06520-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/27/2023] [Accepted: 12/18/2023] [Indexed: 01/05/2024]
Abstract
RATIONALE Atypical attention orienting has been associated with some autistic symptoms, but the neural mechanisms remain unclear. The human Posner task, a classic attention orienting paradigm, was recently adapted for use with mice, supporting the investigation of the neurobiological underpinnings of atypical attention orienting in preclinical mouse models. OBJECTIVE The current study tested mice expressing the autism-associated R451C gene mutation in neuroligin-3 (NL3) on the mouse-Posner (mPosner) task. METHODS NL3R451C and wild-type (WT) mice were trained to respond to a validly or invalidly cued target on a touchscreen. The cue was a peripheral non-predictive flash in the exogenous task and a central spatially predictive image in the endogenous task. The effects of dopaminergic- and noradrenergic-modulating drugs, methylphenidate and atomoxetine, on task performance were assessed. RESULTS In both tasks, mice were quicker and more accurate in the validly versus invalidly cued trials, consistent with results in the human Posner task. NL3R451C and WT mice showed similar response times and accuracy but responded differently when treated with methylphenidate and atomoxetine. Methylphenidate impaired exogenous attention disengagement in NL3R451C mice but did not significantly affect WT mice. Atomoxetine impaired endogenous orienting in WT mice but did not significantly affect NL3R451C mice. CONCLUSIONS NL3R451C mice demonstrated intact attention orienting but altered responses to the pharmacological manipulation of the dopaminergic and noradrenergic networks. These findings expand our understanding of the NL3R451C mutation by suggesting that this mutation may lead to selective alterations in attentional processes.
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Affiliation(s)
- Shuting Li
- Melbourne School of Psychological Sciences, The University of Melbourne, Parkville, VIC, 3010, Australia.
- Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, VIC, 3052, Australia.
| | - Carlos May
- Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, VIC, 3052, Australia
| | - Terence Y Pang
- Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, VIC, 3052, Australia
- Department of Anatomy and Neuroscience, The University of Melbourne, Parkville, VIC, 3010, Australia
| | - Leonid Churilov
- Melbourne Medical School, The University of Melbourne, Parkville, VIC, 3010, Australia
| | - Anthony J Hannan
- Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, VIC, 3052, Australia
- Department of Anatomy and Neuroscience, The University of Melbourne, Parkville, VIC, 3010, Australia
| | - Katherine A Johnson
- Melbourne School of Psychological Sciences, The University of Melbourne, Parkville, VIC, 3010, Australia
| | - Emma L Burrows
- Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Parkville, VIC, 3052, Australia.
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Mohd Sahini SN, Mohd Nor Hazalin NA, Srikumar BN, Jayasingh Chellammal HS, Surindar Singh GK. Environmental enrichment improves cognitive function, learning, memory and anxiety-related behaviours in rodent models of dementia: Implications for future study. Neurobiol Learn Mem 2024; 208:107880. [PMID: 38103676 DOI: 10.1016/j.nlm.2023.107880] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Revised: 11/27/2023] [Accepted: 12/07/2023] [Indexed: 12/19/2023]
Abstract
Environmental enrichment (EE) is a process of brain stimulation by modifying the surroundings, for example, by changing the sensory, social, or physical conditions. Rodents have been used in such experimental strategies through exposure to diverse physical, social, and exploration conditions. The present study conducted an extensive analysis of the existing literature surrounding the impact of EE on dementia rodent models. The review emphasised the two principal aspects that are very closely related to dementia: cognitive function (learning and memory) as well as psychological factors (anxiety-related behaviours such as phobias and unrealistic worries). Also highlighted were the mechanisms involved in the rodent models of dementia showing EE effects. Two search engines, PubMed and Science Direct, were used for data collection using the following keywords: environmental enrichment, dementia, rodent model, cognitive performance, and anxiety-related behaviour. Fifty-five articles were chosen depending on the criteria for inclusion and exclusion. The rodent models with dementia demonstrated improved learning and memory in the form of hampered inflammatory responses, enhanced neuronal plasticity, and sustained neuronal activity. EE housing also prevented memory impairment through the prevention of amyloid beta (Aβ) seeding formation, an early stage of Aβ plaque formation. The rodents subjected to EE were observed to present increased exploratory activity and exert less anxiety-related behaviour, compared to those in standard housing. However, some studies have proposed that EE intervention through exercise would be too mild to counteract the anxiety-related behaviour and risk assessment behaviour deficits in the Alzheimer's disease rodent model. Future studies should be conducted on old-aged rodents and the duration of EE exposure that would elicit the greatest benefits since the existing studies have been conducted on a range of ages and EE durations. In summary, EE had a considerable effect on dementia rodent models, with the most evident being improved cognitive function.
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Affiliation(s)
- Siti Norhafizah Mohd Sahini
- Department of Pharmaceutical Life Sciences, Faculty of Pharmacy, Universiti Teknologi MARA (UiTM), Selangor Branch, Puncak Alam Campus, 42300 Bandar Puncak Alam, Selangor, Malaysia; Outpatient Pharmacy Department, Hospital Raja Permaisuri Bainun, 30450 Ipoh, Perak, Malaysia
| | - Nurul Aqmar Mohd Nor Hazalin
- Department of Pharmaceutical Life Sciences, Faculty of Pharmacy, Universiti Teknologi MARA (UiTM), Selangor Branch, Puncak Alam Campus, 42300 Bandar Puncak Alam, Selangor, Malaysia; Integrative Pharmacogenomics Institute (iPROMiSE), Level 7, FF3, Universiti Teknologi MARA, Selangor Branch, Puncak Alam Campus, 42300 Bandar Puncak Alam, Selangor, Malaysia
| | - Bettadapura N Srikumar
- Department of Neurophysiology, National Institute of Mental Health and Neuro Sciences (NIMHANS), Hosur Road, Bengaluru - 560029, India
| | - Hanish Singh Jayasingh Chellammal
- Department of Pharmacology and Pharmaceutical Chemistry, Faculty of Pharmacy, Universiti Teknologi MARA (UiTM), Selangor Branch, Puncak Alam Campus, 42300 Bandar Puncak Alam, Selangor, Malaysia; Brain Degeneration and Therapeutics Group, Universiti Teknologi MARA (UiTM), 40450 Shah Alam, Selangor, Malaysia
| | - Gurmeet Kaur Surindar Singh
- Department of Pharmaceutical Life Sciences, Faculty of Pharmacy, Universiti Teknologi MARA (UiTM), Selangor Branch, Puncak Alam Campus, 42300 Bandar Puncak Alam, Selangor, Malaysia; Brain Degeneration and Therapeutics Group, Universiti Teknologi MARA (UiTM), 40450 Shah Alam, Selangor, Malaysia.
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Farmer AL, Lewis MH. Reduction of restricted repetitive behavior by environmental enrichment: Potential neurobiological mechanisms. Neurosci Biobehav Rev 2023; 152:105291. [PMID: 37353046 DOI: 10.1016/j.neubiorev.2023.105291] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2023] [Revised: 06/04/2023] [Accepted: 06/19/2023] [Indexed: 06/25/2023]
Abstract
Restricted repetitive behaviors (RRB) are one of two diagnostic criteria for autism spectrum disorder and common in other neurodevelopmental and psychiatric disorders. The term restricted repetitive behavior refers to a wide variety of inflexible patterns of behavior including stereotypy, self-injury, restricted interests, insistence on sameness, and ritualistic and compulsive behavior. However, despite their prevalence in clinical populations, their underlying causes remain poorly understood hampering the development of effective treatments. Intriguingly, numerous animal studies have demonstrated that these behaviors are reduced by rearing in enriched environments (EE). Understanding the processes responsible for the attenuation of repetitive behaviors by EE should offer insights into potential therapeutic approaches, as well as shed light on the underlying neurobiology of repetitive behaviors. This review summarizes the current knowledge of the relationship between EE and RRB and discusses potential mechanisms for EE's attenuation of RRB based on the broader EE literature. Existing gaps in the literature and future directions are also discussed.
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Affiliation(s)
- Anna L Farmer
- Department of Psychology, University of Florida, Gainesville, FL, USA.
| | - Mark H Lewis
- Department of Psychology, University of Florida, Gainesville, FL, USA; Department of Psychiatry, University of Florida, Gainesville, FL, USA
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Bennett D, Nakamura J, Vinnakota C, Sokolenko E, Nithianantharajah J, van den Buuse M, Jones NC, Sundram S, Hill R. Mouse Behavior on the Trial-Unique Nonmatching-to-Location (TUNL) Touchscreen Task Reflects a Mixture of Distinct Working Memory Codes and Response Biases. J Neurosci 2023; 43:5693-5709. [PMID: 37369587 PMCID: PMC10401633 DOI: 10.1523/jneurosci.2101-22.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Revised: 04/28/2023] [Accepted: 06/02/2023] [Indexed: 06/29/2023] Open
Abstract
The trial-unique nonmatching to location (TUNL) touchscreen task shows promise as a translational assay of working memory (WM) deficits in rodent models of autism, ADHD, and schizophrenia. However, the low-level neurocognitive processes that drive behavior in the TUNL task have not been fully elucidated. In particular, it is commonly assumed that the TUNL task predominantly measures spatial WM dependent on hippocampal pattern separation, but this proposition has not previously been tested. In this project, we tested this question using computational modeling of behavior from male and female mice performing the TUNL task (N = 163 across three datasets; 158,843 trials). Using this approach, we empirically tested whether TUNL behavior solely measured retrospective WM, or whether it was possible to deconstruct behavior into additional neurocognitive subprocesses. Overall, contrary to common assumptions, modeling analyses revealed that behavior on the TUNL task did not primarily reflect retrospective spatial WM. Instead, behavior was best explained as a mixture of response strategies, including both retrospective WM (remembering the spatial location of a previous stimulus) and prospective WM (remembering an anticipated future behavioral response) as well as animal-specific response biases. These results suggest that retrospective spatial WM is just one of a number of cognitive subprocesses that contribute to choice behavior on the TUNL task. We suggest that findings can be understood within a resource-rational framework, and use computational model simulations to propose several task-design principles that we predict will maximize spatial WM and minimize alternative behavioral strategies in the TUNL task.SIGNIFICANCE STATEMENT Touchscreen tasks represent a paradigm shift for assessment of cognition in nonhuman animals by automating large-scale behavioral data collection. Their main relevance, however, depends on the assumption of functional equivalence to cognitive domains in humans. The trial-unique, delayed nonmatching to location (TUNL) touchscreen task has revolutionized the study of rodent spatial working memory. However, its assumption of functional equivalence to human spatial working memory is untested. We leveraged previously untapped single-trial TUNL data to uncover a novel set of hierarchically ordered cognitive processes that underlie mouse behavior on this task. The strategies used demonstrate multiple cognitive approaches to a single behavioral outcome and the requirement for more precise task design and sophisticated data analysis in interpreting rodent spatial working memory.
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Affiliation(s)
- Daniel Bennett
- School of Psychological Sciences, Monash University, Melbourne, Victoria 3180, Australia
| | - Jay Nakamura
- Department of Psychiatry, Monash University, Melbourne, Victoria 3180, Australia
- Laboratory for Molecular Mechanisms of Brain Development, RIKEN Center for Brain Science, Saitama, Japan, 351-0198
| | - Chitra Vinnakota
- Department of Psychiatry, Monash University, Melbourne, Victoria 3180, Australia
| | - Elysia Sokolenko
- Discipline of Anatomy and Pathology, School of Biomedicine, University of Adelaide, Adelaide, South Australia 5005, Australia
| | | | - Maarten van den Buuse
- School of Psychology and Public Health, La Trobe University, Melbourne, Victoria 3086, Australia
| | - Nigel C Jones
- Department of Neuroscience, Central Clinical School, Monash University, Melbourne, Victoria 3004, Australia
- Department of Neurology, Alfred Hospital, Commercial Road, Melbourne, Victoria 3004, Australia
- Department of Medicine, Royal Melbourne Hospital, University of Melbourne, Melbourne, Victoria 3052, Australia
| | - Suresh Sundram
- Department of Psychiatry, Monash University, Melbourne, Victoria 3180, Australia
- Mental Health Program, Monash Health, Clayton, Victoria 3168, Australia
| | - Rachel Hill
- Department of Psychiatry, Monash University, Melbourne, Victoria 3180, Australia
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Ikuta K, Joho D, Kakeyama M, Matsumoto M. Bifidobacterium animalis subsp. lactis and arginine mixture intake improves cognitive flexibility in mice. Front Nutr 2023; 10:1164809. [PMID: 37346910 PMCID: PMC10279864 DOI: 10.3389/fnut.2023.1164809] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2023] [Accepted: 05/09/2023] [Indexed: 06/23/2023] Open
Abstract
The relationship between intestinal microbiota and cognitive function has been investigated as one of the major topics within the intestinal microbiota-gut-brain axis. Although an increasing number of studies have demonstrated an improvement in learning and memory when using probiotics or prebiotics, to date, there are no studies that target the cognitive flexibility observed in the early stages of several neuropsychiatric diseases, including dementia. We have recently developed a novel behavioral task using the touchscreen operant system to assess cognitive flexibility. We found that the disruption of the intestinal microbiota in mice induced a decline in cognitive flexibility. In the present study, we investigated the effects of treatments consisting of Bifidobacterium animalis subsp. lactis and arginine (Bifal + Arg), which promote the production of intestinal bacterial polyamine, on cognitive flexibility in the mouse model. Male C57BL6 mice orally treated with Bifal + Arg three times a week gradually decreased the 1st-choice incorrect diagonal rate with repeated reversals compared with the control group. Furthermore, in serial reversal phases, Bifal + Arg-treated mice shifted to the behavior of choosing a new correct spot more quickly after the reversal, and this was faster with repeated reversals. These results indicate that this treatment adapts to change and improves cognitive flexibility. This is the first report to show that intestinal environmental control, including probiotics and prebiotics, improves cognitive flexibility in mice.
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Affiliation(s)
- Kayo Ikuta
- Dairy Science and Technology Institute, Kyodo Milk Industry Co., Ltd., Tokyo, Japan
| | - Daisuke Joho
- Laboratory for Environmental Brain Science, Faculty of Human Sciences, Waseda University, Tokorozawa, Japan
| | - Masaki Kakeyama
- Laboratory for Environmental Brain Science, Faculty of Human Sciences, Waseda University, Tokorozawa, Japan
- Research Institute for Environmental Medical Sciences, Comprehensive Research Organization, Waseda University, Tokorozawa, Japan
| | - Mitsuharu Matsumoto
- Dairy Science and Technology Institute, Kyodo Milk Industry Co., Ltd., Tokyo, Japan
- Research Institute for Environmental Medical Sciences, Comprehensive Research Organization, Waseda University, Tokorozawa, Japan
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Gattas S, Collett HA, Huff AE, Creighton SD, Weber SE, Buckhalter SS, Manning SA, Ryait HS, McNaughton BL, Winters BD. A rodent obstacle course procedure controls delivery of enrichment and enhances complex cognitive functions. NPJ SCIENCE OF LEARNING 2022; 7:21. [PMID: 36057661 PMCID: PMC9440923 DOI: 10.1038/s41539-022-00134-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Accepted: 06/13/2022] [Indexed: 06/15/2023]
Abstract
Enrichment in rodents affects brain structure, improves behavioral performance, and is neuroprotective. Similarly, in humans, according to the cognitive reserve concept, enriched experience is functionally protective against neuropathology. Despite this parallel, the ability to translate rodent studies to human clinical situations is limited. This limitation is likely due to the simple cognitive processes probed in rodent studies and the inability to control, with existing methods, the degree of rodent engagement with enrichment material. We overcome these two difficulties with behavioral tasks that probe, in a fine-grained manner, aspects of higher-order cognition associated with deterioration with aging and dementia, and a new enrichment protocol, the 'Obstacle Course' (OC), which enables controlled enrichment delivery, respectively. Together, these two advancements will enable better specification (and comparisons) of the nature of impairments in animal models of complex mental disorders and the potential for remediation from various types of intervention (e.g., enrichment, drugs). We found that two months of OC enrichment produced substantial and sustained enhancements in categorization memory, perceptual object invariance, and cross-modal sensory integration in mice. We also tested mice on behavioral tasks previously shown to benefit from traditional enrichment: spontaneous object recognition, object location memory, and pairwise visual discrimination. OC enrichment improved performance relative to standard housing on all six tasks and was in most cases superior to conventional home-cage enrichment and exercise track groups.
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Affiliation(s)
- Sandra Gattas
- Department of Electrical Engineering and Computer Science, University of California, Irvine, CA, USA.
- Medical Scientist Training Program, University of California, Irvine, CA, USA.
| | - Heather A Collett
- Department of Psychology and Collaborative Neuroscience Program, University of Guelph, Guelph, ON, Canada
| | - Andrew E Huff
- Department of Psychology and Collaborative Neuroscience Program, University of Guelph, Guelph, ON, Canada
| | - Samantha D Creighton
- Department of Psychology and Collaborative Neuroscience Program, University of Guelph, Guelph, ON, Canada
| | - Siobhon E Weber
- Department of Psychology and Collaborative Neuroscience Program, University of Guelph, Guelph, ON, Canada
| | | | - Silas A Manning
- Department of Psychology and Collaborative Neuroscience Program, University of Guelph, Guelph, ON, Canada
| | - Hardeep S Ryait
- Canadian Centre for Behavioural Neuroscience, University of Lethbridge, Lethbridge, AB, Canada
| | - Bruce L McNaughton
- Canadian Centre for Behavioural Neuroscience, University of Lethbridge, Lethbridge, AB, Canada.
- Department of Neurobiology and Behavior, University of California, Irvine, CA, USA.
| | - Boyer D Winters
- Department of Psychology and Collaborative Neuroscience Program, University of Guelph, Guelph, ON, Canada.
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9
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Cheng ST, Liu S, Ou-Yang B, Dai XY, Cheng L. Specific Effects of Characteristics of Enriched Environment on Innovative Problem Solving by Animals. Psychol Sci 2022; 33:1097-1111. [PMID: 35776087 DOI: 10.1177/09567976211070562] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Numerous studies have revealed that an enriched environment can enhance the survival-related behaviors and brain functions of animals. However, the effects and specific roles of the enrichment characteristics on animals' innovative capability, a cognitive ability crucial for survival in nature, are still not well known. In this study, we assigned mice to environment-manipulation groups (n = 15 each) to investigate the specific effects of environmental novelty (novel vs. familiar) and environmental complexity (complex vs. normal) on innovative problem solving and its possible neural mechanisms. Results showed that mice in only the novel-environment group performed better at innovative-problem-solving tasks and showed greater numbers of novel explorations and dopaminergic projections from the ventral tegmental area to the nucleus accumbens in the brain. These findings indicate that an enriched environment has the potential to promote the innovative capability of mice by enhancing their novel exploratory motivation, which depends on the novelty of the environment but not its complexity.
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Affiliation(s)
- Sha-Te Cheng
- School of Psychology, Central China Normal University.,Key Laboratory of Adolescent Cyberpsychology and Behavior, Ministry of Education, Central China Normal University
| | - Sha Liu
- School of Psychology, Central China Normal University.,Key Laboratory of Adolescent Cyberpsychology and Behavior, Ministry of Education, Central China Normal University
| | - Bo Ou-Yang
- School of Psychology, Central China Normal University.,Key Laboratory of Adolescent Cyberpsychology and Behavior, Ministry of Education, Central China Normal University
| | - Xin-Yu Dai
- School of Psychology, Central China Normal University.,Key Laboratory of Adolescent Cyberpsychology and Behavior, Ministry of Education, Central China Normal University
| | - Liang Cheng
- School of Psychology, Central China Normal University.,Key Laboratory of Adolescent Cyberpsychology and Behavior, Ministry of Education, Central China Normal University
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Salmani N, Nozari M, Parvan M, Amini-Sardouei S, Shabani M, Khaksari M, Ezzatabadipour M. Nicotine-conditioned place preference, reversal learning, and social interaction in MK-801-induced schizophrenia model: Effects of post-weaning enriched environment. Clin Exp Pharmacol Physiol 2022; 49:871-880. [PMID: 35622536 DOI: 10.1111/1440-1681.13674] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Revised: 01/22/2022] [Accepted: 05/24/2022] [Indexed: 11/30/2022]
Abstract
Based on the clinical observations of severe cognitive deficits in schizophrenia patients and the relationship between environmental parameters and the severity of schizophrenia symptoms, the present study investigated these parameters in an MK-801-induced schizophrenia model in rats. In addition to, it evaluated whether a post-weaning enriched environment (EE) would affect the nicotine-induced conditioned place preference (CPP) and the motor and cognitive deficits caused by MK-801 treatment. Male Wistar rat pups were injected peritoneally with MK-801 (1 mg/kg) on a daily basis between the 6th and the 10th postnatal days (P) and were exposed to either an enriched or a standard cage from P21 until the end of the experiments. The rats were evaluated in open-field and three-chamber social interaction tests. Moreover, spatial and reversal learning was assessed by the Morris water maze (MWM). Also, the animals were conditioned with 0.6 mg/kg nicotine and tested for CPP. Increased self-grooming, exploratory behavior, potentiated nicotine-CPP, and decreased social behaviors, delayed spatial learning and memory, and impaired reversal learning in the water maze were observed in the MK-801 treatment group. Housing in an EE improved cognitive and behavioral deficits associated with postnatal MK-801 treatment. The results suggested that neonatal N-methyl-D-aspartate (NMDA) receptor hypofunction may cause susceptibility to these behaviors and indicated the importance of environmental conditions in the development of schizophrenia and probably other neuropsychiatric disorders.
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Affiliation(s)
- Neda Salmani
- Department of Psychology, Zarand Branch, Islamic Azad University, Kerman, Iran
| | - Masoumeh Nozari
- Neuroscience Research Center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran
| | - Mahdieh Parvan
- Physiology Research Center, Institute of Basic and Clinical Physiology Sciences, Kerman University of Medical Sciences, Kerman, Iran
| | - Sara Amini-Sardouei
- Student Research Committee, Kerman University of Medical Sciences, Kerman, Iran
| | - Mohammad Shabani
- Neuroscience Research Center, Institute of Neuropharmacology, Kerman University of Medical Sciences, Kerman, Iran
| | - Mohammad Khaksari
- Endocrinology and Metabolism Research, and Physiology Research Centers, Kerman University of Medical Sciences, Kerman, Iran
| | - Massood Ezzatabadipour
- Anatomical Sciences Department, School of Medicine, Kerman University of Medical Sciences, Kerman, Iran
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11
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Zhao X, Erickson M, Mohammed R, Kentner AC. Maternal immune activation accelerates puberty initiation and alters mechanical allodynia in male and female C57BL6/J mice. Dev Psychobiol 2022; 64:e22278. [DOI: 10.1002/dev.22278] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 01/13/2022] [Accepted: 03/09/2022] [Indexed: 12/17/2022]
Affiliation(s)
- Xin Zhao
- School of Arts & Sciences, Health Psychology Program Massachusetts College of Pharmacy and Health Sciences Boston Massachusetts USA
| | - Mary Erickson
- School of Arts & Sciences, Health Psychology Program Massachusetts College of Pharmacy and Health Sciences Boston Massachusetts USA
| | - Ruqayah Mohammed
- School of Arts & Sciences, Health Psychology Program Massachusetts College of Pharmacy and Health Sciences Boston Massachusetts USA
| | - Amanda C. Kentner
- School of Arts & Sciences, Health Psychology Program Massachusetts College of Pharmacy and Health Sciences Boston Massachusetts USA
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12
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Effects of environmental enrichment on exploratory behavior, win-stay and lose-shift performance, motor sequence learning, and reversal learning during the three-lever operant task in mice. Behav Brain Res 2022; 429:113904. [DOI: 10.1016/j.bbr.2022.113904] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Revised: 03/29/2022] [Accepted: 04/19/2022] [Indexed: 11/22/2022]
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13
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Ryan TJ, Frankland PW. Forgetting as a form of adaptive engram cell plasticity. Nat Rev Neurosci 2022; 23:173-186. [PMID: 35027710 DOI: 10.1038/s41583-021-00548-3] [Citation(s) in RCA: 43] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/25/2021] [Indexed: 12/30/2022]
Abstract
One leading hypothesis suggests that memories are stored in ensembles of neurons (or 'engram cells') and that successful recall involves reactivation of these ensembles. A logical extension of this idea is that forgetting occurs when engram cells cannot be reactivated. Forms of 'natural forgetting' vary considerably in terms of their underlying mechanisms, time course and reversibility. However, we suggest that all forms of forgetting involve circuit remodelling that switches engram cells from an accessible state (where they can be reactivated by natural recall cues) to an inaccessible state (where they cannot). In many cases, forgetting rates are modulated by environmental conditions and we therefore propose that forgetting is a form of neuroplasticity that alters engram cell accessibility in a manner that is sensitive to mismatches between expectations and the environment. Moreover, we hypothesize that disease states associated with forgetting may hijack natural forgetting mechanisms, resulting in reduced engram cell accessibility and memory loss.
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Affiliation(s)
- Tomás J Ryan
- School of Biochemistry and Immunology, Trinity College Dublin, Dublin, Ireland. .,Trinity College Institute for Neuroscience, Trinity College Dublin, Dublin, Ireland. .,Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Melbourne, Victoria, Australia. .,Child & Brain Development Program, Canadian Institute for Advanced Research (CIFAR), Toronto, Ontario, Canada.
| | - Paul W Frankland
- Child & Brain Development Program, Canadian Institute for Advanced Research (CIFAR), Toronto, Ontario, Canada. .,Program in Neurosciences & Mental Health, Hospital for Sick Children, Toronto, Ontario, Canada. .,Department of Psychology, University of Toronto, Toronto, Ontario, Canada. .,Department of Physiology, University of Toronto, Toronto, Ontario, Canada. .,Institute of Medical Sciences, University of Toronto, Toronto, Ontario, Canada.
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14
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Montalbano G, Bertolucci C, Lucon-Xiccato T. Cognitive Phenotypic Plasticity: Environmental Enrichment Affects Learning but Not Executive Functions in a Teleost Fish, Poecilia reticulata. BIOLOGY 2022; 11:64. [PMID: 35053062 PMCID: PMC8772815 DOI: 10.3390/biology11010064] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/11/2021] [Revised: 12/21/2021] [Accepted: 12/30/2021] [Indexed: 11/16/2022]
Abstract
Many aspects of animal cognition are plastically adjusted in response to the environment through individual experience. A remarkable example of this cognitive phenotypic plasticity is often observed when comparing individuals raised in a barren environment to individuals raised in an enriched environment. Evidence of enrichment-driven cognitive plasticity in teleost fish continues to grow, but it remains restricted to a few cognitive traits. The purpose of this study was to investigate how environmental enrichment affects multiple cognitive traits (learning, cognitive flexibility, and inhibitory control) in the guppy, Poecilia reticulata. To reach this goal, we exposed new-born guppies to different treatments: an enrichment environment with social companions, natural substrate, vegetation, and live prey or a barren environment with none of the above. After a month of treatment, we tested the subjects in a battery of three cognitive tasks. Guppies from the enriched environment learned a color discrimination faster compared to guppies from the environment with no enrichments. We observed no difference between guppies of the two treatments in the cognitive flexibility task, requiring selection of a previously unrewarded stimulus, nor in the inhibitory control task, requiring the inhibition of the attack response toward live prey. Overall, the results indicated that environmental enrichment had an influence on guppies' learning ability, but not on the remaining cognitive functions investigated.
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Affiliation(s)
- Giulia Montalbano
- Department of Life Sciences and Biotechnology, University of Ferrara, 44121 Ferrara, Italy;
| | - Cristiano Bertolucci
- Department of Life Sciences and Biotechnology, University of Ferrara, 44121 Ferrara, Italy;
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15
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Shepherd A, Zhang T, Hoffmann LB, Zeleznikow-Johnston AM, Churilov L, Hannan AJ, Burrows EL. A Preclinical Model of Computerized Cognitive Training: Touchscreen Cognitive Testing Enhances Cognition and Hippocampal Cellular Plasticity in Wildtype and Alzheimer's Disease Mice. Front Behav Neurosci 2021; 15:766745. [PMID: 34938165 PMCID: PMC8685297 DOI: 10.3389/fnbeh.2021.766745] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Accepted: 11/12/2021] [Indexed: 11/29/2022] Open
Abstract
With the growing popularity of touchscreen cognitive testing in rodents, it is imperative to understand the fundamental effects exposure to this paradigm can have on the animals involved. In this study, we set out to assess hippocampal-dependant learning in the APP/PS1 mouse model of Alzheimer’s disease (AD) on two highly translatable touchscreen tasks – the Paired Associate Learning (PAL) task and the Trial Unique Non-Matching to Location (TUNL) task. Both of these tests are based on human tasks from the Cambridge Neuropsychological Test Automated Battery (CANTAB) and are sensitive to deficits in both mild cognitive impairment (MCI) and AD. Mice were assessed for deficits in PAL at 9–12 months of age, then on TUNL at 8–11 and 13–16 months. No cognitive deficits were evident in APP/PS1 mice at any age, contrary to previous reports using maze-based learning and memory tasks. We hypothesized that daily and long-term touchscreen training may have inadvertently acted as a cognitive enhancer. When touchscreen-tested mice were assessed on the Morris water maze, they showed improved task acquisition compared to naïve APP/PS1 mice and wild-type (WT) littermate controls. In addition, we show that touchscreen-trained WT and APP/PS1 mice show increased cell proliferation and immature neuron numbers in the dentate gyrus compared to behaviorally naïve WT and APP/PS1 mice. This result indicates that the touchscreen testing paradigm could improve cognitive performance, and/or mask an impairment, in experimental mouse models. This touchscreen-induced cognitive enhancement may involve increased neurogenesis, and possibly other forms of cellular plasticity. This is the first study to show increased numbers of proliferating cells and immature neurons in the hippocampus following touchscreen testing, and that touchscreen training can improve cognitive performance in maze-based spatial navigation tasks. This potential for touchscreen testing to induce cognitive enhancement, or other phenotypic shifts, in preclinical models should be considered in study design. Furthermore, touchscreen-mediated cognitive enhancement could have therapeutic implications for cognitive disorders.
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Affiliation(s)
- Amy Shepherd
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Parkville, VIC, Australia
| | - Tracy Zhang
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Parkville, VIC, Australia
| | - Lucas B Hoffmann
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Parkville, VIC, Australia
| | - Ariel M Zeleznikow-Johnston
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Parkville, VIC, Australia
| | - Leonid Churilov
- Melbourne Medical School, The University of Melbourne, Parkville, VIC, Australia
| | - Anthony J Hannan
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Parkville, VIC, Australia.,Department of Anatomy and Neuroscience, The University of Melbourne, Parkville, VIC, Australia
| | - Emma L Burrows
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Parkville, VIC, Australia
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16
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Barker SJ, Raju RM, Milman NEP, Wang J, Davila-Velderrain J, Gunter-Rahman F, Parro CC, Bozzelli PL, Abdurrob F, Abdelaal K, Bennett DA, Kellis M, Tsai LH. MEF2 is a key regulator of cognitive potential and confers resilience to neurodegeneration. Sci Transl Med 2021; 13:eabd7695. [PMID: 34731014 PMCID: PMC9258338 DOI: 10.1126/scitranslmed.abd7695] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
[Figure: see text].
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Affiliation(s)
- Scarlett J Barker
- Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.,Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Ravikiran M Raju
- Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.,Division of Newborn Medicine, Boston Children's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Noah E P Milman
- Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Jun Wang
- Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Jose Davila-Velderrain
- Computer Science and Artificial Intelligence Laboratory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Fatima Gunter-Rahman
- Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Cameron C Parro
- Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - P Lorenzo Bozzelli
- Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Fatema Abdurrob
- Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Karim Abdelaal
- Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - David A Bennett
- Rush Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL 60612, USA
| | - Manolis Kellis
- Computer Science and Artificial Intelligence Laboratory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.,Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Li-Huei Tsai
- Picower Institute for Learning and Memory, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.,Department of Brain and Cognitive Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.,Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
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17
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Effects of chronic tramadol administration on cognitive flexibility in mice. Psychopharmacology (Berl) 2021; 238:2883-2893. [PMID: 34173033 DOI: 10.1007/s00213-021-05903-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Accepted: 06/08/2021] [Indexed: 10/21/2022]
Abstract
RATIONALE Tramadol is widely used for pain relief especially in seniors. However, long-term use of tramadol has serious adverse effects, including cognitive impairment. Besides its memory effects, already demonstrated in animals, a recent clinical report suggests that tramadol could also affect executive function in seniors. Several studies have hypothesized that the anti-muscarinic properties of tramadol could be responsible for the deleterious effects of tramadol on cognition. OBJECTIVES We aimed at investigating the effects of chronic administration of tramadol on cognitive flexibility in adult male mice, as assessed by a visual discrimination reversal task using a touchscreen device. The effects of tramadol were further compared to those of scopolamine, a reference muscarinic antagonist. RESULTS We found that, during the early phase of the reversal task, when cognitive flexibility is most in demand, both tramadol-treated mice (20 mg/kg, s.c., twice a day) and scopolamine-treated mice (0.5 mg/kg, s.c., twice a day) needed more correction trials and showed a higher perseveration index than saline-treated mice. Therefore, tramadol affects cognitive flexibility, and its anticholinergic properties could be at least partly involved in these deficits. CONCLUSIONS In view of these deleterious cognitive effects of tramadol, physicians should be cautious when prescribing this analgesic, especially in seniors who are more vulnerable to adverse drug events and in which alternative prescription should be preferred whenever possible.
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18
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Barnard IL, Onofrychuk TJ, McElroy DL, Howland JG. The Touchscreen-Based Trial-Unique, Nonmatching-To-Location (TUNL) Task as a Measure of Working Memory and Pattern Separation in Rats and Mice. Curr Protoc 2021; 1:e238. [PMID: 34570962 DOI: 10.1002/cpz1.238] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The TUNL task is an automated touchscreen task used to evaluate the cognitive processes involved in working memory (WM) and spatial pattern separation in rodents. Both rats and mice can be used. To elicit working memory processes, the rodent must distinguish between a sample (familiar) light stimulus and a novel light stimulus after a delay. With a correct selection, the rodent will receive a food reward. A major benefit of TUNL compared to other similar tasks is the circumvention of spatial "mediating strategies" that the rodent may use to supplement or replace working memory processes to complete the task successfully. Each trial is 'unique', as the stimuli are pseudo-randomized between trials in an array of spatial locations. The TUNL task uses a progression of six training steps to teach the rodent the associated rules necessary to complete the full task. Task performance is typically measured by trials completed and by accuracy. Task accuracy can be evaluated across various spatial separations to engage hippocampal-dependent processes involved in spatial pattern separation. The latency between trial responses can also be evaluated, with food reward collection latency as a measure of motivation. The TUNL task can be used to assess working memory and cognitive deficits in rodent models with neurodegenerative and neurological disorders, providing a valuable tool to screen for new treatment options, in addition to assessing basic neurobiology. © 2021 Wiley Periodicals LLC. Basic Protocol 1: Handling and habituation prior to training Basic Protocol 2: Initial Touch Training Basic Protocol 3: Must Touch Training Basic Protocol 4: Must Initiate Training Basic Protocol 5: Punish Incorrect Training Basic Protocol 6: Initial TUNL Training Basic Protocol 7: Full TUNL Training Support Protocol 1: Using ABET II touch program Support Protocol 2: Preparation of touchscreen chambers prior to training sessions.
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Affiliation(s)
- Ilne L Barnard
- Department of Anatomy, Physiology, and Pharmacology, University of Saskatchewan, Saskatoon, Canada
| | - Timothy J Onofrychuk
- Department of Anatomy, Physiology, and Pharmacology, University of Saskatchewan, Saskatoon, Canada
| | - Dan L McElroy
- Department of Anatomy, Physiology, and Pharmacology, University of Saskatchewan, Saskatoon, Canada
| | - John G Howland
- Department of Anatomy, Physiology, and Pharmacology, University of Saskatchewan, Saskatoon, Canada
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19
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Progressive impairments in executive function in the APP/PS1 model of Alzheimer's disease as measured by translatable touchscreen testing. Neurobiol Aging 2021; 108:58-71. [PMID: 34509856 DOI: 10.1016/j.neurobiolaging.2021.08.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2019] [Revised: 07/19/2021] [Accepted: 08/04/2021] [Indexed: 02/08/2023]
Abstract
Executive function deficits in Alzheimer's disease (AD) occur early in disease progression and may be predictive of cognitive decline. However, no preclinical studies have identified deficits in rewarded executive function in the commonly used APPSwe/PS1∆E9 (APP/PS1) mouse model. To address this, we assessed 12-26 month old APP/PS1 mice on rewarded reversal and/or extinction tasks. 16-month-old, but not 13- or 26-month-old, APP/PS1 mice showed an attenuated rate of extinction. Reversal deficits were seen in 22-month-old, but not 13-month-old APP/PS1 animals. We then confirmed that impairments in reversal were unrelated to previously reported visual impairments in both AD mouse models and humans. Age, but not genotype, had a significant effect on markers of retinal health, indicating the deficits seen in APP/PS1 mice were directly related to cognition. This is the first characterisation of rewarded executive function in APP/PS1 mice, and has great potential to facilitate translation from preclinical models to the clinic.
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20
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Santacà M, Dadda M, Miletto Petrazzini ME, Bisazza A. Stimulus characteristics, learning bias and visual discrimination in zebrafish (Danio rerio). Behav Processes 2021; 192:104499. [PMID: 34499984 DOI: 10.1016/j.beproc.2021.104499] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Revised: 07/31/2021] [Accepted: 09/03/2021] [Indexed: 12/27/2022]
Abstract
Zebrafish is an emerging model in the study of brain function; however, knowledge about its behaviour and cognition is incomplete. Previous studies suggest this species has limited ability in visual learning tasks compared to other teleosts. In this study, we systematically examined zebrafish's ability to learn to discriminate colour, shape, size, and orientation of figures using an appetitive conditioning paradigm. Contrary to earlier reports, the zebrafish successfully completed all tasks. Not all discriminations were learned with the same speed and accuracy. Subjects discriminated the size of objects better than their shape or colour. In all three tasks, they were faster and more accurate when required to discriminate between outlined figures than between filled figures. With stimuli consisting of outlines, the learning performance of zebrafish was comparable to that observed in higher vertebrates. Zebrafish easily learned a horizontal-vertical discrimination task, but like many other vertebrates, they had great difficulty discriminating a figure from its mirror image. Performance was more accurate for subjects reinforced on one stimulus (green over red, triangle over circle, large over small). Unexpectedly, these stimulus biases occurred only when zebrafish were tested with filled figures, suggesting some causal relationship between stimulus preference, learning bias and performance.
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Affiliation(s)
- Maria Santacà
- Department of General Psychology, University of Padova, Padova, Italy.
| | - Marco Dadda
- Department of General Psychology, University of Padova, Padova, Italy
| | | | - Angelo Bisazza
- Department of General Psychology, University of Padova, Padova, Italy; Padua Neuroscience Center, University of Padova, Padova, Italy
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21
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Lambert CT, Guillette LM. The impact of environmental and social factors on learning abilities: a meta-analysis. Biol Rev Camb Philos Soc 2021; 96:2871-2889. [PMID: 34342125 DOI: 10.1111/brv.12783] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Revised: 07/12/2021] [Accepted: 07/16/2021] [Indexed: 12/20/2022]
Abstract
Since the 1950s, researchers have examined how differences in the social and asocial environment affect learning in rats, mice, and, more recently, a variety of other species. Despite this large body of research, little has been done to synthesize these findings and to examine if social and asocial environmental factors have consistent effects on cognitive abilities, and if so, what aspects of these factors have greater or lesser impact. Here, we conducted a systematic review and meta-analysis examining how different external environmental features, including the social environment, impact learning (both speed of acquisition and performance). Using 531 mean-differences from 176 published articles across 27 species (with studies on rats and mice being most prominent) we conducted phylogenetically corrected mixed-effects models that reveal: (i) an average absolute effect size |d| = 0.55 and directional effect size d = 0.34; (ii) interventions manipulating the asocial environment result in larger effects than social interventions alone; and (iii) the length of the intervention is a significant predictor of effect size, with longer interventions resulting in larger effects. Additionally, much of the variation in effect size remained unexplained, possibly suggesting that species differ widely in how they are affected by environmental interventions due to varying ecological and evolutionary histories. Overall our results suggest that social and asocial environmental factors do significantly affect learning, but these effects are highly variable and perhaps not always as predicted. Most notably, the type (social or asocial) and length of interventions are important in determining the strength of the effect.
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Affiliation(s)
- Connor T Lambert
- Department of Psychology, University of Alberta, P217 Biological Sciences Building, Edmonton, AB, T6G 2R3, Canada
| | - Lauren M Guillette
- Department of Psychology, University of Alberta, P217 Biological Sciences Building, Edmonton, AB, T6G 2R3, Canada
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22
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Burrows EL, May C, Hill T, Churliov L, Johnson KA, Hannan AJ. Mice with an autism-associated R451C mutation in neuroligin-3 show a cautious but accurate response style in touchscreen attention tasks. GENES, BRAIN, AND BEHAVIOR 2021; 21:e12757. [PMID: 34085373 PMCID: PMC9744539 DOI: 10.1111/gbb.12757] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Revised: 05/30/2021] [Accepted: 06/02/2021] [Indexed: 11/30/2022]
Abstract
One of the earliest identifiable features of autism spectrum disorder (ASD) is altered attention. Mice expressing the ASD-associated R451C mutation in synaptic adhesion protein neuroligin-3 (NL3) exhibit impaired reciprocal social interactions and repetitive and restrictive behaviours. The role of this mutation in attentional abnormalities has not been established. We assessed attention in male NL3R451C mice using two well-established tasks in touchscreen chambers. In the 5-choice serial reaction task, rodents were trained to attend to light stimuli that appear in any one of five locations. While no differences between NL3R451C and WT mice were seen in accuracy or omissions, slower response times and quicker reward collection latencies were seen across all training and probe trials. In the rodent continuous-performance test, animals were required to discriminate, and identify a visual target pattern over multiple distractor stimuli. NL3R451C mice displayed enhanced ability to attend to stimuli when task-load was low during training and baseline but lost this advantage when difficulty was increased by altering task parameters in probe trials. NL3R451C mice made less responses to the distractor stimuli, exhibiting lower false alarm rates during all training stages and in probe trials. Slower response times and quicker reward latencies were consistently seen in NL3R451C mice in the rCPT. Slower response times are a major cognitive phenotype reported in ASD patients and are indicative of slower processing speed. Enhanced attention has been shown in a subset of ASD patients and we have demonstrated this phenotype also exists in the NL3R451C mouse model.
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Affiliation(s)
- Emma L. Burrows
- Florey Institute of Neuroscience and Mental Health, University of MelbourneParkvilleVictoriaAustralia
| | - Carlos May
- Florey Institute of Neuroscience and Mental Health, University of MelbourneParkvilleVictoriaAustralia
| | - Thomas Hill
- Florey Institute of Neuroscience and Mental Health, University of MelbourneParkvilleVictoriaAustralia
| | - Leonid Churliov
- Florey Institute of Neuroscience and Mental HealthHeidelbergVictoriaAustralia
| | - Katherine A. Johnson
- School of Psychological SciencesUniversity of MelbourneParkvilleVictoriaAustralia
| | - Anthony J. Hannan
- Florey Institute of Neuroscience and Mental Health, University of MelbourneParkvilleVictoriaAustralia,Department of Anatomy and NeuroscienceUniversity of MelbourneParkvilleVictoriaAustralia
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23
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Zhao X, Mohammed R, Tran H, Erickson M, Kentner AC. Poly (I:C)-induced maternal immune activation modifies ventral hippocampal regulation of stress reactivity: prevention by environmental enrichment. Brain Behav Immun 2021; 95:203-215. [PMID: 33766701 PMCID: PMC8187276 DOI: 10.1016/j.bbi.2021.03.018] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/14/2021] [Revised: 02/28/2021] [Accepted: 03/17/2021] [Indexed: 12/14/2022] Open
Abstract
Environmental enrichment (EE) has been successfully implemented in human rehabilitation settings. However, the mechanisms underlying its success are not understood. Incorporating components of EE protocols into our animal models allows for the exploration of these mechanisms and their role in mitigation. Using a mouse model of maternal immune activation (MIA), the present study explored disruptions in social behavior and associated hypothalamic pituitary adrenal (HPA) axis functioning, and whether a supportive environment could prevent these effects. We show that prenatal immune activation of toll-like receptor 3, by the viral mimetic polyinosinic-polycytidylic acid (poly(I:C)), led to disrupted maternal care in that dams built poorer quality nests, an effect corrected by EE housing. Standard housed male and female MIA mice engaged in higher rates of repetitive rearing and had lower levels of social interaction, alongside sex-specific expression of several ventral hippocampal neural stress markers. Moreover, MIA males had delayed recovery of plasma corticosterone in response to a novel social encounter. Enrichment housing, likely mediated by improved maternal care, protected against these MIA-induced effects. We also evaluated c-Fos immunoreactivity associated with the novel social experience and found MIA to decrease neural activation in the dentate gyrus. Activation in the hypothalamus was blunted in EE housed animals, suggesting that the putative circuits modulating social behaviors may be different between standard and complex housing environments. These data demonstrate that augmentation of the environment supports parental care and offspring safety/security, which can offset effects of early health adversity by buffering HPA axis dysregulation. Our findings provide further evidence for the viability of EE interventions in maternal and pediatric settings.
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Affiliation(s)
| | | | | | | | - Amanda C. Kentner
- Corresponding author: Amanda Kentner, , Office #617-274-3360, Fax # 617-732-2959
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24
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Li S, May C, Hannan AJ, Johnson KA, Burrows EL. Assessing attention orienting in mice: a novel touchscreen adaptation of the Posner-style cueing task. Neuropsychopharmacology 2021; 46:432-441. [PMID: 33007776 PMCID: PMC7853131 DOI: 10.1038/s41386-020-00873-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/02/2020] [Accepted: 09/21/2020] [Indexed: 01/10/2023]
Abstract
Atypical attention orienting has been found to be impaired in many neuropsychological disorders, but the underlying neural mechanism remains unclear. Attention can be oriented exogenously (i.e., driven by salient stimuli) or endogenously (i.e., driven by one's goals or intentions). Genetic mouse models are useful tools to investigate the neurobiology of cognition, but a well-established assessment of attention orienting in mice is missing. This study aimed to adapt the Posner task, a widely used attention orienting task in humans, for use in mice using touchscreen technology and to test the effects of two attention-modulating drugs, methylphenidate (MPH) and atomoxetine (ATX), on the performance of mice during this task. In accordance with human performance, mice responded more quickly and more accurately to validly cued targets compared to invalidly cued targets, thus supporting mice as a valid animal model to study the neural mechanisms of attention orienting. This is the first evidence that mice can be trained to voluntarily maintain their nose-poke on a touchscreen and to complete attention orienting tasks using exogenous peripheral cues and endogenous symbolic cues. The results also showed no significant effects of MPH and ATX on attention orienting, although MPH improved overall response times in mice during the exogenous orienting task. In summary, the current study provides a critical translational task for assessing attention orienting in mice and to investigate the effects of attention-modulating drugs on attention orienting.
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Affiliation(s)
- S. Li
- grid.1008.90000 0001 2179 088XMelbourne School of Psychological Sciences, University of Melbourne, Parkville, VIC 3010 Australia
| | - C. May
- grid.1008.90000 0001 2179 088XFlorey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Parkville, VIC 3010 Australia
| | - A. J. Hannan
- grid.1008.90000 0001 2179 088XFlorey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Parkville, VIC 3010 Australia ,grid.1008.90000 0001 2179 088XDepartment of Anatomy and Neuroscience, University of Melbourne, Parkville, VIC 3010 Australia
| | - K. A. Johnson
- grid.1008.90000 0001 2179 088XMelbourne School of Psychological Sciences, University of Melbourne, Parkville, VIC 3010 Australia
| | - E. L. Burrows
- grid.1008.90000 0001 2179 088XFlorey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Parkville, VIC 3010 Australia
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25
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Fulopova B, Stuart KE, Bennett W, Bindoff A, King AE, Vickers JC, Canty AJ. Regional differences in beta amyloid plaque deposition and variable response to midlife environmental enrichment in the cortex of APP/PS1 mice. J Comp Neurol 2020; 529:1849-1862. [PMID: 33104234 DOI: 10.1002/cne.25060] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Revised: 10/20/2020] [Accepted: 10/21/2020] [Indexed: 01/21/2023]
Abstract
Environmentally enriched housing conditions can increase performance on cognitive tasks in APP/PS1 mice; however, the potential effects of environmental enrichment (EE) on disease modification in terms of pathological change are inconclusive. We hypothesized that previous contrasting findings may be attributable to regional differences in susceptibility to amyloid beta (Aβ) plaque deposition in cortical regions that are functionally associated with EE. We characterized fibrillar plaque deposition in 6, 12, and 18-22 months old APP/PS1 mice in the prefrontal (PFC), somatosensory (SS2), and primary motor cortex (M1). We found a significant increase in plaque load between 6 and 12 months in all regions. In animals over 12 months, only the PFC region continued to significantly accumulate plaques. Additionally, 12 months old animals subjected to 6 months of EE showed improved spatial navigation and had significantly fewer plaques in M1 and SS2, but not in the PFC. These findings suggest that the PFC region is selectively susceptible to Aβ deposition and less responsive to the attenuating effects of EE. In contrast, M1 and SS2 regions plateau with respect to Aβ deposition by 12 months of age and are susceptible to amyloid pathology modification by midlife EE.
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Affiliation(s)
- Barbora Fulopova
- Wicking Dementia Research and Education Centre, University of Tasmania, Hobart, Tasmania, Australia
| | - Kimberley E Stuart
- Wicking Dementia Research and Education Centre, University of Tasmania, Hobart, Tasmania, Australia
| | - William Bennett
- Wicking Dementia Research and Education Centre, University of Tasmania, Hobart, Tasmania, Australia
| | - Aidan Bindoff
- Wicking Dementia Research and Education Centre, University of Tasmania, Hobart, Tasmania, Australia
| | - Anna E King
- Wicking Dementia Research and Education Centre, University of Tasmania, Hobart, Tasmania, Australia
| | - James C Vickers
- Wicking Dementia Research and Education Centre, University of Tasmania, Hobart, Tasmania, Australia
| | - Alison J Canty
- Wicking Dementia Research and Education Centre, University of Tasmania, Hobart, Tasmania, Australia
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Smail MA, Smith BL, Nawreen N, Herman JP. Differential impact of stress and environmental enrichment on corticolimbic circuits. Pharmacol Biochem Behav 2020; 197:172993. [PMID: 32659243 DOI: 10.1016/j.pbb.2020.172993] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/09/2020] [Revised: 05/27/2020] [Accepted: 07/02/2020] [Indexed: 12/12/2022]
Abstract
Stress exposure can produce profound changes in physiology and behavior that can impair health and well-being. Of note, stress exposure is linked to anxiety disorders and depression in humans. The widespread impact of these disorders warrants investigation into treatments to mitigate the harmful effects of stress. Pharmacological treatments fail to help many with these disorders, so recent work has focused on non-pharmacological alternatives. One of the most promising of these alternatives is environmental enrichment (EE). In rodents, EE includes social, physical, and cognitive stimulation for the animal, in the form of larger cages, running wheels, and toys. EE successfully reduces the maladaptive effects of various stressors, both as treatment and prophylaxis. While we know that EE can have beneficial effects under stress conditions, the morphological and molecular mechanisms underlying these behavioral effects are still not well understood. EE is known to alter neurogenesis, dendrite development, and expression of neurotrophic growth factors, effects that vary by type of enrichment, age, and sex. To add to this complexity, EE has differential effects in different brain regions. Understanding how EE exerts its protective effects on morphological and molecular levels could hold the key to developing more targeted pharmacological treatments. In this review, we summarize the literature on the morphological and molecular consequences of EE and stress in key emotional regulatory pathways in the brain, the hippocampus, prefrontal cortex, and amygdala. The similarities and differences among these regions provide some insight into stress-EE interaction that may be exploited in future efforts toward prevention of, and intervention in, stress-related diseases.
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Affiliation(s)
- Marissa A Smail
- Department of Pharmacology and Systems Physiology, University of Cincinnati, Cincinnati, OH, United States; Neuroscience Graduate Program, University of Cincinnati, Cincinnati, OH, United States.
| | - Brittany L Smith
- Department of Pharmacology and Systems Physiology, University of Cincinnati, Cincinnati, OH, United States
| | - Nawshaba Nawreen
- Department of Pharmacology and Systems Physiology, University of Cincinnati, Cincinnati, OH, United States; Neuroscience Graduate Program, University of Cincinnati, Cincinnati, OH, United States
| | - James P Herman
- Department of Pharmacology and Systems Physiology, University of Cincinnati, Cincinnati, OH, United States; Veterans Affairs Medical Center, Cincinnati, OH, United States; Department of Neurology, University of Cincinnati, Cincinnati, OH, United States
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Therapeutic efficacy of environmental enrichment for substance use disorders. Pharmacol Biochem Behav 2019; 188:172829. [PMID: 31778722 DOI: 10.1016/j.pbb.2019.172829] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Revised: 11/13/2019] [Accepted: 11/15/2019] [Indexed: 12/18/2022]
Abstract
Addiction to drug and alcohol is regarded as a major health problem worldwide for which available treatments show limited effectiveness. The biggest challenge remains to enhance the capacities of interventions to reduce craving, prevent relapse and promote long-term recovery. New strategies to meet these challenges are being explored. Findings from preclinical work suggest that environmental enrichment (EE) holds therapeutic potential for the treatment of substance use disorders, as demonstrated in a number of animal models of drug abuse. The EE intervention introduced after drug exposure leads to attenuation of compulsive drug taking, attenuation of the rewarding (and reinforcing) effects of drugs, reductions in control of behavior by drug cues, and, very importantly, relapse prevention. Clinical work also suggests that multidimensional EE interventions (involving physical activity, social interaction, vocational training, recreational and community involvement) might produce similar therapeutic effects, if implemented continuously and rigorously. In this review we survey preclinical and clinical studies assessing the efficacy of EE as a behavioral intervention for substance use disorders and address related challenges. We also review work providing empirical evidence for EE-induced neuroplasticity within the mesocorticolimbic system that is believed to contribute to the seemingly therapeutic effects of EE on drug and alcohol-related behaviors.
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28
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Sampedro-Piquero P, Ladrón de Guevara-Miranda D, Pavón FJ, Serrano A, Suárez J, Rodríguez de Fonseca F, Santín LJ, Castilla-Ortega E. Neuroplastic and cognitive impairment in substance use disorders: a therapeutic potential of cognitive stimulation. Neurosci Biobehav Rev 2019; 106:23-48. [DOI: 10.1016/j.neubiorev.2018.11.015] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2018] [Revised: 10/15/2018] [Accepted: 11/23/2018] [Indexed: 01/08/2023]
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29
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Gubert C, Hannan AJ. Environmental enrichment as an experience-dependent modulator of social plasticity and cognition. Brain Res 2019; 1717:1-14. [DOI: 10.1016/j.brainres.2019.03.033] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Revised: 03/11/2019] [Accepted: 03/27/2019] [Indexed: 12/14/2022]
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30
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Rogers J, Chen F, Stanic D, Farzana F, Li S, Zeleznikow-Johnston AM, Nithianantharajah J, Churilov L, Adlard PA, Lanfumey L, Hannan AJ, Renoir T. Paradoxical effects of exercise on hippocampal plasticity and cognition in mice with a heterozygous null mutation in the serotonin transporter gene. Br J Pharmacol 2019; 176:3279-3296. [PMID: 31167040 DOI: 10.1111/bph.14760] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Revised: 05/08/2019] [Accepted: 05/14/2019] [Indexed: 12/30/2022] Open
Abstract
BACKGROUND AND PURPOSE Exercise is known to improve cognitive function, but the exact synaptic and cellular mechanisms remain unclear. We investigated the potential role of the serotonin (5-HT) transporter (SERT) in mediating these effects. EXPERIMENTAL APPROACH Hippocampal long-term potentiation (LTP) and neurogenesis were measured in standard-housed and exercising (wheel running) wild-type (WT) and SERT heterozygous (HET) mice. We also assessed hippocampal-dependent cognition using the Morris water maze (MWM) and a spatial pattern separation touchscreen task. KEY RESULTS SERT HET mice had impaired hippocampal LTP regardless of the housing conditions. Exercise increased hippocampal neurogenesis in WT mice. However, this was not observed in SERT HET animals, even though both genotypes used the running wheels to a similar extent. We also found that standard-housed SERT HET mice displayed altered cognitive flexibility than WT littermate controls in the MWM reversal learning task. However, SERT HET mice no longer exhibited this phenotype after exercise. Cognitive changes, specific to SERT HET mice in the exercise condition, were also revealed on the touchscreen spatial pattern separation task, especially when the cognitive pattern separation load was at its highest. CONCLUSIONS AND IMPLICATIONS Our study is the first evidence of reduced hippocampal LTP in SERT HET mice. We also show that functional SERT is required for exercise-induced increase in adult neurogenesis. Paradoxically, exercise had a negative impact on hippocampal-dependent cognitive tasks, especially in SERT HET mice. Taken together, our results suggest unique complex interactions between exercise and altered 5-HT homeostasis.
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Affiliation(s)
- Jake Rogers
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Melbourne, VIC, Australia
| | - Feng Chen
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Melbourne, VIC, Australia
| | - Davor Stanic
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Melbourne, VIC, Australia
| | - Farheen Farzana
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Melbourne, VIC, Australia
| | - Shanshan Li
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Melbourne, VIC, Australia
| | - Ariel M Zeleznikow-Johnston
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Melbourne, VIC, Australia
| | - Jess Nithianantharajah
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Melbourne, VIC, Australia
| | - Leonid Churilov
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Melbourne, VIC, Australia.,School of Mathematical and Geospatial Sciences, RMIT University, Melbourne, VIC, Australia
| | - Paul A Adlard
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Melbourne, VIC, Australia
| | - Laurence Lanfumey
- UMR S894, Université Paris Descartes, Paris, France.,Centre de Psychiatrie et Neurosciences, Inserm UMR 894, Paris, France
| | - Anthony J Hannan
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Melbourne, VIC, Australia.,Department of Anatomy and Neuroscience, University of Melbourne, Melbourne, VIC, Australia.,Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Melbourne, VIC, Australia
| | - Thibault Renoir
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Melbourne, VIC, Australia.,Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Melbourne, VIC, Australia
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31
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Gelfo F. Does Experience Enhance Cognitive Flexibility? An Overview of the Evidence Provided by the Environmental Enrichment Studies. Front Behav Neurosci 2019; 13:150. [PMID: 31338030 PMCID: PMC6629767 DOI: 10.3389/fnbeh.2019.00150] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Accepted: 06/21/2019] [Indexed: 12/16/2022] Open
Abstract
Neuroplasticity accounts for the ability of the brain to change in both structure and function in consequence of life experiences. An enhanced stimulation provided by the environment is able to create a form of brain, neural, and cognitive reserve, which allows an individual to cope better with the environmental demands, also in case of neural damage leading to cognitive decline. With its complex manipulation of several stimuli, the animal experimental paradigm of environmental enrichment (EE) appears particularly effective in modulating the ability to successfully respond to the ever-changing characteristics of the environment. According to this point, it could be very relevant to analyze the specific effects of EE on cognitive flexibility (CF). CF could be defined as the ability to effectively change behavior in response to the environmental condition changing. This review article is specifically aimed to summarize and focus on the available evidence in relation to the effects of EE on CF. To this aim, findings obtained in behavioral tasks specifically structured to investigate animal CF, such as reversal learning and attentional set-shifting tests (tasks based on the request of responding to a rewarding rule that changes, within one or multiple perceptual dimensions), are reviewed. Data provided on the structural and biochemical correlates of these findings are also enumerated. Studies realized in healthy animals and also in pathological models are considered. On the whole, the summarized evidence clearly supports the specific beneficial effects of EE on CF. However, further studies on this key topic are strictly required to gain a comprehensive and detailed framework on the mechanisms by which an enhanced stimulation could improve CF.
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Affiliation(s)
- Francesca Gelfo
- Department of Human Sciences, Guglielmo Marconi University, Rome, Italy.,Department of Clinical and Behavioural Neurology, IRCCS Fondazione Santa Lucia, Rome, Italy
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32
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Barros W, David M, Souza A, Silva M, Matos R. Can the effects of environmental enrichment modulate BDNF expression in hippocampal plasticity? A systematic review of animal studies. Synapse 2019; 73:e22103. [PMID: 31056812 DOI: 10.1002/syn.22103] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Revised: 04/28/2019] [Accepted: 04/29/2019] [Indexed: 12/11/2022]
Abstract
BACKGROUND AND AIM Environmental enrichment (EE) can be related to changes in the expression of brain-derived neurotrophic factor (BDNF) in the hippocampus of adult rodents. Exposure to EE may also induce neurogenesis in the dentate gyrus (DG). The aim of this systematic review was to analyze the current literature on the correlation between neurogenesis and BDNF expression in the hippocampal DG region resulting from exposure to EE, which is associated with changes in memory, in rodents. METHODS Bibliographic searches of the Medline/PubMed and ScienceDirect databases were carried out, and 334 studies were found. A predefined protocol was used and registered on PROSPERO, and 32 studies were included for qualitative synthesis. The PRISMA was used to report this systematic review. RESULTS Most of the included studies showed that there is little evidence in the literature demonstrating that memory changes resulting from EE are dependent on BDNF expression and that there is an induction of neurogenesis in the hippocampal DG. However, the observed increase in molecular expression levels and cell proliferation is dependent on the age, the timing and duration of exposure to EE. Regarding the methodological quality of the studies, the majority presented a risk of bias due to the high variability in the age of the animals. CONCLUSION There are few studies in the literature that correlate the molecular and cellular mechanisms involved in neurogenesis in the hippocampal DG with BDNF expression in this region in rodents exposed to EE; however, there are other factors that can modulate this neurogenesis.
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Affiliation(s)
- Waleska Barros
- Programa de Pós-Graduação em Neuropsiquiatria e Ciências do Comportamento, Universidade Federal de Pernambuco (UFPE), Recife, Brazil.,CITENC (Centro integrado de tecnologia em neurociência), Centro Integrado de Tecnologia e Pesquisa (CINTEP) - Centro Universitário Osman Lins (FACOL), Vitória de Santo Antão, Brazil
| | - Mirian David
- Programa de Pós-Graduação em Neuropsiquiatria e Ciências do Comportamento, Universidade Federal de Pernambuco (UFPE), Recife, Brazil
| | - Ana Souza
- Fisioterapia, Centro Universitário Osman Lins (FACOL), Vitória de Santo Antão, Brazil
| | - Mariluce Silva
- Fisioterapia, Centro Universitário Osman Lins (FACOL), Vitória de Santo Antão, Brazil
| | - Rhowena Matos
- Programa de Pós-Graduação em Neuropsiquiatria e Ciências do Comportamento, Universidade Federal de Pernambuco (UFPE), Recife, Brazil.,Núcleo de Educação Física e Ciências do Esporte, Universidade Federal de Pernambuco Centro Acadêmico de Vitória (CAV), Vitória de Santo Antão, Brazil
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33
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Stroke Induces a BDNF-Dependent Improvement in Cognitive Flexibility in Aged Mice. Neural Plast 2019; 2019:1460890. [PMID: 31191635 PMCID: PMC6525942 DOI: 10.1155/2019/1460890] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Revised: 03/10/2019] [Accepted: 04/04/2019] [Indexed: 11/17/2022] Open
Abstract
Stroke remains a leading cause of disability worldwide. Recently, we have established an animal model of stroke that results in delayed impairment in spatial memory, allowing us to better investigate cognitive deficits. Young and aged brains show different recovery profiles after stroke; therefore, we assessed aged-related differences in poststroke cognition. As neurotrophic support diminishes with age, we also investigated the involvement of brain-derived neurotrophic factor (BDNF) in these differences. Young (3-6 months old) and aged (16-21 months old) mice were trained in operant touchscreen chambers to complete a visual pairwise discrimination (VD) task. Stroke or sham surgery was induced using the photothrombotic model to induce a bilateral prefrontal cortex stroke. Five days poststroke, an additional cohort of aged stroke animals were treated with intracerebral hydrogels loaded with the BDNF decoy, TrkB-Fc. Following treatment, animals underwent the reversal and rereversal task to identify stroke-induced cognitive deficits at days 17 and 37 poststroke, respectively. Assessment of sham animals using Cox regression and log-rank analyses showed aged mice exhibit an increased impairment on VD reversal and rereversal learning compared to young controls. Stroke to young mice revealed no impairment on either task. In contrast, stroke to aged mice facilitated a significant improvement in reversal learning, which was dampened in the presence of the BDNF decoy, TrkB-Fc. In addition, aged stroke control animals required significantly less consecutive days and correction trials to master the reversal task, relative to aged shams, an effect dampened by TrkB-Fc. Our findings support age-related differences in recovery of cognitive function after stroke. Interestingly, aged stroke animals outperformed their sham counterparts, suggesting reopening of a critical window for recovery that is being mediated by BDNF.
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34
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Shepherd A, Zhang TD, Zeleznikow-Johnston AM, Hannan AJ, Burrows EL. Transgenic Mouse Models as Tools for Understanding How Increased Cognitive and Physical Stimulation Can Improve Cognition in Alzheimer's Disease. Brain Plast 2018; 4:127-150. [PMID: 30564551 PMCID: PMC6296266 DOI: 10.3233/bpl-180076] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Cognitive decline appears as a core feature of dementia, of which the most prevalent form, Alzheimer's disease (AD) affects more than 45 million people worldwide. There is no cure, and therapeutic options remain limited. A number of modifiable lifestyle factors have been identified that contribute to cognitive decline in dementia. Sedentary lifestyle has emerged as a major modifier and accordingly, boosting mental and physical activity may represent a method to prevent decline in dementia. Beneficial effects of increased physical activity on cognition have been reported in healthy adults, showing potential to harness exercise and cognitive stimulation as a therapy in dementia. 'Brain training' (cognitive stimulation) has also been investigated as an intervention protecting against cognitive decline with normal aging. Consequently, the utility of exercise regimes and/or cognitive stimulation to improve cognition in dementia in clinical populations has been a major area of study. However, these therapies are in their infancy and efficacy is unclear. Investigations utilising animal models, where dose and timing of treatment can be tightly controlled, have provided many mechanistic insights. Genetically engineered mouse models are powerful tools to investigate mechanisms underlying cognitive decline, and also how environmental manipulations can alter both cognitive outcomes and pathology. A myriad of effects following physical activity and housing in enriched environments have been reported in transgenic mice expressing Alzheimer's disease-associated mutations. In this review, we comprehensively evaluate all studies applying environmental enrichment and/or increased physical exercise to transgenic mouse models of Alzheimer's disease. It is unclear whether interventions must be applied before first onset of cognitive deficits to be effective. In order to determine the importance of timing of interventions, we specifically scrutinised studies exposing transgenic mice to exercise and environmental enrichment before and after first report of cognitive impairment. We discuss the strengths and weaknesses of these preclinical studies and suggest approaches for enhancing rigor and using mechanistic insights to inform future therapeutic interventions.
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Affiliation(s)
- Amy Shepherd
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Parkville, VIC, Australia
| | - Tracy D Zhang
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Parkville, VIC, Australia
| | - Ariel M Zeleznikow-Johnston
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Parkville, VIC, Australia
| | - Anthony J Hannan
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Parkville, VIC, Australia.,Department of Anatomy and Neuroscience, University of Melbourne, Parkville, VIC, Australia
| | - Emma L Burrows
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Parkville, VIC, Australia
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35
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Zeleznikow-Johnston AM, Renoir T, Churilov L, Li S, Burrows EL, Hannan AJ. Touchscreen testing reveals clinically relevant cognitive abnormalities in a mouse model of schizophrenia lacking metabotropic glutamate receptor 5. Sci Rep 2018; 8:16412. [PMID: 30401923 PMCID: PMC6219561 DOI: 10.1038/s41598-018-33929-3] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2018] [Accepted: 10/08/2018] [Indexed: 11/09/2022] Open
Abstract
Metabotropic glutamate receptor 5 (mGlu5) has been implicated in certain forms of synaptic plasticity and cognitive function. mGlu5 knockout (KO) mice and mGlu5 antagonists have been previously used to study the pathophysiology of schizophrenia as they have been shown respectively to display or induce endophenotypes relevant to schizophrenia. While schizophrenia presents with generalized cognitive impairments, the cognitive phenotype of mice lacking mGlu5 has so far only been explored using largely hippocampal-dependent spatial and contextual memory tasks. To address this, we used a touchscreen system to assess mGlu5 KO mice for pairwise visual discrimination, reversal learning, and extinction of an instrumental response requiring no discrimination. Furthermore, we tested the role of mGlu5 in working memory using the Trial-Unique Non-Matching to Location (TUNL) task utilizing pharmacological ablation. mGlu5 KO mice were impaired on discrimination learning, taking longer to reach criterion and requiring more correction learning trials. Performance on reversal learning was also impaired, with mGlu5 KO mice demonstrating a perseverative phenotype. The mGlu5 KO mice responded at a higher rate during extinction, consistent with this perseverative profile. In contrast, wildtype mice treated acutely with an mGlu5 antagonist (MTEP) showed no deficits in a touchscreen task assessing working memory. The present study demonstrates learning and memory deficits as well as an increased perseverative phenotype following constitutive loss of mGlu5 in this mouse model of schizophrenia. These findings will inform translational approaches using this preclinical model and the pursuit of mGlu5 as therapeutic target for schizophrenia and other brain disorders.
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Affiliation(s)
- Ariel M Zeleznikow-Johnston
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Parkville, Australia
| | - Thibault Renoir
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Parkville, Australia
| | - Leonid Churilov
- Florey Institute of Neuroscience and Mental Health, 245 Burgundy St, Heidelberg, Australia
| | - Shanshan Li
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Parkville, Australia
| | - Emma L Burrows
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Parkville, Australia
| | - Anthony J Hannan
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Parkville, Australia. .,Department of Anatomy and Neuroscience, University of Melbourne, Parkville, Australia.
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36
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Grech AM, Ratnayake U, Hannan AJ, van den Buuse M, Hill RA. Sex-Dependent Effects of Environmental Enrichment on Spatial Memory and Brain-Derived Neurotrophic Factor (BDNF) Signaling in a Developmental "Two-Hit" Mouse Model Combining BDNF Haploinsufficiency and Chronic Glucocorticoid Stimulation. Front Behav Neurosci 2018; 12:227. [PMID: 30356704 PMCID: PMC6189322 DOI: 10.3389/fnbeh.2018.00227] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Accepted: 09/11/2018] [Indexed: 01/02/2023] Open
Abstract
Neurodevelopmental disorders are thought to be caused by a combination of adverse genetic and environmental insults. The "two-hit" hypothesis suggests that an early first "hit" primes the developing brain to be vulnerable to a second "hit" during adolescence which triggers behavioral dysfunction. We have previously modeled this scenario in mice and found that the combined effect of a genetic hapolinsuffuciency in the brain-derived neurotrophic factor (BDNF) gene (1st hit) and chronic corticosterone (CORT) treatment during adolescence (2nd hit), caused spatial memory impairments in adulthood. Environmental enrichment (EE) protocols are designed to stimulate experience-dependent plasticity and have shown therapeutic actions. This study investigated whether EE can reverse these spatial memory impairments. Wild-type (WT) and BDNF heterozygous (HET) mice were treated with corticosterone (CORT) in their drinking water (50 mg/L) from weeks 6 to 8 and exposed to EE from 7 to 9 weeks. Enriched housing included open top cages with additional toys, tunnels, housing, and platforms. Y-maze novel preference testing, to assess short-term spatial memory, was performed at 10 weeks of age. At week 16 dorsal hippocampus tissue was obtained for Western blot analysis of expression levels of BDNF, the BDNF receptor TrkB, and NMDA receptor subunits, GluNR1, 2A and 2B. As in our previous studies, spatial memory was impaired in our two-hit (BDNF HET + CORT) mice. Simultaneous EE prevented these impairments. However, EE appeared to worsen spatial memory performance in WT mice, particularly those exposed to CORT. While BDNF levels were lower in BDNF HET mice as expected, there were no further effects of CORT or EE in males but a close to significant female CORT × EE × genotype interaction which qualitatively corresponded with Y-maze performance. However, EE caused both sex- and genotype-specific effects on phosphorylated TrkB residues and GluNR expression within the dorsal hippocampus, with GluNR2B levels in males changing in parallel with spatial memory performance. In conclusion, beneficial effects of EE on spatial memory emerge only following two developmental disruptions. The mechanisms by which EE exerts its effects are likely via regulation of multiple activity-dependent pathways, including TrkB and NMDA receptor signaling.
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Affiliation(s)
- Adrienne M. Grech
- Department of Psychiatry, School of Clinical Sciences, Monash Medical Centre, Monash University, Clayton, VIC, Australia
- The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC, Australia
| | - Udani Ratnayake
- The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC, Australia
| | - Anthony J. Hannan
- The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC, Australia
| | - Maarten van den Buuse
- School of Psychology and Public Health, La Trobe University, Melbourne, VIC, Australia
- Department of Pharmacology, University of Melbourne, Melbourne, VIC, Australia
- The College of Public Health, Medical and Veterinary Sciences, James Cook University, Townsville, QLD, Australia
| | - Rachel A. Hill
- Department of Psychiatry, School of Clinical Sciences, Monash Medical Centre, Monash University, Clayton, VIC, Australia
- The Florey Institute of Neuroscience and Mental Health, University of Melbourne, Parkville, VIC, Australia
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37
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Sampedro-Piquero P, Álvarez-Suárez P, Moreno-Fernández RD, García-Castro G, Cuesta M, Begega A. Environmental Enrichment Results in Both Brain Connectivity Efficiency and Selective Improvement in Different Behavioral Tasks. Neuroscience 2018; 388:374-383. [PMID: 30086366 DOI: 10.1016/j.neuroscience.2018.07.036] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2018] [Revised: 07/19/2018] [Accepted: 07/20/2018] [Indexed: 12/26/2022]
Abstract
Exposure to environmental enrichment (EE) has been a useful model for studying the effects of experience on brain plasticity, but to date, few is known about the impact of this condition on the brain functional networks that probably underlies the multiple behavioral improvements. Hence, we assessed the effect of an EE protocol in adult Wistar rats on the performance in several behavioral tasks testing different domains (Open field (OP): locomotor activity; Elevated-zero maze (EZM): anxiety-related behaviors; 5-choice serial reaction time task (5-CSRTT): attentional processes; 4-arm radial water maze (4-RAWM): spatial memory) in order to check its effectiveness in a wide range of functions. After this, we analyzed the functional brain connectivity underlying each experimental condition through cytochrome C oxidase (COx) histochemistry. Our EE protocol reduced both locomotor activity in the OP and anxiety-related behaviors in the EZM. On the other hand, enriched rats showed more accuracy in the 4-RAWM, whereas 5-CSRTT performance was not significantly ameliorated by EE condition. In relation to COx functional connectivity, we found that EE reduced the number of strong positive correlations both in basal and training conditions, suggesting a modulating effect on specific brain connections. Our results suggest that EE seems to have a selective effect on specific brain regions, such as prefrontal cortex and hippocampus, leading to a more efficient brain connectivity.
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Affiliation(s)
- P Sampedro-Piquero
- Departamento de Psicobiología y Metodología de las Ciencias del Comportamiento, Instituto de Investigación Biomédica de Málaga (IBIMA), Facultad de Psicología, Universidad de Málaga, Spain.
| | | | - R D Moreno-Fernández
- Departamento de Psicobiología y Metodología de las Ciencias del Comportamiento, Instituto de Investigación Biomédica de Málaga (IBIMA), Facultad de Psicología, Universidad de Málaga, Spain
| | - G García-Castro
- Instituto de Neurociencias del Principado de Asturias INEUROPA, Departamento de Psicología, Facultad de Psicología, Universidad de Oviedo, Spain
| | - M Cuesta
- Instituto de Neurociencias del Principado de Asturias INEUROPA, Departamento de Psicología, Facultad de Psicología, Universidad de Oviedo, Spain
| | - A Begega
- Instituto de Neurociencias del Principado de Asturias INEUROPA, Departamento de Psicología, Facultad de Psicología, Universidad de Oviedo, Spain
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McQuaid RJ, Dunn R, Jacobson-Pick S, Anisman H, Audet MC. Post-weaning Environmental Enrichment in Male CD-1 Mice: Impact on Social Behaviors, Corticosterone Levels and Prefrontal Cytokine Expression in Adulthood. Front Behav Neurosci 2018; 12:145. [PMID: 30065637 PMCID: PMC6056618 DOI: 10.3389/fnbeh.2018.00145] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2018] [Accepted: 06/26/2018] [Indexed: 12/16/2022] Open
Abstract
Environmental enrichment is typically associated with enhanced well-being, improved cognitive function and stress resilience. However, in some instances grouping adult male mice in enriched conditions promoted a stressful environment, which resulted in elevated endocrine, monoamine and inflammatory outcomes in response to subsequent stressor exposure. The current investigation examined whether raising male mice in an enriched environment (EE) would modulate social and anxiety-like behaviors in early adulthood and influence brain expression of pro-inflammatory cytokines and brain-derived neurotrophic factor (BDNF). Immediately after weaning (postnatal day [PD] 21), CD-1 male mice were housed with their siblings (3/cage) for 6 weeks in an EE or a standard (SE) environment. Body weights and aggressive interactions were monitored weekly. Social avoidance behaviors in the social interaction test and anxiety-like behaviors in the elevated-plus maze were examined in early adulthood. Ninety minutes following the behavioral tests, mice were sacrificed and a blood sample and the prefrontal cortex (PFC) were collected for the determination of plasma corticosterone levels as well as cytokine and BDNF mRNA expression. Mice raised in an EE exhibited more wounds and gained less weight than mice housed in a SE. Enriched mice also spent a greater amount of time in proximity of a social target in the social interaction test and made fewer transitions into the closed arms of the elevated-plus maze. Interestingly, the elevated plasma corticosterone and upregulated prefrontal interleukin (IL)-1β expression observed after the social interaction test among the SE mice were not apparent among those housed in an EE. Enrichment also increased prefrontal BDNF expression, especially among mice that experienced the social interaction test. These results suggest that although raising male mice in an EE may elicit aggressive interactions between sibling cage-mates (as indicated by a high number of wounds), this environment also enhances social behaviors and limits the corticosterone and cytokine impacts of mild social stressors encountered in early adulthood.
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Affiliation(s)
- Robyn Jane McQuaid
- Institute of Mental Health Research, Royal Ottawa Mental Health Centre, Ottawa, ON, Canada.,Department of Neuroscience, Carleton University, Ottawa, ON, Canada
| | - Roderick Dunn
- Department of Neuroscience, Carleton University, Ottawa, ON, Canada
| | | | - Hymie Anisman
- Institute of Mental Health Research, Royal Ottawa Mental Health Centre, Ottawa, ON, Canada.,Department of Neuroscience, Carleton University, Ottawa, ON, Canada
| | - Marie-Claude Audet
- Institute of Mental Health Research, Royal Ottawa Mental Health Centre, Ottawa, ON, Canada.,Department of Neuroscience, Carleton University, Ottawa, ON, Canada.,School of Nutrition Sciences, University of Ottawa, Ottawa, ON, Canada
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Tarasova AY, Perepelkina OV, Lil’p IG, Revishchin AV, Pavlova GV, Poletaeva II. Influence of “Enriched Environment” on Behavior and Neurogenesis in Mice Selected by Cognitive Trait. Bull Exp Biol Med 2018; 164:583-586. [DOI: 10.1007/s10517-018-4036-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Indexed: 01/03/2023]
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Rountree-Harrison D, Burton TJ, Leamey CA, Sawatari A. Environmental Enrichment Expedites Acquisition and Improves Flexibility on a Temporal Sequencing Task in Mice. Front Behav Neurosci 2018; 12:51. [PMID: 29599712 PMCID: PMC5862792 DOI: 10.3389/fnbeh.2018.00051] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2017] [Accepted: 02/28/2018] [Indexed: 01/09/2023] Open
Abstract
Environmental enrichment (EE) via increased opportunities for voluntary exercise, sensory stimulation and social interaction, can enhance the function of and behaviours regulated by cognitive circuits. Little is known, however, as to how this intervention affects performance on complex tasks that engage multiple, definable learning and memory systems. Accordingly, we utilised the Olfactory Temporal Order Discrimination (OTOD) task which requires animals to recall and report sequence information about a series of recently encountered olfactory stimuli. This approach allowed us to compare animals raised in either enriched or standard laboratory housing conditions on a number of measures, including the acquisition of a complex discrimination task, temporal sequence recall accuracy (i.e., the ability to accurately recall a sequences of events) and acuity (i.e., the ability to resolve past events that occurred in close temporal proximity), as well as cognitive flexibility tested in the style of a rule reversal and an Intra-Dimensional Shift (IDS). We found that enrichment accelerated the acquisition of the temporal order discrimination task, although neither accuracy nor acuity was affected at asymptotic performance levels. Further, while a subtle enhancement of overall performance was detected for both rule reversal and IDS versions of the task, accelerated performance recovery could only be attributed to the shift-like contingency change. These findings suggest that EE can affect specific elements of complex, multi-faceted cognitive processes.
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Affiliation(s)
- Darius Rountree-Harrison
- Discipline of Physiology, School of Medical Sciences and the Bosch Institute, University of Sydney, Sydney, NSW, Australia
| | - Thomas J Burton
- Discipline of Physiology, School of Medical Sciences and the Bosch Institute, University of Sydney, Sydney, NSW, Australia.,Animal Behavioural Facility, School of Medical Sciences and the Bosch Institute, University of Sydney, Sydney, NSW, Australia
| | - Catherine A Leamey
- Discipline of Physiology, School of Medical Sciences and the Bosch Institute, University of Sydney, Sydney, NSW, Australia
| | - Atomu Sawatari
- Discipline of Physiology, School of Medical Sciences and the Bosch Institute, University of Sydney, Sydney, NSW, Australia
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Sampedro-Piquero P, Álvarez-Suárez P, Begega A. Coping with Stress During Aging: The Importance of a Resilient Brain. Curr Neuropharmacol 2018; 16:284-296. [PMID: 28925881 PMCID: PMC5843980 DOI: 10.2174/1570159x15666170915141610] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Revised: 09/12/2017] [Accepted: 01/01/1970] [Indexed: 12/11/2022] Open
Abstract
BACKGROUND Resilience is the ability to achieve a positive outcome when we are in the face of adversity. It supposes an active resistance to adversity by coping mechanisms in which genetic, molecular, neural and environmental factors are involved. Resilience has been usually studied in early ages and few is known about it during aging. METHODS In this review, we will address the age-related changes in the brain mechanisms involved in regulating the stress response. Furthermore, using the EE paradigm, we analyse the resilient potential of this intervention and its neurobiological basis. In this case, we will focus on identifying the characteristics of a resilient brain (modifications in HPA structure and function, neurogenesis, specific neuron types, glia, neurotrophic factors, nitric oxide synthase or microRNAs, among others). RESULTS The evidence suggests that a healthy lifestyle has a crucial role to promote a resilient brain during aging. Along with the behavioral changes described, a better regulation of HPA axis, enhanced levels of postmitotic type-3 cells or changes in GABAergic neurotransmission are some of the brain mechanisms involved in resilience. CONCLUSION Future research should identify different biomarkers that increase the resistance to develop mood disorders and based on this knowledge, develop new potential therapeutic targets.
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Affiliation(s)
- P. Sampedro-Piquero
- Departamento de Psicobiología y Metodología de las CC, Facultad de Psicología, Instituto de Investigación Biomédica de Málaga (IBIMA), Universidad de Málaga, Spain
| | - P. Álvarez-Suárez
- Institute of Neuroscience of the Principality of Asturias (INEUROPA), Department of Psychology, University of Oviedo, Spain
| | - A. Begega
- Institute of Neuroscience of the Principality of Asturias (INEUROPA), Department of Psychology, University of Oviedo, Spain
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Rogers J, Renoir T, Hannan AJ. Gene-environment interactions informing therapeutic approaches to cognitive and affective disorders. Neuropharmacology 2017; 145:37-48. [PMID: 29277490 DOI: 10.1016/j.neuropharm.2017.12.038] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2017] [Revised: 12/17/2017] [Accepted: 12/20/2017] [Indexed: 02/06/2023]
Abstract
Gene-environment interactions drive experience-dependent changes in the brain that alter cognition, emotion and behaviour. Positive engagement with the environment, through novel experience and physical activity, can improve brain function, although the mechanisms mediating such experience-dependent plasticity remain to be fully elucidated. In this article, we discuss the therapeutic value of environmental stimuli, exercise and environmental enrichment (EE), for cognitive and affective disorders, with implications for the understanding and treatment of depression and anxiety disorders. We demonstrate that environmental manipulations are potential therapeutic strategies for improving outcomes in these psychiatric disorders, including beneficial impacts on cognition. We discuss how EE and exercise are therapeutic environmental interventions impacting both affective and cognitive function. Serotonergic (5-HTergic) signaling is strongly implicated in the manifestation of psychiatric disorders and regulates cognitive and emotional processing that can underpin them. Thus, we focus on evidence implicating the serotonergic system in mediating gene-environment interactions to EE and exercise. Finally, we discuss robust gene-environment interactions associated with EE and exercise interventions, and their impacts on specific brain areas, particularly the hippocampus. We focus on potential mediators of this experience-dependent plasticity, including adult neurogenesis and brain-derived neurotrophic factor (BDNF). Furthermore, we explore molecular and cellular mechanisms of experience-dependent plasticity that potentially underlie the restoration of affective and cognitive phenotypes, thus identifying novel therapeutic targets. This article is part of the Special Issue entitled "Neurobiology of Environmental Enrichment".
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Affiliation(s)
- Jake Rogers
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Parkville, Australia
| | - Thibault Renoir
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Parkville, Australia
| | - Anthony J Hannan
- Florey Institute of Neuroscience and Mental Health, Melbourne Brain Centre, University of Melbourne, Parkville, Australia; Department of Anatomy and Neuroscience, University of Melbourne, Parkville, Australia.
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Radabaugh HL, LaPorte MJ, Greene AM, Bondi CO, Lajud N, Kline AE. Refining environmental enrichment to advance rehabilitation based research after experimental traumatic brain injury. Exp Neurol 2017; 294:12-18. [PMID: 28457905 DOI: 10.1016/j.expneurol.2017.04.013] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2017] [Revised: 04/20/2017] [Accepted: 04/26/2017] [Indexed: 12/22/2022]
Abstract
The typical environmental enrichment (EE) paradigm, which consists of continuous exposure after experimental traumatic brain injury (TBI), promotes behavioral and histological benefits. However, rehabilitation is often abbreviated in the clinic and administered in multiple daily sessions. While recent studies have demonstrated that a once daily 6-hr bout of EE confers benefits comparable to continuous EE, breaking the therapy into two shorter sessions may increase novelty and ultimately enhance recovery. Hence, the aim of the study was to test the hypothesis that functional and histological outcomes will be significantly improved by daily preclinical neurorehabilitation consisting of two 3-hr periods of EE vs. a single 6-hr session. Anesthetized adult male rats received a controlled cortical impact of moderate-to-severe injury (2.8mm tissue deformation at 4m/s) or sham surgery and were then randomly assigned to groups receiving standard (STD) housing, a single 6-hr session of EE, or two 3-hr sessions of EE daily for 3weeks. Motor function (beam-balance/traversal) and acquisition of spatial learning/memory retention (Morris water maze) were assessed on post-operative days 1-5 and 14-19, respectively. Cortical lesion volume was quantified on day 21. Both EE conditions improved motor function and acquisition of spatial learning, and reduced cortical lesion volume relative to STD housing (p<0.05), but did not differ from one another in any endpoint (p>0.05). The findings replicate previous work showing that 6-hr of EE daily is sufficient to confer behavioral and histological benefits after TBI and extend the findings by demonstrating that the benefits are comparable regardless of how the 6-hrs of EE are accrued. The relevance of the finding is that it can be extrapolated to the clinic and may benefit patients who cannot endure a single extended period of neurorehabilitation.
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Affiliation(s)
- Hannah L Radabaugh
- Physical Medicine & Rehabilitation, University of Pittsburgh, Pittsburgh, PA 15213, United States; Safar Center for Resuscitation Research, University of Pittsburgh, Pittsburgh, PA 15213, United States
| | - Megan J LaPorte
- Physical Medicine & Rehabilitation, University of Pittsburgh, Pittsburgh, PA 15213, United States; Safar Center for Resuscitation Research, University of Pittsburgh, Pittsburgh, PA 15213, United States
| | - Anna M Greene
- Physical Medicine & Rehabilitation, University of Pittsburgh, Pittsburgh, PA 15213, United States; Safar Center for Resuscitation Research, University of Pittsburgh, Pittsburgh, PA 15213, United States
| | - Corina O Bondi
- Physical Medicine & Rehabilitation, University of Pittsburgh, Pittsburgh, PA 15213, United States; Safar Center for Resuscitation Research, University of Pittsburgh, Pittsburgh, PA 15213, United States; Neurobiology, University of Pittsburgh, Pittsburgh, PA 15213, United States; Center for Neuroscience, University of Pittsburgh, Pittsburgh, PA 15213, United States; Center for the Neural Basis of Cognition, University of Pittsburgh, Pittsburgh, PA 15213, United States
| | - Naima Lajud
- Physical Medicine & Rehabilitation, University of Pittsburgh, Pittsburgh, PA 15213, United States; Safar Center for Resuscitation Research, University of Pittsburgh, Pittsburgh, PA 15213, United States; División de Neurociencias, Centro de Investigación Biomédica de Michoacán - Instituto Mexicano del Seguro Social Morelia, Mexico
| | - Anthony E Kline
- Physical Medicine & Rehabilitation, University of Pittsburgh, Pittsburgh, PA 15213, United States; Safar Center for Resuscitation Research, University of Pittsburgh, Pittsburgh, PA 15213, United States; Center for Neuroscience, University of Pittsburgh, Pittsburgh, PA 15213, United States; Center for the Neural Basis of Cognition, University of Pittsburgh, Pittsburgh, PA 15213, United States; Critical Care Medicine, University of Pittsburgh, Pittsburgh, PA 15213, United States; Psychology, University of Pittsburgh, Pittsburgh, PA 15213, United States.
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