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Chalençon L, Midroit M, Athanassi A, Thevenet M, Breton M, Forest J, Richard M, Didier A, Mandairon N. Age-related differences in perception and coding of attractive odorants in mice. Neurobiol Aging 2024; 137:8-18. [PMID: 38394723 DOI: 10.1016/j.neurobiolaging.2024.02.003] [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: 07/19/2023] [Revised: 01/23/2024] [Accepted: 02/11/2024] [Indexed: 02/25/2024]
Abstract
Hedonic perception deeply changes with aging, significantly impacting health and quality of life in elderly. In young adult mice, an odor hedonic signature is represented along the antero-posterior axis of olfactory bulb, and transferred to the olfactory tubercle and ventral tegmental area, promoting approach behavior. Here, we show that while the perception of unattractive odorants was unchanged in older mice (22 months), the appreciation of some but not all attractive odorants declined. Neural activity in the olfactory bulb and tubercle of older mice was consistently altered when attraction to pleasant odorants was impaired while maintained when the odorants kept their attractivity. Finally, in a self-stimulation paradigm, optogenetic stimulation of the olfactory bulb remained rewarding in older mice even without ventral tegmental area's response to the stimulation. Aging degrades behavioral and neural responses to some pleasant odorants but rewarding properties of olfactory bulb stimulation persisted, providing new insights into developing novel olfactory training strategies to elicit motivation even when the dopaminergic system is altered as observed in normal and/or neurodegenerative aging.
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Affiliation(s)
- Laura Chalençon
- CNRS, UMR 5292, France; INSERM, U1028, France; Lyon Neuroscience Research Center, Neuroplasticity and neuropathology of olfactory perception Team, University Lyon1, F-69000, France
| | - Maëllie Midroit
- CNRS, UMR 5292, France; INSERM, U1028, France; Lyon Neuroscience Research Center, Neuroplasticity and neuropathology of olfactory perception Team, University Lyon1, F-69000, France
| | - Anna Athanassi
- CNRS, UMR 5292, France; INSERM, U1028, France; Lyon Neuroscience Research Center, Neuroplasticity and neuropathology of olfactory perception Team, University Lyon1, F-69000, France
| | - Marc Thevenet
- CNRS, UMR 5292, France; INSERM, U1028, France; Lyon Neuroscience Research Center, Neuroplasticity and neuropathology of olfactory perception Team, University Lyon1, F-69000, France
| | - Marine Breton
- CNRS, UMR 5292, France; INSERM, U1028, France; Lyon Neuroscience Research Center, Neuroplasticity and neuropathology of olfactory perception Team, University Lyon1, F-69000, France
| | - Jérémy Forest
- CNRS, UMR 5292, France; INSERM, U1028, France; Lyon Neuroscience Research Center, Neuroplasticity and neuropathology of olfactory perception Team, University Lyon1, F-69000, France
| | - Marion Richard
- CNRS, UMR 5292, France; INSERM, U1028, France; Lyon Neuroscience Research Center, Neuroplasticity and neuropathology of olfactory perception Team, University Lyon1, F-69000, France
| | - Anne Didier
- CNRS, UMR 5292, France; INSERM, U1028, France; Lyon Neuroscience Research Center, Neuroplasticity and neuropathology of olfactory perception Team, University Lyon1, F-69000, France; Institut Universitaire de France (IUF), France
| | - Nathalie Mandairon
- CNRS, UMR 5292, France; INSERM, U1028, France; Lyon Neuroscience Research Center, Neuroplasticity and neuropathology of olfactory perception Team, University Lyon1, F-69000, France.
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2
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Zhao J, Zhang G, Xu D. The effect of reward on motor learning: different stage, different effect. Front Hum Neurosci 2024; 18:1381935. [PMID: 38532789 PMCID: PMC10963647 DOI: 10.3389/fnhum.2024.1381935] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2024] [Accepted: 02/29/2024] [Indexed: 03/28/2024] Open
Abstract
Motor learning is a prominent and extensively studied subject in rehabilitation following various types of neurological disorders. Motor repair and rehabilitation often extend over months and years post-injury with a slow pace of recovery, particularly affecting the fine movements of the distal extremities. This extended period can diminish the motivation and persistence of patients, a facet that has historically been overlooked in motor learning until recent years. Reward, including monetary compensation, social praise, video gaming, music, and virtual reality, is currently garnering heightened attention for its potential to enhance motor motivation and improve function. Numerous studies have examined the effects and attempted to explore potential mechanisms in various motor paradigms, yet they have yielded inconsistent or even contradictory results and conclusions. A comprehensive review is necessary to summarize studies on the effects of rewards on motor learning and to deduce a central pattern from these existing studies. Therefore, in this review, we initially outline a framework of motor learning considering two major types, two major components, and three stages. Subsequently, we summarize the effects of rewards on different stages of motor learning within the mentioned framework and analyze the underlying mechanisms at the level of behavior or neural circuit. Reward accelerates learning speed and enhances the extent of learning during the acquisition and consolidation stages, possibly by regulating the balance between the direct and indirect pathways (activating more D1-MSN than D2-MSN) of the ventral striatum and by increasing motor dynamics and kinematics. However, the effect varies depending on several experimental conditions. During the retention stage, there is a consensus that reward enhances both short-term and long-term memory retention in both types of motor learning, attributed to the LTP learning mechanism mediated by the VTA-M1 dopaminergic projection. Reward is a promising enhancer to bolster waning confidence and motivation, thereby increasing the efficiency of motor learning and rehabilitation. Further exploration of the circuit and functional connections between reward and the motor loop may provide a novel target for neural modulation to promote motor behavior.
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Affiliation(s)
- Jingwang Zhao
- School of Rehabilitation Science, Shanghai University of Traditional Chinese Medicine, Shanghai, China
- Institute of Rehabilitation Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Guanghu Zhang
- School of Rehabilitation Science, Shanghai University of Traditional Chinese Medicine, Shanghai, China
- Institute of Rehabilitation Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Dongsheng Xu
- School of Rehabilitation Science, Shanghai University of Traditional Chinese Medicine, Shanghai, China
- Institute of Rehabilitation Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai, China
- Engineering Research Center of Traditional Chinese Medicine Intelligent Rehabilitation, Ministry of Education, Shanghai, China
- Department of Rehabilitation Medicine, Shuguang Hospital, Shanghai, China
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3
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Siracusa ER, Higham JP, Snyder-Mackler N, Brent LJN. Social ageing: exploring the drivers of late-life changes in social behaviour in mammals. Biol Lett 2022; 18:20210643. [PMID: 35232274 PMCID: PMC8889194 DOI: 10.1098/rsbl.2021.0643] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Social interactions help group-living organisms cope with socio-environmental challenges and are central to survival and reproductive success. Recent research has shown that social behaviour and relationships can change across the lifespan, a phenomenon referred to as 'social ageing'. Given the importance of social integration for health and well-being, age-dependent changes in social behaviour can modulate how fitness changes with age and may be an important source of unexplained variation in individual patterns of senescence. However, integrating social behaviour into ageing research requires a deeper understanding of the causes and consequences of age-based changes in social behaviour. Here, we provide an overview of the drivers of late-life changes in sociality. We suggest that explanations for social ageing can be categorized into three groups: changes in sociality that (a) occur as a result of senescence; (b) result from adaptations to ameliorate the negative effects of senescence; and/or (c) result from positive effects of age and demographic changes. Quantifying the relative contribution of these processes to late-life changes in sociality will allow us to move towards a more holistic understanding of how and why these patterns emerge and will provide important insights into the potential for social ageing to delay or accelerate other patterns of senescence.
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Affiliation(s)
- Erin R Siracusa
- School of Psychology, Centre for Research in Animal Behaviour, University of Exeter, Exeter, UK
| | - James P Higham
- Department of Anthropology, New York University, New York, NY, USA
| | - Noah Snyder-Mackler
- Center for Evolution and Medicine, Arizona State University, Tempe, AZ, USA.,School of Life Sciences, Arizona State University, Tempe, AZ, USA.,School for Human Evolution and Social Change, Arizona State University, Tempe, AZ, USA
| | - Lauren J N Brent
- School of Psychology, Centre for Research in Animal Behaviour, University of Exeter, Exeter, UK
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4
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Le C, Finger E. Pharmacotherapy for Neuropsychiatric Symptoms in Frontotemporal Dementia. CNS Drugs 2021; 35:1081-1096. [PMID: 34426949 DOI: 10.1007/s40263-021-00854-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 08/08/2021] [Indexed: 10/20/2022]
Abstract
Despite significant progress in the understanding of the frontotemporal dementias (FTDs), there remains no disease-modifying treatment for these conditions, and limited effective symptomatic treatment. Behavioural variant frontotemporal dementia (bvFTD) is the most common FTD syndrome, and is characterized by severe impairments in behaviour, personality and cognition. Neuropsychiatric symptoms are common features of bvFTD but are present in the other FTD syndromes. Current treatment strategies therefore focus on ameliorating the neuropsychiatric features. Here we review the rationale for current treatments related to each of the main neuropsychiatric symptoms forming the diagnostic criteria for bvFTD relevant to all FTD subtypes, and two additional symptoms not currently part of the diagnostic criteria: lack of insight and psychosis. Given the paucity of effective treatments for these symptoms, we highlight how contributing mechanisms delineated in cognitive neuroscience may inform future approaches to clinical trials and more precise symptomatic treatments for FTDs.
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Affiliation(s)
- Christine Le
- Department of Clinical Neurological Sciences, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada
| | - Elizabeth Finger
- Department of Clinical Neurological Sciences, Schulich School of Medicine and Dentistry, University of Western Ontario, London, Ontario, Canada.
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5
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How did I do it then? How will I do it later? A theoretical review of the impact of mental time travel on decision-making processes. NEW IDEAS IN PSYCHOLOGY 2021. [DOI: 10.1016/j.newideapsych.2021.100869] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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6
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Wang S, Huang G, Yan J, Li C, Feng J, Chen Q, Zheng X, Li H, Li J, Wang L, Li H. Influence of aging on chronic unpredictable mild stress-induced depression-like behavior in male C57BL/6J mice. Behav Brain Res 2021; 414:113486. [PMID: 34302872 DOI: 10.1016/j.bbr.2021.113486] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2021] [Revised: 06/11/2021] [Accepted: 07/19/2021] [Indexed: 12/27/2022]
Abstract
Depression is a common psychiatric disorder that can occur throughout an individual's lifespan. Chronic unpredictable mild stress (CUMS) protocol is currently the most commonly used to develop an animal model of depression. Due to the variable duration and procedure of CUMS, it is difficult to reproduce and explore the mechanism of CUMS-induced depression effectively. In the present study, the CUMS-induced behavioral phenotypes were assessed in male C57BL/6J mice at the age of 9-18 weeks. The mice stressed for 3-8 weeks exhibited lower body weight as well as longer immobility time of forced swim and tail suspension test compared to control mice. Moreover, lessening and impairment of hippocampal neurons was found in stressed mice at the age of 18 weeks, which was correlated with increased relative mRNA expression levels of inflammatory cytokines BDNF, Htr1a, and IL-6 in the hippocampus. Nevertheless, no difference between stressed and control mice was observed neither in the sucrose preference nor in the open field test (except for vertical activity in OFT) at the age of 18 weeks. These findings reveal that 3-8 weeks of chronic stress could induce depression-like alterations in male C57BL/6J mice and the behavioral adaptation of aged mice might fail to the availability of the depression model.
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Affiliation(s)
- Sheng Wang
- School of Life Sciences and Biopharmaceuticals, Guangdong Pharmaceutical University, Guangzhou, 510006, China
| | - Guilan Huang
- The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, 510080, China
| | - Jie Yan
- School of Pharmacy, Guangdong Pharmaceutical University, Guangzhou, 510006, China
| | - Changxi Li
- School of Clinical Medicine, Guangdong Pharmaceutical University, Guangzhou, 510006, China
| | - Jianwen Feng
- School of Pharmacy, Guangdong Pharmaceutical University, Guangzhou, 510006, China
| | - Qi Chen
- School of Pharmacy, Guangdong Pharmaceutical University, Guangzhou, 510006, China
| | - Xiaomeng Zheng
- School of Pharmacy, Guangdong Pharmaceutical University, Guangzhou, 510006, China
| | - Haobin Li
- School of Life Sciences and Biopharmaceuticals, Guangdong Pharmaceutical University, Guangzhou, 510006, China
| | - Jiangchao Li
- Guangdong Province Key Laboratory for Biotechnology Drug Candidates, Guangdong Pharmaceutical University, Guangzhou, 510006, China
| | - Lijing Wang
- School of Life Sciences and Biopharmaceuticals, Guangdong Pharmaceutical University, Guangzhou, 510006, China
| | - Huimin Li
- Department of Applied Psychology, School of Humanities and Communication, Guangdong University of Finance & Economics, Guangzhou, 510320, China.
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7
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Pocuca N, Walter TJ, Minassian A, Young JW, Geyer MA, Perry W. The Effects of Cannabis Use on Cognitive Function in Healthy Aging: A Systematic Scoping Review. Arch Clin Neuropsychol 2021; 36:673-685. [PMID: 33159510 DOI: 10.1093/arclin/acaa105] [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] [Accepted: 10/01/2020] [Indexed: 12/25/2022] Open
Abstract
BACKGROUND Older adults (≥50 years) represent the fastest-growing population of people who use cannabis, potentially due to the increasing promotion of cannabis as medicine by dispensaries and cannabis websites. Given healthy aging and cannabis use are both associated with cognitive decline, it is important to establish the effects of cannabis on cognition in healthy aging. OBJECTIVE This systematic scoping review used preferred reporting items for systematic reviews and meta-analyses guidelines to critically examine the extent of literature on this topic and highlight areas for future research. METHOD A search of six databases (PubMed, EMBASE, PsycINFO, Web of Science, Family and Society Studies Worldwide, and CINAHL) for articles published by September 2019, yielded 1,014 unique results. RESULTS Six articles reported findings for older populations (three human and three rodent studies), highlighting the paucity of research in this area. Human studies revealed largely null results, likely due to several methodological limitations. Better-controlled rodent studies indicate that the relationship between ∆9-tetrahydrocannabinol (THC) and cognitive function in healthy aging depends on age and level of THC exposure. Extremely low doses of THC improved cognition in very old rodents. Somewhat higher chronic doses improved cognition in moderately aged rodents. No studies examined the effects of cannabidiol (CBD) or high-CBD cannabis on cognition. CONCLUSIONS This systematic scoping review provides crucial, timely direction for future research on this emerging issue. Future research that combines neuroimaging and cognitive assessment would serve to advance understanding of the effects of age and quantity of THC and CBD on cognition in healthy aging.
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Affiliation(s)
- Nina Pocuca
- Department of Psychiatry, University of California San Diego, San Diego, CA, USA
| | - T Jordan Walter
- Department of Psychiatry, University of California San Diego, San Diego, CA, USA
| | - Arpi Minassian
- Department of Psychiatry, University of California San Diego, San Diego, CA, USA.,Center for Stress and Mental Health, Veteran's Administration San Diego Hospital, San Diego, CA, USA
| | - Jared W Young
- Department of Psychiatry, University of California San Diego, San Diego, CA, USA.,Research Service, VA San Diego Healthcare System, San Diego, CA, USA
| | - Mark A Geyer
- Department of Psychiatry, University of California San Diego, San Diego, CA, USA.,Research Service, VA San Diego Healthcare System, San Diego, CA, USA
| | - William Perry
- Department of Psychiatry, University of California San Diego, San Diego, CA, USA
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8
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Wiegand I, Wolfe JM. Target value and prevalence influence visual foraging in younger and older age. Vision Res 2021; 186:87-102. [PMID: 34062375 DOI: 10.1016/j.visres.2021.05.001] [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] [Received: 12/18/2020] [Revised: 05/04/2021] [Accepted: 05/07/2021] [Indexed: 01/13/2023]
Abstract
The prevalence and reward-value of targets have an influence on visual search. The strength of the effect of an item's reward-value on attentional selection varies substantially between individuals and is potentially sensitive to aging. We investigated individual and age differences in a hybrid foraging task, in which the prevalence and value of multiple target types was varied. Using optimal foraging theory measures, foraging was more efficient overall in younger than older observers. However, the influence of prevalence and value on target selections was similar across age groups, suggesting that the underlying cognitive mechanisms are preserved in older age. When prevalence was varied but target value was balanced, younger and older observers preferably selected the most frequent target type and were biased to select another instance of the previously selected target type. When value was varied, younger and older observers showed a tendency to select high-value targets, but preferences were more diverse between individuals. When value and prevalence were inversely related, some observers showed particularly strong preferences for high-valued target types, while others showed a preference for high-prevalent, albeit low-value, target types. In younger adults, individual differences in the selection choices correlated with a personality index, suggesting that avoiding selections of low-value targets may be related to reward-seeking behaviour.
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Affiliation(s)
- Iris Wiegand
- Donders Institute for Brain, Cognition and Behavior, Department of Neuropsychology and Rehabilitation Psychology, Radboud University, Nijmegen, Netherlands; Visual Attention Lab, Brigham & Women's Hospital, Harvard Medical School, Boston, MA, USA.
| | - Jeremy M Wolfe
- Visual Attention Lab, Brigham & Women's Hospital, Harvard Medical School, Boston, MA, USA; Departments of Ophthalmology & Radiology, Harvard Medical School, Boston, MA, USA
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de Haan T, van den Berg B, Woldorff MG, Aleman A, Lorist MM. Diminished Feedback Evaluation and Knowledge Updating Underlying Age-Related Differences in Choice Behavior During Feedback Learning. Front Hum Neurosci 2021; 15:635996. [PMID: 33746726 PMCID: PMC7973460 DOI: 10.3389/fnhum.2021.635996] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Accepted: 02/02/2021] [Indexed: 11/16/2022] Open
Abstract
In our daily lives, we continuously evaluate feedback information, update our knowledge, and adapt our behavior in order to reach desired goals. This ability to learn from feedback information, however, declines with age. Previous research has indicated that certain higher-level learning processes, such as feedback evaluation, integration of feedback information, and updating of knowledge, seem to be affected by age, and recent studies have shown how the adaption of choice behavior following feedback can differ with age. The neural mechanisms underlying this age-related change in choice behavior during learning, however, remain unclear. The aim of this study is therefore to investigate the relation between learning-related neural processes and choice behavior during feedback learning in two age groups. Behavioral and fMRI data were collected, while a group of young (age 18–30) and older (age 60–75) adults performed a probabilistic learning task consisting of 10 blocks of 20 trials each. On each trial, the participants chose between a house and a face, after which they received visual feedback (loss vs. gain). In each block, either the house or the face image had a higher probability of yielding a reward (62.5 vs. 37.5%). Participants were instructed to try to maximize their gains. Our results showed that less successful learning in older adults, as indicated by a lower learning rate, corresponded with a higher tendency to switch to the other stimulus option, and with a reduced adaptation of this switch choice behavior following positive feedback. At the neural level, activation following positive and negative feedback was found to be less distinctive in the older adults, due to a smaller feedback-evaluation response to positive feedback in this group. Furthermore, whereas young adults displayed increased levels of knowledge updating prior to adapting choice behavior, we did not find this effect in older adults. Together, our results suggest that diminished learning performance with age corresponds with diminished evaluation of positive feedback and reduced knowledge updating related to changes in choice behavior, indicating how such differences in feedback processing at the trial level in older adults might lead to reduced learning performance across trials.
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Affiliation(s)
- Tineke de Haan
- Department of Experimental Psychology, University of Groningen, Groningen, Netherlands
| | - Berry van den Berg
- Department of Experimental Psychology, University of Groningen, Groningen, Netherlands
| | - Marty G Woldorff
- Center for Cognitive Neuroscience, Duke University, Durham, NC, United States
| | - André Aleman
- Department of Biomedical Sciences of Cells and Systems, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
| | - Monicque M Lorist
- Department of Experimental Psychology, University of Groningen, Groningen, Netherlands.,Department of Biomedical Sciences of Cells and Systems, University Medical Center Groningen, University of Groningen, Groningen, Netherlands
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Appetite Control across the Lifecourse: The Acute Impact of Breakfast Drink Quantity and Protein Content. The Full4Health Project. Nutrients 2020; 12:nu12123710. [PMID: 33266325 PMCID: PMC7759987 DOI: 10.3390/nu12123710] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Revised: 11/25/2020] [Accepted: 11/27/2020] [Indexed: 12/11/2022] Open
Abstract
Understanding the mechanisms of hunger, satiety and how nutrients affect appetite control is important for successful weight management across the lifecourse. The primary aim of this study was to describe acute appetite control across the lifecourse, comparing age groups (children, adolescents, adults, elderly), weight categories, genders and European sites (Scotland and Greece). Participants (n = 391) consumed four test drinks, varying in composition (15% (normal protein, NP) and 30% (high protein, HP) of energy from protein) and quantity (based on 100% basal metabolic rate (BMR) and 140% BMR), on four separate days in a double-blind randomized controlled study. Ad libitum energy intake (EI), subjective appetite and biomarkers of appetite and metabolism (adults and elderly only) were measured. The adults' appetite was significantly greater than that of the elderly across all drink types (p < 0.004) and in response to drink quantities (p < 0.001). There were no significant differences in EI between age groups, weight categories, genders or sites. Concentrations of glucagon-like peptide 1 (GLP-1) and peptide YY (PYY) were significantly greater in the elderly than the adults (p < 0.001). Ghrelin and fasting leptin concentrations differed significantly between weight categories, genders and sites (p < 0.05), while GLP-1 and PYY concentrations differed significantly between genders only (p < 0.05). Compared to NP drinks, HP drinks significantly increased postprandial GLP-1 and PYY (p < 0.001). Advanced age was concomitant with reduced appetite and elevated anorectic hormone release, which may contribute to the development of malnutrition. In addition, appetite hormone concentrations differed between weight categories, genders and geographical locations.
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Proskovec AL, Rezich MT, O’Neill J, Morsey B, Wang T, Ideker T, Swindells S, Fox HS, Wilson TW. Association of Epigenetic Metrics of Biological Age With Cortical Thickness. JAMA Netw Open 2020; 3:e2015428. [PMID: 32926115 PMCID: PMC7490648 DOI: 10.1001/jamanetworkopen.2020.15428] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
IMPORTANCE Magnetic resonance imaging (MRI) studies of aging adults have shown substantial intersubject variability across various brain metrics, and some of this variability is likely attributable to chronological age being an imprecise measure of age-related change. Accurately quantifying one's biological age could allow better quantification of healthy and pathological changes in the aging brain. OBJECTIVE To investigate the association of DNA methylation (DNAm)-based biological age with cortical thickness and to assess whether biological age acceleration compared with chronological age captures unique variance in cortical thinning. DESIGN, SETTING, AND PARTICIPANTS This cross-sectional study used high-resolution structural brain MRI data collected from a sample of healthy aging adults who were participating in a larger ongoing neuroimaging study that began in May 2014. This population-based study accrued participants from the greater Omaha, Nebraska, metropolitan area. One hundred sixty healthy adults were contacted for the MRI component, 82 of whom participated in both DNAm and MRI study components. Data analysis was performed from March to June 2019. MAIN OUTCOMES AND MEASURES Vertexwise cortical thickness, DNAm-based biological age, and biological age acceleration compared with chronological age were measured. A pair of multivariable regression models were computed in which cortical thickness was regressed on DNAm-based biological age, controlling for sex in the first model and also controlling for chronological age in the second model. RESULTS Seventy-nine adult participants (38 women; mean [SD] age, 43.82 [14.50] years; age range, 22-72 years) were included in all final analyses. Advancing biological age was correlated with cortical thinning across frontal, superior temporal, inferior parietal, and medial occipital regions. In addition, biological age acceleration relative to chronological age was associated with cortical thinning in orbitofrontal, superior and inferior temporal, somatosensory, parahippocampal, and fusiform regions. Specifically, for every 1 year of biological age acceleration, cortical thickness would be expected to decrease by 0.024 mm (95% CI, -0.04 to -0.01 mm) in the left orbitofrontal cortex (partial r, -0.34; P = .002), 0.014 mm (95% CI, -0.02 to -0.01 mm) in the left superior temporal gyrus (partial r, -0.36; P = .001), 0.015 mm (95% CI, -0.02 to -0.01 mm) in the left fusiform gyrus (partial r, -0.38; P = .001), 0.015 mm (95% CI, -0.02 to -0.01 mm) in the right fusiform gyrus (partial r, -0.43; P < .001), 0.019 mm (95% CI, -0.03 to -0.01 mm) in the right inferior temporal sulcus (partial r, -0.34; P = .002), and 0.011 mm (95% CI, -0.02 to -0.01 mm) in the right primary somatosensory cortex (partial r, -0.37; P = .001). CONCLUSIONS AND RELEVANCE To our knowledge, this is the first study to investigate vertexwise cortical thickness in relation to DNAm-based biological age, and the findings suggest that this metric of biological age may yield additional insight on healthy and pathological cortical aging compared with standard measures of chronological age alone.
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Affiliation(s)
- Amy L. Proskovec
- Center for Magnetoencephalography, University of Nebraska Medical Center, Omaha
- Department of Neurological Sciences, University of Nebraska Medical Center, Omaha
- Department of Psychology, University of Nebraska Omaha, Omaha
- Magnetoencephalography Center of Excellence, University of Texas Southwestern Medical Center, Dallas
| | - Michael T. Rezich
- Center for Magnetoencephalography, University of Nebraska Medical Center, Omaha
- Department of Neurological Sciences, University of Nebraska Medical Center, Omaha
| | - Jennifer O’Neill
- Department of Internal Medicine, Division of Infectious Diseases, University of Nebraska Medical Center, Omaha
| | - Brenda Morsey
- Department of Neurological Sciences, University of Nebraska Medical Center, Omaha
| | - Tina Wang
- Department of Medicine, University of California San Diego, La Jolla
| | - Trey Ideker
- Department of Medicine, University of California San Diego, La Jolla
| | - Susan Swindells
- Department of Internal Medicine, Division of Infectious Diseases, University of Nebraska Medical Center, Omaha
| | - Howard S. Fox
- Department of Neurological Sciences, University of Nebraska Medical Center, Omaha
| | - Tony W. Wilson
- Center for Magnetoencephalography, University of Nebraska Medical Center, Omaha
- Department of Neurological Sciences, University of Nebraska Medical Center, Omaha
- Department of Psychology, University of Nebraska Omaha, Omaha
- Cognitive Neuroscience of Development & Aging Center, University of Nebraska Medical Center, Omaha
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12
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Age-Related Differences in Motivational Integration and Cognitive Control. COGNITIVE AFFECTIVE & BEHAVIORAL NEUROSCIENCE 2020; 19:692-714. [PMID: 30980339 DOI: 10.3758/s13415-019-00713-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Motivational incentives play an influential role in value-based decision-making and cognitive control. A compelling hypothesis in the literature suggests that the motivational value of diverse incentives are integrated in the brain into a common currency value signal that influences decision-making and behavior. To investigate whether motivational integration processes change during healthy aging, we tested older (N = 44) and younger (N = 54) adults in an innovative incentive integration task paradigm that establishes dissociable and additive effects of liquid (e.g., juice, neutral, saltwater) and monetary incentives on cognitive task performance. The results reveal that motivational incentives improve cognitive task performance in both older and younger adults, providing novel evidence demonstrating that age-related cognitive control deficits can be ameliorated with sufficient incentive motivation. Additional analyses revealed clear age-related differences in motivational integration. Younger adult task performance was modulated by both monetary and liquid incentives, whereas monetary reward effects were more gradual in older adults and more strongly impacted by trial-by-trial performance feedback. A surprising discovery was that older adults shifted attention from liquid valence toward monetary reward throughout task performance, but younger adults shifted attention from monetary reward toward integrating both monetary reward and liquid valence by the end of the task, suggesting differential strategic utilization of incentives. These data suggest that older adults may have impairments in incentive integration and employ different motivational strategies to improve cognitive task performance. The findings suggest potential candidate neural mechanisms that may serve as the locus of age-related change, providing targets for future cognitive neuroscience investigations.
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Le TM, Chao H, Levy I, Li CSR. Age-Related Changes in the Neural Processes of Reward-Directed Action and Inhibition of Action. Front Psychol 2020; 11:1121. [PMID: 32587547 PMCID: PMC7298110 DOI: 10.3389/fpsyg.2020.01121] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2020] [Accepted: 04/30/2020] [Indexed: 01/31/2023] Open
Abstract
Aging is associated with structural and functional brain changes which may impact the regulation of motivated behaviors, including both action and inhibition of action. As behavioral regulation is often exercised in response to reward, it remains unclear how aging may influence reward-directed action and inhibition of action differently. Here we addressed this issue with the functional magnetic resonance imaging data of 72 participants (aged 21-74) performing a reward go/no-go (GNG) task with approximately 2/3 go and 1/3 no-go trials. The go and no-go success trials were rewarded with a dollar or a nickel, and the incorrect responses were penalized. An additional block of the GNG task without reward/punishment served as the control to account for age-related slowing in processing speed. The results showed a prolonged response time (RT) in rewarded (vs. control) go trials with increasing age. Whole-brain multiple regressions of rewarded (vs. control) go trials against age and RT both revealed an age-related reduced activity of the anterior insula, middle frontal gyrus, and rostral anterior cingulate cortex. Furthermore, activity from these regions mediated the relationship between age and go performance. During rewarded (vs. control) no-go trials, age was associated with increased accuracy rate but decreased activation in the medial superior frontal and postcentral gyri. As these regions also exhibited age-related activity reduction during rewarded go, the finding suggests aging effects on common brain substrates that regulate both action and action inhibition. Taken together, age shows a broad negative modulation on neural activations but differential effects on performance during rewarded action and inhibition of action.
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Affiliation(s)
- Thang M. Le
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, United States
| | - Herta Chao
- Department of Medicine, Yale University School of Medicine, New Haven, CT, United States
- VA Connecticut Healthcare System, West Haven, CT, United States
| | - Ifat Levy
- Department of Comparative Medicine, Yale University School of Medicine, New Haven, CT, United States
- Department of Neuroscience, Yale University School of Medicine, New Haven, CT, United States
- Interdepartmental Neuroscience Program, Yale University School of Medicine, New Haven, CT, United States
| | - Chiang-Shan R. Li
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, United States
- Department of Neuroscience, Yale University School of Medicine, New Haven, CT, United States
- Interdepartmental Neuroscience Program, Yale University School of Medicine, New Haven, CT, United States
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14
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Ferdinand NK, Hilz M. Emotional feedback ameliorates older adults' feedback-induced learning. PLoS One 2020; 15:e0231964. [PMID: 32352992 PMCID: PMC7192411 DOI: 10.1371/journal.pone.0231964] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Accepted: 04/03/2020] [Indexed: 01/17/2023] Open
Abstract
In older age, learning and feedback processing are usually impaired. This is thought to be due to impairments in the dopaminergic system and the anterior cingulate cortex. By contrast, processing of affective information seems to remain relatively intact. Recent research has also demonstrated that cognitive functioning can be influenced by affective materials or contexts and lead to an enhancement in diverse cognitive tasks. Hence, the aim of the present study was to explore, whether emotional feedback would counteract age-related learning deficits and strengthen early and later phases of feedback processing as reflected in the feedback-related negativity (FRN) and P3b of the event-related potential (ERP). Younger and older participants conducted a probabilistic reinforcement learning task in which the accurate responses had to be learned via feedback. In emotional trials, feedback stimuli consisted of faces with smiling and disgusted expressions, and in a non-emotional condition, positive and negative feedback was indicated by the background color of faces with neutral expressions. Our main results were that older adults showed better learning performance in the emotional feedback condition and a larger P3b after emotional than non-emotional feedback indexing heightened working memory updating after task relevant events.
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Affiliation(s)
- Nicola K. Ferdinand
- Department of Psychology, Bergische Universität Wuppertal, Wuppertal, Germany
- Department of Psychology, Saarland University, Saarbrücken, Germany
| | - Melanie Hilz
- Department of Psychology, Saarland University, Saarbrücken, Germany
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15
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Aiello M, Parma V, De Carlo S, Hummel T, Rumiati RI. Cognitive, Olfactory, and Affective Determinants of Body Weight in Aging Individuals. Arch Clin Neuropsychol 2020; 34:637-647. [PMID: 30272124 DOI: 10.1093/arclin/acy072] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Revised: 07/12/2018] [Accepted: 08/09/2018] [Indexed: 11/13/2022] Open
Abstract
OBJECTIVE A complex interplay of factors including cognitive, sensory and affective aspects has been associated in a controversial way with anthropometric measures related to body weight. METHODS Here we propose two studies to investigate whether and how cognitive, olfactory and affective variables resulted associated with body weight during healthy aging. In Study 1, we investigated the cognitive status, the odor identification skills, and the BMI of 209 individuals (50-96 yo). In Study 2 an extensive evaluation of cognitive functions (in particular executive functions and memory), odor threshold, discrimination and identification and affective skills (i.e., depression and anxiety) was performed in a group of 35 healthy, free-living aging individuals (58-85 yo). RESULTS In Study 1, greater BMI was not associated with performance on the odor identification task but was significantly associated with better cognitive skills. In Study 2, we observed that executive functions seemed to favor a successful managing of body weight, and individuals with greater BMI and waist circumference showed significantly better odor discrimination skills. Finally, lower waist circumference (but not BMI) was found significantly associated with greater levels of anxiety. CONCLUSIONS These results confirm that cognitive, olfactory and affective factors may influence body weight during healthy aging.
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Affiliation(s)
| | - Valentina Parma
- Area of Neuroscience, SISSA, Trieste, Italy.,Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden.,William James Research Center, Lisbon, Portugal
| | | | - Thomas Hummel
- Smell & Taste Clinic, Department of Otorhinolaryngology, TU Dresden, Dresden, Germany
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16
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Circadian modulation of motivation in mice. Behav Brain Res 2020; 382:112471. [PMID: 31958519 DOI: 10.1016/j.bbr.2020.112471] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Revised: 01/03/2020] [Accepted: 01/04/2020] [Indexed: 11/21/2022]
Abstract
Most living organisms have a circadian timing system adapted to optimize the daily rhythm of exposure to the environment. This circadian system modulates several behavioral and physiological processes, including the response to natural and drug rewards. Food is the most potent natural reward across species. Food-seeking is known to be mediated by dopaminergic and serotonergic transmission in cortico-limbic pathways. In the present work, we show evidence of a circadian modulation of motivation for food reward in young (4-months old) and aged (over 1.5 years old) C57BL/6 mice. Motivation was assayed through the progressive ratio (PR) schedule. Mice under a 12:12 light/dark (LD) cycle exhibited a diurnal rhythm in motivation, becoming more motivated during the night, coincident with their active phase. This rhythm was also evident under constant dark conditions, indicating the endogenous nature of this modulation. However, circadian arrhythmicity induced by chronic exposure to constant light conditions impaired the performance in the task causing low motivation levels. Furthermore, the day/night difference in motivation was also evident even without caloric restriction when using a palatable reward. All these results were found to be unaffected by aging. Taken together, our results indicate that motivation for food reward is regulated in a circadian manner, independent of the nutritional status and the nature of the reward, and that this rhythmic modulation is not affected by aging. These results may contribute to improve treatment related to psychiatric disorders or drugs of abuse, taking into account potential mechanisms of circadian modulation of motivational states.
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17
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Gür E, Duyan YA, Arkan S, Karson A, Balcı F. Interval timing deficits and their neurobiological correlates in aging mice. Neurobiol Aging 2020; 90:33-42. [PMID: 32220513 DOI: 10.1016/j.neurobiolaging.2020.02.021] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Revised: 01/27/2020] [Accepted: 02/22/2020] [Indexed: 11/24/2022]
Abstract
Age-related neurobiological and cognitive alterations suggest that interval timing (as a related function) is also altered in aging, which can, in turn, disrupt timing-dependent functions. We investigated alterations in interval timing with aging and accompanying neurobiological changes. We tested 4-6, 10-12, and 18-20 month-old mice on the dual peak interval procedure. Results revealed a specific deficit in the termination of timed responses (stop-times). The decision processes contributed more to timing variability (vs. clock/memory process) in the aged mice. We observed age-dependent reductions in the number of dopaminergic neurons in the VTA and SNc, cholinergic neurons in the medial septum/diagonal band (MS/DB) complex, and density of dopaminergic axon terminals in the DLS/DMS. Negative correlations were found between the number of dopaminergic neurons in the VTA and stop times, and the number of cholinergic neurons in MS/DB complex and the acquisition of stop times. Our results point at age-dependent changes in the decisional components of interval timing and the role of dopaminergic and cholinergic functions in these behavioral alterations.
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Affiliation(s)
- Ezgi Gür
- Timing and Decision-Making Laboratory, Department of Psychology, Koç University, Istanbul, Turkey; Koç University Research Center for Translational Medicine, Istanbul, Turkey
| | - Yalçın Akın Duyan
- Timing and Decision-Making Laboratory, Department of Psychology, Koç University, Istanbul, Turkey; Koç University Research Center for Translational Medicine, Istanbul, Turkey
| | - Sertan Arkan
- Timing and Decision-Making Laboratory, Department of Psychology, Koç University, Istanbul, Turkey; Koç University Research Center for Translational Medicine, Istanbul, Turkey; Kocaeli University, Physiology Department, Umuttepe Campus, Kocaeli, Turkey
| | - Ayşe Karson
- Kocaeli University, Physiology Department, Umuttepe Campus, Kocaeli, Turkey
| | - Fuat Balcı
- Timing and Decision-Making Laboratory, Department of Psychology, Koç University, Istanbul, Turkey; Koç University Research Center for Translational Medicine, Istanbul, Turkey.
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18
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Dhingra I, Zhang S, Zhornitsky S, Le TM, Wang W, Chao HH, Levy I, Li CSR. The effects of age on reward magnitude processing in the monetary incentive delay task. Neuroimage 2020; 207:116368. [PMID: 31743790 PMCID: PMC7463276 DOI: 10.1016/j.neuroimage.2019.116368] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Revised: 11/11/2019] [Accepted: 11/15/2019] [Indexed: 12/28/2022] Open
Abstract
Previous studies have suggested age-related differences in reward-directed behavior and cerebral processes in support of the age effects. However, it remains unclear how age may influence the processing of reward magnitude. Here, with 54 volunteers (22-74 years of age) participating in the Monetary Incentive Delay Task (MIDT) with explicit cues ($1, ¢1, or nil) and timed response to win, we characterized brain activations during anticipation and feedback and the effects of age on these regional activations. Behaviorally, age was associated with less reaction time (RT) difference between dollar and cent trials, as a result of slower response to the dollar trials; i.e., age was positively correlated with RT dollar - RT cent, with RT nil as a covariate. Both age and the RT difference ($1 - ¢1) were correlated with diminished activation of the right caudate head, right anterior insula, supplementary motor area (SMA)/pre-SMA, visual cortex, parahippocampal gyrus, right superior/middle frontal gyri, and left primary motor cortex during anticipation of $1 vs. ¢1 reward. Further, these regional activities mediated the age effects on RT differences. In responses to outcomes, age was associated with decreases in regional activations to dollar vs. cent loss but only because of higher age-related responses to cent losses. Together, these findings suggest age-related differences in sensitivity to the magnitude of reward. With lower cerebral responses during anticipation to win large rewards and higher responses to outcomes of small loss, aging incurs a constricted sensitivity to the magnitude of reward.
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Affiliation(s)
- Isha Dhingra
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
| | - Sheng Zhang
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
| | - Simon Zhornitsky
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
| | - Thang M Le
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
| | - Wuyi Wang
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
| | - Herta H Chao
- Department of Medicine, Yale University School of Medicine, New Haven, CT, USA; VA Connecticut Healthcare System, West Haven, CT, USA
| | - Ifat Levy
- Department of Comparative Medicine, Yale University School of Medicine, New Haven, CT, USA; Department of Neuroscience, Yale University School of Medicine, New Haven, CT, USA; Interdepartmental Neuroscience Program, Yale University, New Haven, CT, USA
| | - Chiang-Shan R Li
- Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA; Department of Neuroscience, Yale University School of Medicine, New Haven, CT, USA; Interdepartmental Neuroscience Program, Yale University, New Haven, CT, USA.
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19
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Lighthall NR. Neural mechanisms of decision-making in aging. WILEY INTERDISCIPLINARY REVIEWS. COGNITIVE SCIENCE 2019; 11:e1519. [PMID: 31608583 DOI: 10.1002/wcs.1519] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Revised: 08/19/2019] [Accepted: 08/21/2019] [Indexed: 01/01/2023]
Abstract
The present review synthesizes findings on decision neuroscience and aging by focusing on decision processes that have been extensively studied in neuroeconomics and critically assessing the driving mechanisms of age-related change. The paper first highlights age-related changes to key brain structures that have been implicated in decision-making, then, reviews specific decision components and discusses investigations of age-related changes to their neural mechanisms. The review also weighs evidence for organic brain aging versus age-related changes to social and psychological factors in mediating age effects. Reviewed findings are discussed in the context of theories and frameworks that have been used to explain trajectories of change in decision-making across adulthood. This article is categorized under: Psychology > Development and Aging Psychology > Reasoning and Decision-Making Neuroscience > Cognition.
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20
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Oizumi H, Kuriyama N, Imamura S, Tabuchi M, Omiya Y, Mizoguchi K, Kobayashi H. Influence of aging on the behavioral phenotypes of C57BL/6J mice after social defeat. PLoS One 2019; 14:e0222076. [PMID: 31479487 PMCID: PMC6719861 DOI: 10.1371/journal.pone.0222076] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2018] [Accepted: 08/21/2019] [Indexed: 12/13/2022] Open
Abstract
Depression and anxiety are common psychiatric disorders that can occur throughout an individual’s lifetime. Numerous pathways underlying the onset of these diseases have been identified in rodents using a social defeat stress protocol, whereby socially defeated individuals exhibit depression- and/or anxiety-like phenotypes that typically manifest as social avoidance behavior. However, most studies in this field have been conducted using young adult mice; therefore, information about social defeat stress-related behavioral phenotypes in older mice is limited. In this study, we exposed groups of young adult (8–16 weeks old) and aged (24 months old) C57BL/6J mice to mild social defeat stress by challenging them with aggressive CD1 mice while restricting the intensity of aggression to protect the animals from severe injuries. We then identified stress-induced behavioral changes and compared their expression between the age groups and with a non-defeated (non-stressed) control group. We found that the stressed mice in both age groups exhibited similar reduced social interactions that were indicative of increased social avoidance behavior. Moreover, unlike the young stressed and control groups, only the aged stressed group showed a reduced preference for sucrose, which was correlated with social avoidance behavior. Also, the aged stressed mice exhibited an attenuated defeat-induced increase in water intake. These findings reveal that aging alters behavioral phenotypes after social defeat and that the hedonic behavior of aged mice is more vulnerable to social defeat compared with younger mice.
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Affiliation(s)
- Hiroaki Oizumi
- Tsumura Kampo Research Laboratories, Tsumura & Co., Ibaraki, Japan
- * E-mail:
| | - Nae Kuriyama
- Tsumura Kampo Research Laboratories, Tsumura & Co., Ibaraki, Japan
| | - Sachiko Imamura
- Tsumura Kampo Research Laboratories, Tsumura & Co., Ibaraki, Japan
| | - Masahiro Tabuchi
- Tsumura Kampo Research Laboratories, Tsumura & Co., Ibaraki, Japan
| | - Yuji Omiya
- Tsumura Kampo Research Laboratories, Tsumura & Co., Ibaraki, Japan
| | | | - Hiroyuki Kobayashi
- Center for Advanced Kampo Medicine and Clinical Research, Juntendo Graduate School of Medicine, Tokyo, Japan
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21
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The influence of task complexity and information value on feedback processing in younger and older adults: No evidence for a positivity bias during feedback-induced learning in older adults. Brain Res 2019; 1717:74-85. [DOI: 10.1016/j.brainres.2019.04.011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Revised: 04/11/2019] [Accepted: 04/12/2019] [Indexed: 12/13/2022]
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22
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Sojitra RB, Lerner I, Petok JR, Gluck MA. Age affects reinforcement learning through dopamine-based learning imbalance and high decision noise-not through Parkinsonian mechanisms. Neurobiol Aging 2018; 68:102-113. [PMID: 29778803 DOI: 10.1016/j.neurobiolaging.2018.04.006] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2017] [Revised: 02/26/2018] [Accepted: 04/11/2018] [Indexed: 11/13/2022]
Abstract
Probabilistic reinforcement learning declines in healthy cognitive aging. While some findings suggest impairments are especially conspicuous in learning from rewards, resembling deficits in Parkinson's disease, others also show impairments in learning from punishments. To reconcile these findings, we tested 252 adults from 3 age groups on a probabilistic reinforcement learning task, analyzed trial-by-trial performance with a Q-reinforcement learning model, and correlated both fitted model parameters and behavior to polymorphisms in dopamine-related genes. Analyses revealed that learning from both positive and negative feedback declines with age but through different mechanisms: when learning from negative feedback, older adults were slower due to noisy decision-making; when learning from positive feedback, they tended to settle for a nonoptimal solution due to an imbalance in learning from positive and negative prediction errors. The imbalance was associated with polymorphisms in the DARPP-32 gene and appeared to arise from mechanisms different from those previously attributed to Parkinson's disease. Moreover, this imbalance predicted previous findings on aging using the Probabilistic Selection Task, which were misattributed to Parkinsonian mechanisms.
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Affiliation(s)
- Ravi B Sojitra
- Center for Molecular and Behavioral Neuroscience, Rutgers University, Newark, Newark, NJ, USA; Department of Mathematics and Computer Science, Rutgers University, Newark, Newark, NJ, USA.
| | - Itamar Lerner
- Center for Molecular and Behavioral Neuroscience, Rutgers University, Newark, Newark, NJ, USA.
| | - Jessica R Petok
- Center for Molecular and Behavioral Neuroscience, Rutgers University, Newark, Newark, NJ, USA; Department of Psychology, St. Olaf-College, Northfield, MN, USA
| | - Mark A Gluck
- Center for Molecular and Behavioral Neuroscience, Rutgers University, Newark, Newark, NJ, USA.
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23
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Talukdar T, Román FJ, Operskalski JT, Zwilling CE, Barbey AK. Individual differences in decision making competence revealed by multivariate fMRI. Hum Brain Mapp 2018. [PMID: 29516582 DOI: 10.1002/hbm.24032] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
While an extensive literature in decision neuroscience has elucidated the neurobiological foundations of decision making, prior research has focused primarily on group-level effects in a sample population. Due to the presence of inherent differences between individuals' cognitive abilities, it is also important to examine the neural correlates of decision making that explain interindividual variability in cognitive performance. This study therefore investigated how individual differences in decision making competence, as measured by the Adult Decision Making Competence (A-DMC) battery, are related to functional brain connectivity patterns derived from resting-state fMRI data in a sample of 304 healthy participants. We examined connectome-wide associations, identifying regions within frontal, parietal, temporal, and occipital cortex that demonstrated significant associations with decision making competence. We then assessed whether the functional interactions between brain regions sensitive to decision making competence and seven intrinsic connectivity networks (ICNs) were predictive of specific facets of decision making assessed by subtests of the A-DMC battery. Our findings suggest that individual differences in specific facets of decision making competence are mediated by ICNs that support executive, social, and perceptual processes, and motivate an integrative framework for understanding the neural basis of individual differences in decision making competence.
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Affiliation(s)
- Tanveer Talukdar
- Decision Neuroscience Laboratory, University of Illinois, Urbana, Illinois.,Beckman Institute for Advanced Science and Technology, University of Illinois, Urbana, Illinois
| | - Francisco J Román
- Decision Neuroscience Laboratory, University of Illinois, Urbana, Illinois.,Beckman Institute for Advanced Science and Technology, University of Illinois, Urbana, Illinois
| | - Joachim T Operskalski
- Decision Neuroscience Laboratory, University of Illinois, Urbana, Illinois.,Beckman Institute for Advanced Science and Technology, University of Illinois, Urbana, Illinois
| | - Christopher E Zwilling
- Decision Neuroscience Laboratory, University of Illinois, Urbana, Illinois.,Beckman Institute for Advanced Science and Technology, University of Illinois, Urbana, Illinois
| | - Aron K Barbey
- Decision Neuroscience Laboratory, University of Illinois, Urbana, Illinois.,Beckman Institute for Advanced Science and Technology, University of Illinois, Urbana, Illinois.,Department of Psychology, University of Illinois, Urbana, Illinois.,Department of Internal Medicine, University of Illinois, Champaign, Illinois.,Department of Bioengineering, University of Illinois, Champaign, Illinois.,Carle R. Woese Institute for Genomic Biology, University of Illinois, Champaign, Illinois
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24
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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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25
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Age-Related Changes in Frontal, Striatal, and Medial Temporal Activity during Expected Value Evaluation. J Neurosci 2017; 37:3442-3444. [PMID: 28356394 DOI: 10.1523/jneurosci.0033-17.2017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Revised: 02/26/2017] [Accepted: 02/28/2017] [Indexed: 11/21/2022] Open
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26
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Yu J, Mamerow L, Lei X, Fang L, Mata R. Altered Value Coding in the Ventromedial Prefrontal Cortex in Healthy Older Adults. Front Aging Neurosci 2016; 8:210. [PMID: 27630561 PMCID: PMC5005953 DOI: 10.3389/fnagi.2016.00210] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Accepted: 08/19/2016] [Indexed: 12/01/2022] Open
Abstract
Previous work suggests that aging is associated with changes in risk taking but less is known about their underlying neural basis, such as the potential age differences in the neural processing of value and risk. The goal of the present study was to investigate adult age differences in functional neural responses in a naturalistic risk-taking task. Twenty-six young adults and 27 healthy older adults completed the Balloon Analogue Risk Task while undergoing functional magnetic resonance imaging. Young and older adults showed similar overt risk-taking behavior. Group comparison of neural activity in response to risky vs. control stimuli revealed similar patterns of activation in the bilateral striatum, anterior insula (AI) and ventromedial prefrontal cortex (vmPFC). Group comparison of parametrically modulated activity in response to continued pumping similarly revealed comparable results for both age groups in the AI and, potentially, the striatum, yet differences emerged for regional activity in the vmPFC. At whole brain level, insular, striatal and vmPFC activation was predictive of behavioral risk taking for young but not older adults. The current results are interpreted and discussed as preserved neural tracking of risk and reward in the AI and striatum, respectively, but altered value coding in the vmPFC in the two age groups. The latter finding points toward older adults exhibiting differential vmPFC-related integration and value coding. Furthermore, neural activation holds differential predictive validity for behavioral risk taking in young and older adults.
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Affiliation(s)
- Jing Yu
- Faculty of Psychology, Southwest UniversityChongqing, China; Department for Cognitive and Decision Sciences, University of BaselBasel, Switzerland; Key Laboratory of Mental Health, Institute of Psychology, Chinese Academy of SciencesBeijing, China
| | - Loreen Mamerow
- Department for Cognitive and Decision Sciences, University of Basel Basel, Switzerland
| | - Xu Lei
- Faculty of Psychology, Southwest University Chongqing, China
| | - Lei Fang
- Faculty of Medicine, Southeast University Nanjing, China
| | - Rui Mata
- Department for Cognitive and Decision Sciences, University of BaselBasel, Switzerland; Max Planck Institute for Human DevelopmentBerlin, Germany
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27
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Are there gender differences in young vs. aging brains under risk decision-making? An optical brain imaging study. Brain Imaging Behav 2016; 11:1085-1098. [DOI: 10.1007/s11682-016-9580-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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28
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Li SC, Biele G, Mohr PNC, Heekeren HR. Aging and Neuroeconomics: Insights from Research on Neuromodulation of Reward-based Decision Making. ACTA ACUST UNITED AC 2016. [DOI: 10.1515/auk-2007-0107] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
‘Neuroeconomics’ can be broadly defined as the research of how the brain interacts with the environment to make decisions that are functional given individual and contextual constraints. Deciphering such brain-environment transactions requires mechanistic understandings of the neurobiological processes that implement value-dependent decision making. To this end, a common empirical approach is to investigate neural mechanisms of reward-based decision making. Flexible updating of choices and associated expected outcomes in ways that are adaptive for a given task (or a given set of tasks) at hand relies on dynamic neurochemical tuning of the brain’s functional circuitries involved in the representation of tasks, goals and reward prediction. Empirical evidence as well as computational theories indicate that various neurotransmitter systems (e.g., dopamine, norepinephrine, and serotonin) play important roles in reward-based decision making. In light of the apparent aging-related decline in various aspects of the dopaminergic system as well as the effects of neuromodulation on reward-related processes, this article focuses selectively on the literature that highlights the triadic relations between dopaminergic modulation, reward-based decision making, and aging. Directions for future research on aging and neuroeconomoics are discussed.
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Seinstra M, Grzymek K, Kalenscher T. Gender-Specific Differences in the Relationship between Autobiographical Memory and Intertemporal Choice in Older Adults. PLoS One 2015; 10:e0137061. [PMID: 26335426 PMCID: PMC4559386 DOI: 10.1371/journal.pone.0137061] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2014] [Accepted: 08/12/2015] [Indexed: 12/13/2022] Open
Abstract
As the population of older adults grows, their economic choices will have increasing impact on society. Research on the effects of aging on intertemporal decisions shows inconsistent, often opposing results, indicating that yet unexplored factors might play an essential role in guiding one's choices. Recent studies suggest that episodic future thinking, which is based on the same neural network involved in episodic memory functions, leads to reductions in discounting of future rewards. As episodic memory functioning declines with normal aging, but to greatly variable degrees, individual differences in delay discounting might be due to individual differences in the vitality of this memory system in older adults. We investigated this hypothesis, using a sample of healthy older adults who completed an intertemporal choice task as well as two episodic memory tasks. We found no clear evidence for a relationship between episodic memory performance and delay discounting in older adults. However, when additionally considering gender differences, we found an interaction effect of gender and autobiographical memory on delay discounting: while men with higher memory scores showed less delay discounting, women with higher memory scores tended to discount the future more. We speculate that this gender effect might stem from the gender-specific use of different modal representation formats (i.e. temporal or visual) during assessment of intertemporal choice options.
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Affiliation(s)
- Maayke Seinstra
- Department of Comparative Psychology, Institute of Experimental Psychology, Heinrich-Heine University Düsseldorf, Düsseldorf, Germany
- * E-mail:
| | - Katharina Grzymek
- Department of Comparative Psychology, Institute of Experimental Psychology, Heinrich-Heine University Düsseldorf, Düsseldorf, Germany
| | - Tobias Kalenscher
- Department of Comparative Psychology, Institute of Experimental Psychology, Heinrich-Heine University Düsseldorf, Düsseldorf, Germany
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Frey R, Mata R, Hertwig R. The role of cognitive abilities in decisions from experience: Age differences emerge as a function of choice set size. Cognition 2015; 142:60-80. [PMID: 26022497 DOI: 10.1016/j.cognition.2015.05.004] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2015] [Revised: 05/04/2015] [Accepted: 05/05/2015] [Indexed: 10/23/2022]
Abstract
People seldom enjoy access to summarized information about risky options before making a decision. Instead, they may search for information and learn about environmental contingencies-thus making decisions from experience. Aging is associated with notable deficits in learning and memory-but do these translate into poorer decisions from experience? We report three studies that used a sampling paradigm to investigate younger (M=24 years) and older (M=71 years) adults' decisions from experience. In Study 1 (N=121) participants made 12 decisions between pairs of payoff distributions in the lab. Study 2 (N=70) implemented the same paradigm using portable devices, collecting 84 decisions per individual over a week. Study 3 (N=84) extended the sampling paradigm by asking participants to make 12 decisions between two, four, and eight payoff distributions (in the lab). Overall, the behavioral results suggest that younger and older adults are relatively similar in how they search and what they choose when facing two payoff distributions (Studies 1 and 2). With an increasing number of payoff distributions, however, age differences emerged (Study 3). A modeling analysis on the level of individual participants showed that a simple delta-learning rule model best described the learning processes of most participants. To the extent that ongoing updating processes unfold relatively automatically and effortlessly, older adults may be liberated from the detrimental consequences of cognitive aging in the case of decisions from experience with few decision options. We discuss implications for research on decisions from experience and choice performance over the lifespan.
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Affiliation(s)
- Renato Frey
- University of Basel, Department of Psychology, Cognitive and Decision Sciences, Missionsstrasse 64A, CH-4055 Basel, Switzerland; Max Planck Institute for Human Development, Center for Adaptive Rationality, Lentzeallee 94, DE-14195 Berlin, Germany.
| | - Rui Mata
- University of Basel, Department of Psychology, Cognitive and Decision Sciences, Missionsstrasse 64A, CH-4055 Basel, Switzerland; Max Planck Institute for Human Development, Center for Adaptive Rationality, Lentzeallee 94, DE-14195 Berlin, Germany
| | - Ralph Hertwig
- Max Planck Institute for Human Development, Center for Adaptive Rationality, Lentzeallee 94, DE-14195 Berlin, Germany
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Drueke B, Weichert L, Forkmann T, Mainz V, Gauggel S, Boecker M. Neural correlates of positive and negative performance feedback in younger and older adults. Behav Brain Funct 2015; 11:17. [PMID: 25889338 PMCID: PMC4417231 DOI: 10.1186/s12993-015-0062-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2014] [Accepted: 03/26/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Recent studies with younger adults have shown that performance feedback can serve as a reward, and it elicits reward-related brain activations. This study investigated whether performance feedback is processed similarly in younger and older adults and whether there are differential aging effects for positive and negative performance feedback. METHODS We used event-related fMRI in a choice reaction-time task and provided performance feedback after each trial. RESULTS Although younger and older adults differed in task-related activation, they showed comparable reward-related activation. Positive performance feedback elicited the strongest striatal and amygdala activation, which was reflected behaviorally in slightly faster reaction times. CONCLUSIONS These results suggest that performance feedback serves as a reward in both younger and older adults.
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Affiliation(s)
- Barbara Drueke
- Department of Medical Psychology and Medical Sociology, University Hospital of RWTH Aachen University, Pauwelsstr. 19, 52074, Aachen, Germany.
| | - Lydia Weichert
- Department of Medical Psychology and Medical Sociology, University Hospital of RWTH Aachen University, Pauwelsstr. 19, 52074, Aachen, Germany.
| | - Thomas Forkmann
- Department of Medical Psychology and Medical Sociology, University Hospital of RWTH Aachen University, Pauwelsstr. 19, 52074, Aachen, Germany.
| | - Verena Mainz
- Department of Medical Psychology and Medical Sociology, University Hospital of RWTH Aachen University, Pauwelsstr. 19, 52074, Aachen, Germany.
| | - Siegfried Gauggel
- Department of Medical Psychology and Medical Sociology, University Hospital of RWTH Aachen University, Pauwelsstr. 19, 52074, Aachen, Germany.
| | - Maren Boecker
- Department of Medical Psychology and Medical Sociology, University Hospital of RWTH Aachen University, Pauwelsstr. 19, 52074, Aachen, Germany.
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Mata R, von Helversen B. Search and the Aging Mind: The Promise and Limits of the Cognitive Control Hypothesis of Age Differences in Search. Top Cogn Sci 2015; 7:416-27. [PMID: 25820124 DOI: 10.1111/tops.12139] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2012] [Revised: 03/12/2013] [Accepted: 03/28/2013] [Indexed: 12/01/2022]
Abstract
Search is a prerequisite for successful performance in a broad range of tasks ranging from making decisions between consumer goods to memory retrieval. How does aging impact search processes in such disparate situations? Aging is associated with structural and neuromodulatory brain changes that underlie cognitive control processes, which in turn have been proposed as a domain-general mechanism controlling search in external environments as well as memory. We review the aging literature to evaluate the cognitive control hypothesis that suggests that age-related change in cognitive control underlies age differences in both external and internal search. We also consider the limits of the cognitive control hypothesis and propose additional mechanisms such as changes in strategy use and affect that may be necessary to understand how aging affects search.
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Affiliation(s)
- Rui Mata
- Department of Psychology, University of Basel
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33
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Vink M, Kleerekooper I, van den Wildenberg WPM, Kahn RS. Impact of aging on frontostriatal reward processing. Hum Brain Mapp 2015; 36:2305-17. [PMID: 25704624 DOI: 10.1002/hbm.22771] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2014] [Revised: 01/16/2015] [Accepted: 02/11/2015] [Indexed: 11/10/2022] Open
Abstract
Healthy aging is associated with a progressive decline across a range of cognitive functions. An important factor underlying this decline may be the age-related impairment in stimulus-reward processing. Several studies have investigated age-related effects, but compared young versus old subjects. This is the first study to investigate the effect of aging on brain activation during reward processing within a continuous segment of the adult life span. We scanned 49 healthy adults aged 40-70 years, using functional MRI. We adopted a simple reward task, which allowed separate evaluation of neural responses to reward anticipation and receipt. The effect of reward on performance accuracy and speed was not related to age, indicating that all subjects could perform the task correctly. We identified a whole-brain significant age-related decline of ventral striatum activation during reward anticipation as compared to neutral anticipation. Importantly, the specificity of this finding was underscored by the observation that there was no general decline in activation during anticipation. Activation in the ventral striatum increased with age during reward receipt as compared to receiving neutral outcome. Finally, activation in the ventromedial prefrontal cortex during outcome was not affected by age. Our data demonstrate that the typical shift in striatal activation from reward receipt to reward anticipation in young adults disappears with healthy aging. These changes are consistent the well-ocumented age-related decline of striatal dopamine availability, and may provide a stepping stone for further research of age-related neurodegenerative diseases.
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Affiliation(s)
- Matthijs Vink
- Brain Center Rudolf Magnus, Department of Psychiatry, University Medical Center Utrecht, Utrecht, The Netherlands
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34
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Abstract
Representation of reward value involves a distributed network including cortical and subcortical structures. Because neurodegenerative illnesses target specific anatomic networks that partially overlap with the reward circuit, they would be predicted to have distinct impairments in reward processing. This review presents the existing evidence of reward processing changes in neurodegenerative diseases including mild cognitive impairment (MCI), Alzheimer's disease, frontotemporal dementia, amyotrophic lateral sclerosis (ALS), Parkinson's disease, and Huntington's disease, as well as in healthy aging. Carefully distinguishing the different aspects of reward processing (primary rewards, secondary rewards, reward-based learning, and reward-based decision-making) and using tasks that differentiate the stages of processing reward will lead to improved understanding of this fundamental process and clarify a contributing cause of behavioral change in these illnesses.
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Affiliation(s)
- David C Perry
- a Department of Neurology , University of California , San Francisco , CA , USA
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35
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Lindbergh CA, Puente AN, Gray JC, MacKillop J, Miller LS. Discounting preferences and response consistency as markers of functional ability in community-dwelling older adults. J Clin Exp Neuropsychol 2014; 36:1112-23. [DOI: 10.1080/13803395.2014.983464] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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36
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Samson RD, Venkatesh A, Patel DH, Lipa P, Barnes CA. Enhanced performance of aged rats in contingency degradation and instrumental extinction tasks. Behav Neurosci 2014; 128:122-33. [PMID: 24773433 DOI: 10.1037/a0035986] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Normal aging in rats affects behavioral performance on a variety of associative learning tasks under Pavlovian conditions. There is little information, however, on whether aging also impacts performance of instrumental tasks. Young (9-12 months) and aged (24-27 months) Fisher 344 rats were trained to press distinct levers associated with either maltodextrin or sucrose. The rats in both age groups increased their lever press frequency at a similar rate, suggesting that the initial acquisition of this instrumental task is not affected by aging. Using a contingency degradation procedure, we then addressed whether aged rats could adapt their behavior to changes in action-outcome contingencies. We found that young and aged rats do adapt, but that a different schedule of reinforcement is necessary to optimize performance in each age group. Finally, we also addressed whether aged rats can extinguish a lever press action as well as young rats, using 2 40-min extinction sessions on consecutive days. While extinction profiles were similar in young and aged rats on the first day of training, aged rats were faster to extinguish their lever presses on the second day, in spite of their performance levels being similar at the beginning of the session. Together these data support the finding that acquisition of instrumental lever press behaviors is preserved in aged rats and suggest that they have a different threshold for switching strategies in response to changes in action-outcome associations. This pattern of result implies that age-related changes in the brain are heterogeneous and widespread across structures.
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Affiliation(s)
| | - Anu Venkatesh
- Evelyn F. McKnight Brain Institute, University of Arizona
| | - Dhara H Patel
- Evelyn F. McKnight Brain Institute, University of Arizona
| | - Peter Lipa
- Evelyn F. McKnight Brain Institute, University of Arizona
| | - Carol A Barnes
- Evelyn F. McKnight Brain Institute, University of Arizona
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Harb MR, Sousa N, Zihl J, Almeida OFX. Reward components of feeding behavior are preserved during mouse aging. Front Aging Neurosci 2014; 6:242. [PMID: 25278876 PMCID: PMC4165288 DOI: 10.3389/fnagi.2014.00242] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2014] [Accepted: 08/25/2014] [Indexed: 01/10/2023] Open
Abstract
Eating behavior depends on associations between the sensory and energetic properties of foods. Healthful balance of these factors is a challenge for industrialized societies that have an abundance of food, food choices and food-related cues. Here, we were interested in whether appetitive conditioning changes as a function of age. Operant and pavlovian conditioning experiments (rewarding stimulus was a palatable food) in male mice (aged 3, 6, and 15 months) showed that implicit (non-declarative) memory remains intact during aging. Two other essential components of eating behavior, motivation and hedonic preference for rewarding foods, were also found not to be altered in aging mice. Specifically, hedonic responding by satiated mice to isocaloric foods of differing sensory properties (sucrose, milk) was similar in all age groups; importantly, however, this paradigm disclosed that older animals adjust their energy intake according to energetic need. Based on the assumption that the mechanisms that control feeding are conserved across species, it would appear that overeating and obesity in humans reflects a mismatch between ancient physiological mechanisms and today's cue-laden environment. The implication of the present results showing that aging does not impair the ability to learn stimulus-food associations is that the risk of overeating in response to food cues is maintained through to old age.
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Affiliation(s)
- Mazen R Harb
- Max Planck Institute of Psychiatry Munich, Germany ; Portugal and ICVS/3B's-PT Government Associate Laboratory, Institute of Life and Health Sciences (ICVS), University of Minho Braga, Portugal
| | - Nuno Sousa
- Portugal and ICVS/3B's-PT Government Associate Laboratory, Institute of Life and Health Sciences (ICVS), University of Minho Braga, Portugal
| | - Joseph Zihl
- Department of Neuropsychology, Ludwig Maximilian University Munich, Germany
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Abstract
Deficient information processing with increasing age has been assigned to reduced efficiency in frontal executive control functions. Dopamine has been assumed to play a central role for this decline. Dopamine, however, is also essential for the maintenance of motivation for a longer period of time and is therefore a core factor for mental fatigue. Combining these two findings, we tested to what degree older adults are more prone to performance loss due to increasing time on task than younger adults. Twelve younger and twelve older participants performed an inhibition of return task for 80 min. Performance declined in the older participants but not in the young. Event-related potentials (ERPs) of the EEG, however, showed distinct changes with time on task primarily for young participants. The dissociation between behavioral and ERP results indicates that changes in ERPs of the young participants could reflect adaptations to the task rather than fatigue. This is evident from very distinct changes of the posterior N1 component in this group. The failing (or rather unspecific) adaptation to the task in older adults might have been a consequence of lacking frontal executive control functions reflected in a massive reduction of the N2 component of the ERP, relative to the young participants.
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Affiliation(s)
- Edmund Wascher
- Leibniz Research Centre for Working Environment and Human Factors, Dortmund, Germany
| | - Stephan Getzmann
- Leibniz Research Centre for Working Environment and Human Factors, Dortmund, Germany
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39
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Heuer H, Hegele M. Age-related variations of visuo-motor adaptation beyond explicit knowledge. Front Aging Neurosci 2014; 6:152. [PMID: 25071561 PMCID: PMC4081763 DOI: 10.3389/fnagi.2014.00152] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2013] [Accepted: 06/17/2014] [Indexed: 11/13/2022] Open
Abstract
Visuo-motor adaptation suffers at older working age. The age-related decline of behavioral adjustments is accompanied by reduced explicit knowledge of the visuo-motor transformation. It disappears when explicit knowledge is kept constant across the age range, except for particularly high levels of explicit knowledge. According to these findings, at older adult age both the acquisition of explicit knowledge and its application for strategic corrections become poorer. Recently it has been posited that visuo-motor adaptation can involve model-free reinforcement mechanisms of learning in addition to model-based mechanisms. We tested whether age-related declines of reinforcement learning can also contribute to the age-related changes of visuo-motor adaptation. Therefore we enhanced the contribution of reinforcement learning to visuo-motor adaptation by way of introducing salient markers of success and failure during practice. With such modified practice conditions, there were residual age-related variations of behavioral adjustments at all levels of explicit knowledge, even when explicit knowledge was absent. The residual age-related variations were observed for practiced target directions only, but not for new target directions. These findings are consistent with an age-related decline of model-free reinforcement learning as a third factor in the age-related decline of visuo-motor adaptation. Under practice conditions, which spur model-free reward-based learning, this factor adds to the decrements of the acquisition of explicit knowledge and its use for strategic corrections.
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Affiliation(s)
- Herbert Heuer
- Leibniz Research Centre for Working Environment and Human Factors, DortmundGermany
| | - Mathias Hegele
- Neuromotor Behavior Laboratory, Department of Sport Science, Justus-Liebig-University GiessenGiessen, Germany
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40
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Lorenz RC, Gleich T, Beck A, Pöhland L, Raufelder D, Sommer W, Rapp MA, Kühn S, Gallinat J. Reward anticipation in the adolescent and aging brain. Hum Brain Mapp 2014; 35:5153-65. [PMID: 24801222 DOI: 10.1002/hbm.22540] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2014] [Revised: 04/15/2014] [Accepted: 04/21/2014] [Indexed: 11/10/2022] Open
Abstract
Processing of reward is the basis of adaptive behavior of the human being. Neural correlates of reward processing seem to be influenced by developmental changes from adolescence to late adulthood. The aim of this study is to uncover these neural correlates during a slot machine gambling task across the lifespan. Therefore, we used functional magnetic resonance imaging to investigate 102 volunteers in three different age groups: 34 adolescents, 34 younger adults, and 34 older adults. We focused on the core reward areas ventral striatum (VS) and ventromedial prefrontal cortex (VMPFC), the valence processing associated areas, anterior cingulate cortex (ACC) and insula, as well as information integration associated areas, dorsolateral prefrontal cortex (DLPFC), and inferior parietal lobule (IPL). Results showed that VS and VMPFC were characterized by a hyperactivation in adolescents compared with younger adults. Furthermore, the ACC and insula were characterized by a U-shape pattern (hypoactivation in younger adults compared with adolescents and older adults), whereas the DLPFC and IPL were characterized by a J-shaped form (hyperactivation in older adults compared with younger groups). Furthermore, a functional connectivity analysis revealed an elevated negative functional coupling between the inhibition-related area rIFG and VS in younger adults compared with adolescents. Results indicate that lifespan-related changes during reward anticipation are characterized by different trajectories in different reward network modules and support the hypothesis of an imbalance in maturation of striatal and prefrontal cortex in adolescents. Furthermore, these results suggest compensatory age-specific effects in fronto-parietal regions.
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Affiliation(s)
- Robert C Lorenz
- Department of Psychiatry and Psychotherapy, Charité-Universitätsmedizin Berlin, Campus Mitte, Berlin, Germany; Institute of Psychology, Humboldt-Universität zu Berlin, Berlin, Germany
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41
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Developing Neurobiological Endophenotypes that Reflect Failure to Control Alcohol Consumption and Dependence. CURRENT ADDICTION REPORTS 2014. [DOI: 10.1007/s40429-013-0007-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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42
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Samson RD, Barnes CA. Impact of aging brain circuits on cognition. Eur J Neurosci 2013; 37:1903-15. [PMID: 23773059 DOI: 10.1111/ejn.12183] [Citation(s) in RCA: 114] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2012] [Revised: 02/05/2013] [Accepted: 02/11/2013] [Indexed: 01/01/2023]
Abstract
Brain networks that engage the hippocampus and prefrontal cortex are central for enabling effective interactions with our environment. Some of the cognitive processes that these structures mediate, such as encoding and retrieving episodic experience, wayfinding, working memory and attention are known to be altered across the lifespan. As illustrated by examples given below, there is remarkable consistency across species in the pattern of age-related neural and cognitive change observed in healthy humans and other animals. These include changes in cognitive operations that are known to be dependent on the hippocampus, as well as those requiring intact prefrontal cortical circuits. Certain cognitive constructs that reflect the function of these areas lend themselves to investigation across species, allowing brain mechanisms at different levels of analysis to be studied in greater depth.
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Affiliation(s)
- Rachel D Samson
- Evelyn F McKnight Brain Institute, University of Arizona, Tucson, AZ, USA
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43
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Kalapatapu RK, Lewis DF, Vinogradov S, Batki SL, Winhusen T. Relationship of age to impulsivity and decision making: a baseline secondary analysis of a behavioral treatment study in stimulant use disorders. J Addict Dis 2013; 32:206-16. [PMID: 23815427 DOI: 10.1080/10550887.2013.795471] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Because stimulant use disorders remain prevalent across the lifespan, cognition is an important area of clinical care and research focus among aging adults with stimulant use disorders. This secondary analysis of a National Institute on Drug Abuse Clinical Trials Network study suggests that decision making, verbal learning/memory, executive function, and set shifting are important cognitive domains to screen clinically and treat in aging adults with stimulant use disorders. Some suggestions are made on how clinical treatment providers can practically use these results. An important direction for future research is the development of cognitively remediating treatments for impaired cognitive domains in aging adults with stimulant use disorders.
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Affiliation(s)
- Raj K Kalapatapu
- Department of Psychiatry, University of California, San Francisco, CA, USA.
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44
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Ferdinand NK, Kray J. Age-related changes in processing positive and negative feedback: Is there a positivity effect for older adults? Biol Psychol 2013; 94:235-41. [PMID: 23886960 DOI: 10.1016/j.biopsycho.2013.07.006] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2013] [Revised: 06/10/2013] [Accepted: 07/15/2013] [Indexed: 10/26/2022]
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45
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Gould TJ, Leach PT. Cellular, molecular, and genetic substrates underlying the impact of nicotine on learning. Neurobiol Learn Mem 2013; 107:108-32. [PMID: 23973448 DOI: 10.1016/j.nlm.2013.08.004] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2013] [Revised: 08/13/2013] [Accepted: 08/13/2013] [Indexed: 12/27/2022]
Abstract
Addiction is a chronic disorder marked by long-lasting maladaptive changes in behavior and in reward system function. However, the factors that contribute to the behavioral and biological changes that occur with addiction are complex and go beyond reward. Addiction involves changes in cognitive control and the development of disruptive drug-stimuli associations that can drive behavior. A reason for the strong influence drugs of abuse can exert on cognition may be the striking overlap between the neurobiological substrates of addiction and of learning and memory, especially areas involved in declarative memory. Declarative memories are critically involved in the formation of autobiographical memories, and the ability of drugs of abuse to alter these memories could be particularly detrimental. A key structure in this memory system is the hippocampus, which is critically involved in binding multimodal stimuli together to form complex long-term memories. While all drugs of abuse can alter hippocampal function, this review focuses on nicotine. Addiction to tobacco products is insidious, with the majority of smokers wanting to quit; yet the majority of those that attempt to quit fail. Nicotine addiction is associated with the presence of drug-context and drug-cue associations that trigger drug seeking behavior and altered cognition during periods of abstinence, which contributes to relapse. This suggests that understanding the effects of nicotine on learning and memory will advance understanding and potentially facilitate treating nicotine addiction. The following sections examine: (1) how the effects of nicotine on hippocampus-dependent learning change as nicotine administration transitions from acute to chronic and then to withdrawal from chronic treatment and the potential impact of these changes on addiction, (2) how nicotine usurps the cellular mechanisms of synaptic plasticity, (3) the physiological changes in the hippocampus that may contribute to nicotine withdrawal deficits in learning, and (4) the role of genetics and developmental stage (i.e., adolescence) in these effects.
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Affiliation(s)
- Thomas J Gould
- Temple University Department of Psychology, Neuroscience Program, Temple University, Philadelphia, PA 19122, United States.
| | - Prescott T Leach
- Temple University Department of Psychology, Neuroscience Program, Temple University, Philadelphia, PA 19122, United States
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46
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Money for nothing - Atrophy correlates of gambling decision making in behavioural variant frontotemporal dementia and Alzheimer's disease. NEUROIMAGE-CLINICAL 2013; 2:263-72. [PMID: 24179781 PMCID: PMC3778267 DOI: 10.1016/j.nicl.2013.01.011] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/13/2012] [Revised: 01/15/2013] [Accepted: 01/28/2013] [Indexed: 11/23/2022]
Abstract
Neurodegenerative patients show often severe everyday decision making problems. Currently it is however not clear which brain atrophy regions are implicated in such decision making problems. We investigated the atrophy correlates of gambling decision making in a sample of 63 participants, including two neurodegenerative conditions (behavioural variant frontotemporal dementia — bvFTD; Alzheimer's disease — AD) as well as healthy age-matched controls. All participants were tested on the Iowa Gambling Task (IGT) and the behavioural IGT results were covaried against the T1 MRI scans of all participants to identify brain atrophy regions implicated in gambling decision making deficits. Our results showed a large variability in IGT performance for all groups with both patient groups performing especially poor on the task. Importantly, bvFTD and AD groups did not differ significantly on the behavioural performance of the IGT. However, by contrast, the atrophy gambling decision making correlates differed between bvFTD and AD, with bvFTD showing more frontal atrophy and AD showing more parietal and temporal atrophy being implicated in decision making deficits, indicating that both patient groups fail the task on different levels. Frontal (frontopolar, anterior cingulate) and parietal (retrosplenial) cortex atrophy covaried with poor performance on the IGT. Taken together, the atrophy correlates of gambling decision making show that such deficits can occur due to a failure of different neural structures, which will inform future diagnostics and treatment options to alleviate these severe everyday problems in neurodegenerative patients.
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Abstract
Activation of the hippocampus is required to encode memories for new events (or episodes). Observations from animal studies suggest that, for these memories to persist beyond 4-6 h, a release of dopamine generated by strong hippocampal activation is needed. This predicts that dopaminergic enhancement should improve human episodic memory persistence also for events encoded with weak hippocampal activation. Here, using pharmacological functional MRI (fMRI) in an elderly population in which there is a loss of dopamine neurons as part of normal aging, we show this very effect. The dopamine precursor levodopa led to a dose-dependent (inverted U-shape) persistent episodic memory benefit for images of scenes when tested after 6 h, independent of whether encoding-related hippocampal fMRI activity was weak or strong (U-shaped dose-response relationship). This lasting improvement even for weakly encoded events supports a role for dopamine in human episodic memory consolidation, albeit operating within a narrow dose range.
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de Boer A, Ter Horst GJ, Lorist MM. Physiological and psychosocial age-related changes associated with reduced food intake in older persons. Ageing Res Rev 2013; 12:316-28. [PMID: 22974653 DOI: 10.1016/j.arr.2012.08.002] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2012] [Revised: 08/02/2012] [Accepted: 08/29/2012] [Indexed: 01/23/2023]
Abstract
Dietary intake changes during the course of aging. Normally an increase in food intake is observed around 55 years of age, which is followed by a reduction in food intake in individuals over 65 years of age. This reduction in dietary intake results in lowered levels of body fat and body weight, a phenomenon known as anorexia of aging. Anorexia of aging has a variety of consequences, including a decline in functional status, impaired muscle function, decreased bone mass, micronutrient deficiencies, reduced cognitive functions, increased hospital admission and even premature death. Several changes during lifetime have been implicated to play a role in the reduction in food intake and the development of anorexia of aging. These changes are both physiological, involving peripheral hormones, senses and central brain regulation and non-physiological, with differences in psychological and social factors. In the present review, we will focus on age-related changes in physiological and especially non-physiological factors, that play a role in the age-related changes in food intake and in the etiology of anorexia of aging. At the end we conclude with suggestions for future nutritional research to gain greater understanding of the development of anorexia of aging which could lead to earlier detection and better prevention.
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McCarrey AC, Henry JD, von Hippel W, Weidemann G, Sachdev PS, Wohl MJA, Williams M. Age differences in neural activity during slot machine gambling: an fMRI study. PLoS One 2012; 7:e49787. [PMID: 23209599 PMCID: PMC3509121 DOI: 10.1371/journal.pone.0049787] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2012] [Accepted: 10/11/2012] [Indexed: 11/18/2022] Open
Abstract
This study aimed to assess the potential association between age-related prefrontal brain changes and slot machine gambling, an activity that has become increasingly popular among older adults. Functional magnetic resonance imaging was used to assess healthy older and younger adults whilst playing a slot machine. Results revealed that the older group over-recruited several bilateral and contralateral brain structures relative to the younger group. Specifically, older adults exhibited increased neural activation in the superior prefrontal cortex and left orbitofrontal cortex, indicating greater reliance on these structures. These results suggest a compensatory mechanism, by which older adults recruit a greater number of neural networks from both hemispheres to complete the same gambling task as their younger peers. The broader implications of these findings are discussed in relation to theories of neurocognitive and degenerative change that occurs in late adulthood.
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Affiliation(s)
- Anna C. McCarrey
- Department of Clinical Neurosciences, Cambridge University and Medical Research Council Cognition and Brain Sciences Unit, Cambridge, United Kingdom
| | - Julie D. Henry
- School of Psychology, University of Queensland, St Lucia, Queensland, Australia
- * E-mail:
| | - William von Hippel
- School of Psychology, University of Queensland, St Lucia, Queensland, Australia
| | | | - Perminder S. Sachdev
- Brain and Ageing Research Program, School of Psychiatry, University of New South Wales, Sydney, Australia
- Neuropsychiatric Institute, Prince of Wales Hospital, Sydney, Australia
| | | | - Mark Williams
- Macquarie Centre for Cognitive Science, Macquarie University, Sydney, Australia
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50
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Willingness to wait and altered encoding of time-discounted reward in the orbitofrontal cortex with normal aging. J Neurosci 2012; 32:5525-33. [PMID: 22514314 DOI: 10.1523/jneurosci.0586-12.2012] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Normal aging has been associated with cognitive changes, including shifts in responding for time-discounted rewards. The orbitofrontal cortex, an area previously associated with aging-related cognitive changes, is critical for normal discounting. Previously we have shown in a choice task that rats prefer immediate over delayed reward and that neural representations of delayed reward in orbitofrontal cortex were attenuated, whereas immediate reward elicited strong responses. Changes in choice performance were correlated with changes in firing rate in orbitofrontal neurons, suggesting that these reward representations were critical to the rats' ability to wait for reward. Here we asked whether age-dependent changes in discounting behavior were related to changes in the representation of delayed reward in the orbitofrontal cortex. Young (3-6 months) and aged (22-26 months) rats were trained on the same discounting paradigm used previously. We found that aged rats showed less sensitivity to increasing delay preceding reward delivery, shifting behavior away from the delayed reward more slowly than younger rats. This sensitivity was specific to delay, since choice performance did not differ between the two groups when delay was held constant and reward size varied. Aged rats exhibited a corresponding increase in the prevalence of neurons that fired more strongly for delayed reward. Again this change was specific to delay; there was no change in encoding of different-sized rewards. These results suggest that natural aging results in altered representations of reward in orbitofrontal cortex. These changes may relate to the increased ability to delay gratification and reduced impulsivity associated with aging.
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