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Pérez-Cervera L, De Santis S, Marcos E, Ghorbanzad-Ghaziany Z, Trouvé-Carpena A, Selim MK, Pérez-Ramírez Ú, Pfarr S, Bach P, Halli P, Kiefer F, Moratal D, Kirsch P, Sommer WH, Canals S. Alcohol-induced damage to the fimbria/fornix reduces hippocampal-prefrontal cortex connection during early abstinence. Acta Neuropathol Commun 2023; 11:101. [PMID: 37344865 PMCID: PMC10286362 DOI: 10.1186/s40478-023-01597-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Accepted: 05/30/2023] [Indexed: 06/23/2023] Open
Abstract
INTRODUCTION Alcohol dependence is characterized by a gradual reduction in cognitive control and inflexibility to contingency changes. The neuroadaptations underlying this aberrant behavior are poorly understood. Using an animal model of alcohol use disorders (AUD) and complementing diffusion-weighted (dw)-MRI with quantitative immunohistochemistry and electrophysiological recordings, we provide causal evidence that chronic intermittent alcohol exposure affects the microstructural integrity of the fimbria/fornix, decreasing myelin basic protein content, and reducing the effective communication from the hippocampus (HC) to the prefrontal cortex (PFC). Using a simple quantitative neural network model, we show how disturbed HC-PFC communication may impede the extinction of maladaptive memories, decreasing flexibility. Finally, combining dw-MRI and psychometric data in AUD patients, we discovered an association between the magnitude of microstructural alteration in the fimbria/fornix and the reduction in cognitive flexibility. Overall, these findings highlight the vulnerability of the fimbria/fornix microstructure in AUD and its potential contribution to alcohol pathophysiology. Fimbria vulnerability to alcohol underlies hippocampal-prefrontal cortex dysfunction and correlates with cognitive impairment.
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Affiliation(s)
- Laura Pérez-Cervera
- Instituto de Neurociencias, Consejo Superior de Investigaciones Científicas and Universidad Miguel Hernández, Sant Joan d'Alacant, Alicante, Spain
| | - Silvia De Santis
- Instituto de Neurociencias, Consejo Superior de Investigaciones Científicas and Universidad Miguel Hernández, Sant Joan d'Alacant, Alicante, Spain
| | - Encarni Marcos
- Instituto de Neurociencias, Consejo Superior de Investigaciones Científicas and Universidad Miguel Hernández, Sant Joan d'Alacant, Alicante, Spain
| | - Zahra Ghorbanzad-Ghaziany
- Instituto de Neurociencias, Consejo Superior de Investigaciones Científicas and Universidad Miguel Hernández, Sant Joan d'Alacant, Alicante, Spain
- Radiation Science and Biomedical Imaging, University of Sherbrooke, Sherbrooke, Québec, Canada
| | - Alejandro Trouvé-Carpena
- Instituto de Neurociencias, Consejo Superior de Investigaciones Científicas and Universidad Miguel Hernández, Sant Joan d'Alacant, Alicante, Spain
| | - Mohamed Kotb Selim
- Instituto de Neurociencias, Consejo Superior de Investigaciones Científicas and Universidad Miguel Hernández, Sant Joan d'Alacant, Alicante, Spain
| | - Úrsula Pérez-Ramírez
- Center for Biomaterials and Tissue Engineering, Universitat Politècnica de València, Valencia, Spain
| | - Simone Pfarr
- Institute of Psychopharmacology, Central Institute of Mental Health, Medical faculty Mannheim, University of Heidelberg, Mannheim, Germany
| | - Patrick Bach
- Department of Addiction Medicine, Department of Clinical Psychology, Medical Faculty Mannheim, Central Institute of Mental Health, University of Heidelberg, Mannheim, Germany
| | - Patrick Halli
- Department of Psychology, University of Heidelberg, Heidelberg, Germany
| | - Falk Kiefer
- Department of Addiction Medicine, Department of Clinical Psychology, Medical Faculty Mannheim, Central Institute of Mental Health, University of Heidelberg, Mannheim, Germany
| | - David Moratal
- Center for Biomaterials and Tissue Engineering, Universitat Politècnica de València, Valencia, Spain
| | - Peter Kirsch
- Department of Psychology, University of Heidelberg, Heidelberg, Germany
| | - Wolfgang H Sommer
- Institute of Psychopharmacology, Central Institute of Mental Health, Medical faculty Mannheim, University of Heidelberg, Mannheim, Germany.
- Department of Addiction Medicine, Department of Clinical Psychology, Medical Faculty Mannheim, Central Institute of Mental Health, University of Heidelberg, Mannheim, Germany.
| | - Santiago Canals
- Instituto de Neurociencias, Consejo Superior de Investigaciones Científicas and Universidad Miguel Hernández, Sant Joan d'Alacant, Alicante, Spain.
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Aghjayan SL, Lesnovskaya A, Esteban-Cornejo I, Peven JC, Stillman CM, Erickson KI. Aerobic exercise, cardiorespiratory fitness, and the human hippocampus. Hippocampus 2021; 31:817-844. [PMID: 34101305 PMCID: PMC8295234 DOI: 10.1002/hipo.23337] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Revised: 04/22/2021] [Accepted: 04/25/2021] [Indexed: 01/27/2023]
Abstract
The hippocampus is particularly susceptible to neurodegeneration. Physical activity, specifically increasing cardiorespiratory fitness via aerobic exercise, shows promise as a potential method for mitigating hippocampal decline in humans. Numerous studies have now investigated associations between the structure and function of the hippocampus and engagement in physical activity. Still, there remains continued debate and confusion about the relationship between physical activity and the human hippocampus. In this review, we describe the current state of the physical activity and exercise literature as it pertains to the structure and function of the human hippocampus, focusing on four magnetic resonance imaging measures: volume, diffusion tensor imaging, resting-state functional connectivity, and perfusion. We conclude that, despite significant heterogeneity in study methods, populations of interest, and scope, there are consistent positive findings, suggesting a promising role for physical activity in promoting hippocampal structure and function throughout the lifespan.
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Affiliation(s)
- Sarah L Aghjayan
- Department of Psychology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.,Center for the Neural Basis of Cognition, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Alina Lesnovskaya
- Department of Psychology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.,Center for the Neural Basis of Cognition, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Irene Esteban-Cornejo
- PROFITH "PROmoting FITness and Health Through Physical Activity" Research Group, Sport and Health University Research Institute (iMUDS), Department of Physical Education and Sports, Faculty of Sport Sciences, University of Granada, Granada, Spain.,College of Science, Health, Engineering, and Education, Murdoch University, Perth, Western Australia
| | - Jamie C Peven
- Department of Psychology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.,Center for the Neural Basis of Cognition, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Chelsea M Stillman
- Department of Psychology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA
| | - Kirk I Erickson
- Department of Psychology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.,Center for the Neural Basis of Cognition, University of Pittsburgh, Pittsburgh, Pennsylvania, USA.,College of Science, Health, Engineering, and Education, Murdoch University, Perth, Western Australia
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Pelekanos V, Premereur E, Mitchell DJ, Chakraborty S, Mason S, Lee ACH, Mitchell AS. Corticocortical and Thalamocortical Changes in Functional Connectivity and White Matter Structural Integrity after Reward-Guided Learning of Visuospatial Discriminations in Rhesus Monkeys. J Neurosci 2020; 40:7887-7901. [PMID: 32900835 PMCID: PMC7548693 DOI: 10.1523/jneurosci.0364-20.2020] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Revised: 06/30/2020] [Accepted: 07/25/2020] [Indexed: 12/14/2022] Open
Abstract
The frontal cortex and temporal lobes together regulate complex learning and memory capabilities. Here, we collected resting-state functional and diffusion-weighted MRI data before and after male rhesus macaque monkeys received extensive training to learn novel visuospatial discriminations (reward-guided learning). We found functional connectivity changes in orbitofrontal, ventromedial prefrontal, inferotemporal, entorhinal, retrosplenial, and anterior cingulate cortices, the subicular complex, and the dorsal, medial thalamus. These corticocortical and thalamocortical changes in functional connectivity were accompanied by related white matter structural alterations in the uncinate fasciculus, fornix, and ventral prefrontal tract: tracts that connect (sub)cortical networks and are implicated in learning and memory processes in monkeys and humans. After the well-trained monkeys received fornix transection, they were impaired in learning new visuospatial discriminations. In addition, the functional connectivity profile that was observed after the training was altered. These changes were accompanied by white matter changes in the ventral prefrontal tract, although the integrity of the uncinate fasciculus remained unchanged. Our experiments highlight the importance of different communication relayed among corticocortical and thalamocortical circuitry for the ability to learn new visuospatial associations (learning-to-learn) and to make reward-guided decisions.SIGNIFICANCE STATEMENT Frontal neural networks and the temporal lobes contribute to reward-guided learning in mammals. Here, we provide novel insight by showing that specific corticocortical and thalamocortical functional connectivity is altered after rhesus monkeys received extensive training to learn novel visuospatial discriminations. Contiguous white matter fiber pathways linking these gray matter structures, namely, the uncinate fasciculus, fornix, and ventral prefrontal tract, showed structural changes after completing training in the visuospatial task. Additionally, different patterns of functional and structural connectivity are reported after removal of subcortical connections within the extended hippocampal system, via fornix transection. These results highlight the importance of both corticocortical and thalamocortical interactions in reward-guided learning in the normal brain and identify brain structures important for memory capabilities after injury.
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Affiliation(s)
- Vassilis Pelekanos
- Department of Experimental Psychology, University of Oxford, Oxford OX1 3SR, United Kingdom
| | - Elsie Premereur
- Laboratory for Neuro- and Psychophysiology, KU Leuven, 3000 Leuven, Belgium
| | - Daniel J Mitchell
- MRC Cognition and Brain Sciences Unit, University of Cambridge, Cambridge CB2 7EF, United Kingdom
| | - Subhojit Chakraborty
- Department of Neuroinflammation, Queen Square Multiple Sclerosis Centre, Institute of Neurology, University College London, London WC1N 3BG, United Kingdom
| | - Stuart Mason
- Department of Experimental Psychology, University of Oxford, Oxford OX1 3SR, United Kingdom
| | - Andy C H Lee
- Department of Psychology (Scarborough), University of Toronto, Toronto, Ontario M1C 1A4, Canada
- Rotman Research Institute, Baycrest Centre, Toronto, Ontario M6A 2E1, Canada
| | - Anna S Mitchell
- Department of Experimental Psychology, University of Oxford, Oxford OX1 3SR, United Kingdom
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Nonhuman primate models of hippocampal development and dysfunction. Proc Natl Acad Sci U S A 2019; 116:26210-26216. [PMID: 31871159 DOI: 10.1073/pnas.1902278116] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Nonhuman primates provide highly valuable animal models that have significantly advanced our understanding of numerous behavioral and biological phenomena in humans. Here, we reviewed a series of developmental neuropsychological studies that informed us on the timing of development of the hippocampus and of hippocampal-dependent cognitive functions in primates. Data indicate that, in primates, the emergence of adult-like proficiency on behavioral tasks sensitive to hippocampal dysfunction is a stepwise process and reflects the gradual maturation of different hippocampal circuits and their connections with other neural structures. Profound and persistent memory loss resulting from insult to the hippocampus in infancy was absent in early infancy but became evident later in childhood and persisted in adulthood, indicating very little sparing or recovery of function. Finally, the early hippocampal insult resulted in both adaptive and maladaptive neuroplasticity: i.e., sparing contextual memory, but affecting working memory processes as well as emotional reactivity and hypothalamic-pituitary-adrenal (HPA) axis functioning. The results provide significant information on the emergence of hippocampal-dependent functions in humans, on the time course of memory impairment in human cases with early hippocampal insult, and on the clinical implication of the hippocampus in developmental neuropsychiatric disorders.
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Kochunov P, Huang J, Chen S, Li Y, Tan S, Fan F, Feng W, Wang Y, Rowland LM, Savransky A, Du X, Chiappelli J, Chen S, Jahanshad N, Thompson PM, Ryan MC, Adhikari B, Sampath H, Cui Y, Wang Z, Yang F, Tan Y, Hong LE. White Matter in Schizophrenia Treatment Resistance. Am J Psychiatry 2019; 176:829-838. [PMID: 31352812 PMCID: PMC6773514 DOI: 10.1176/appi.ajp.2019.18101212] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
OBJECTIVE Failure of antipsychotic medications to resolve symptoms in patients with schizophrenia creates a clinical challenge that is known as treatment resistance. The causes of treatment resistance are unknown, but it is associated with earlier age at onset and more severe cognitive deficits. The authors tested the hypothesis that white matter deficits that are involved in both neurodevelopment and severity of cognitive deficits in schizophrenia are associated with a higher risk of treatment resistance. METHODS The study sample (N=122; mean age, 38.2 years) included schizophrenia patients at treatment initiation (N=45), patients whose symptoms were treatment responsive (N=40), and patients whose symptoms were treatment resistant (N=37), as well as healthy control subjects (N=78; mean age, 39.2 years). White matter regional vulnerability index (RVI) was tested as a predictor of treatment resistance and cognitive deficits. Higher RVI is indicative of better agreement between diffusion tensor imaging fractional anisotropy across the brain in an individual and the pattern identified by the largest-to-date meta-analysis of white matter deficits in schizophrenia. RESULTS Patients with treatment-resistant symptoms showed the highest white matter RVI (mean=0.38 [SD=0.2]), which was significantly higher than the RVI among patients with treatment-responsive symptoms (mean=0.30 [SD=0.02]). At the onset of treatment, schizophrenia patients showed significantly higher RVI than healthy control subjects (mean=0.18 [SD=0.03] and mean=0.13 [SD=0.02], respectively). RVIs were significantly correlated with performance on processing speed and negative symptoms. CONCLUSIONS Schizophrenia affects white matter microstructure in specific regional patterns. Susceptibility to white matter regional deficits is associated with an increased likelihood of treatment resistance. Developments to overcome schizophrenia treatment resistance should consider white matter as an important target.
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Affiliation(s)
- Peter Kochunov
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD, USA,Corresponding Authors: Dr. Kochunov (), Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD, USA, Phone: (410) 402-6110, Fax: (410) 402-6778; Dr. Tan (), Beijing Huilongguan Hospital, Peking University, Huilongguan Clinical Medical School, Beijing, P. R. China, Phone: (800) 010-83024532, Fax: (800) 010-83020156
| | - Junchao Huang
- Beijing Huilongguan Hospital, Peking University Huilongguan Clinical Medical School, Beijing, P. R. China
| | - Song Chen
- Beijing Huilongguan Hospital, Peking University Huilongguan Clinical Medical School, Beijing, P. R. China
| | - Yanli Li
- Beijing Huilongguan Hospital, Peking University Huilongguan Clinical Medical School, Beijing, P. R. China
| | - Shuping Tan
- Beijing Huilongguan Hospital, Peking University Huilongguan Clinical Medical School, Beijing, P. R. China
| | - Fengmei Fan
- Beijing Huilongguan Hospital, Peking University Huilongguan Clinical Medical School, Beijing, P. R. China
| | - Wei Feng
- Beijing Huilongguan Hospital, Peking University Huilongguan Clinical Medical School, Beijing, P. R. China
| | - Yunhui Wang
- Beijing Huilongguan Hospital, Peking University Huilongguan Clinical Medical School, Beijing, P. R. China
| | - Laura M. Rowland
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Anya Savransky
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Xiaoming Du
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Joshua Chiappelli
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Shuo Chen
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Neda Jahanshad
- Imaging Genetics Center, Stevens Institute for Neuroimaging & Informatics, Keck School of Medicine of USC, Marina del Rey, CA, USA
| | - Paul M. Thompson
- Imaging Genetics Center, Stevens Institute for Neuroimaging & Informatics, Keck School of Medicine of USC, Marina del Rey, CA, USA
| | - Meghann C. Ryan
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Bhim Adhikari
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Hemalatha Sampath
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD, USA
| | - Yimin Cui
- Department of Pharmacy, Peking University First Hospital, Beijing, P.R. China
| | - Zhiren Wang
- Beijing Huilongguan Hospital, Peking University Huilongguan Clinical Medical School, Beijing, P. R. China
| | - Fude Yang
- Beijing Huilongguan Hospital, Peking University Huilongguan Clinical Medical School, Beijing, P. R. China
| | - Yunlong Tan
- Beijing Huilongguan Hospital, Peking University Huilongguan Clinical Medical School, Beijing, P. R. China,Corresponding Authors: Dr. Kochunov (), Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD, USA, Phone: (410) 402-6110, Fax: (410) 402-6778; Dr. Tan (), Beijing Huilongguan Hospital, Peking University, Huilongguan Clinical Medical School, Beijing, P. R. China, Phone: (800) 010-83024532, Fax: (800) 010-83020156
| | - L. Elliot Hong
- Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD, USA
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Hodgetts CJ, Postans M, Warne N, Varnava A, Lawrence AD, Graham KS. Distinct contributions of the fornix and inferior longitudinal fasciculus to episodic and semantic autobiographical memory. Cortex 2017; 94:1-14. [PMID: 28710907 PMCID: PMC5576916 DOI: 10.1016/j.cortex.2017.05.010] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Revised: 03/30/2017] [Accepted: 05/12/2017] [Indexed: 11/01/2022]
Abstract
Autobiographical memory (AM) is multifaceted, incorporating the vivid retrieval of contextual detail (episodic AM), together with semantic knowledge that infuses meaning and coherence into past events (semantic AM). While neuropsychological evidence highlights a role for the hippocampus and anterior temporal lobe (ATL) in episodic and semantic AM, respectively, it is unclear whether these constitute dissociable large-scale AM networks. We used high angular resolution diffusion-weighted imaging and constrained spherical deconvolution-based tractography to assess white matter microstructure in 27 healthy young adult participants who were asked to recall past experiences using word cues. Inter-individual variation in the microstructure of the fornix (the main hippocampal input/output pathway) related to the amount of episodic, but not semantic, detail in AMs - independent of memory age. Conversely, microstructure of the inferior longitudinal fasciculus, linking occipitotemporal regions with ATL, correlated with semantic, but not episodic, AMs. Further, these significant correlations remained when controlling for hippocampal and ATL grey matter volume, respectively. This striking correlational double dissociation supports the view that distinct, large-scale distributed brain circuits underpin context and concepts in AM.
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Affiliation(s)
- Carl J Hodgetts
- Cardiff University Brain Research Imaging Centre, School of Psychology, Cardiff University, Cardiff, Wales, UK.
| | - Mark Postans
- Cardiff University Brain Research Imaging Centre, School of Psychology, Cardiff University, Cardiff, Wales, UK; BRAIN Unit, Cardiff University, Cardiff, Wales, UK
| | - Naomi Warne
- MRC Centre for Neuropsychiatric Genetics and Genomics, Division of Psychological Medicine and Clinical Neurosciences, School of Medicine, Cardiff University, Cardiff, Wales, UK
| | - Alice Varnava
- Cardiff University Brain Research Imaging Centre, School of Psychology, Cardiff University, Cardiff, Wales, UK
| | - Andrew D Lawrence
- Cardiff University Brain Research Imaging Centre, School of Psychology, Cardiff University, Cardiff, Wales, UK
| | - Kim S Graham
- Cardiff University Brain Research Imaging Centre, School of Psychology, Cardiff University, Cardiff, Wales, UK
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7
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Henson RN, Greve A, Cooper E, Gregori M, Simons JS, Geerligs L, Erzinçlioğlu S, Kapur N, Browne G. The effects of hippocampal lesions on MRI measures of structural and functional connectivity. Hippocampus 2016; 26:1447-1463. [PMID: 27479794 PMCID: PMC5082505 DOI: 10.1002/hipo.22621] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Revised: 07/06/2016] [Accepted: 07/27/2016] [Indexed: 11/09/2022]
Abstract
Focal lesions can affect connectivity between distal brain regions (connectional diaschisis) and impact the graph-theoretic properties of major brain networks (connectomic diaschisis). Given its unique anatomy and diverse range of functions, the hippocampus has been claimed to be a critical "hub" in brain networks. We investigated the effects of hippocampal lesions on structural and functional connectivity in six patients with amnesia, using a range of magnetic resonance imaging (MRI) analyses. Neuropsychological assessment revealed marked episodic memory impairment and generally intact performance across other cognitive domains. The hippocampus was the only brain structure exhibiting reduced grey-matter volume that was consistent across patients, and the fornix was the only major white-matter tract to show altered structural connectivity according to both diffusion metrics. Nonetheless, functional MRI revealed both increases and decreases in functional connectivity. Analysis at the level of regions within the default-mode network revealed reduced functional connectivity, including between nonhippocampal regions (connectional diaschisis). Analysis at the level of functional networks revealed reduced connectivity between thalamic and precuneus networks, but increased connectivity between the default-mode network and frontal executive network. The overall functional connectome showed evidence of increased functional segregation in patients (connectomic diaschisis). Together, these results point to dynamic reorganization following hippocampal lesions, with both decreased and increased functional connectivity involving limbic-diencephalic structures and larger-scale networks. © 2016 The Authors Hippocampus Published by Wiley Periodicals, Inc.
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Affiliation(s)
| | - Andrea Greve
- MRC Cognition & Brain Sciences Unit, Cambridge, England
| | - Elisa Cooper
- MRC Cognition & Brain Sciences Unit, Cambridge, England
| | - Mariella Gregori
- Neuropsychology Department, Addenbrooke's Hospital, Cambridge University Hospitals NHS Foundation Trust, Cambridge, England
| | - Jon S Simons
- Department of Psychology, University of Cambridge, Cambridge, United Kingdom
| | | | | | - Narinder Kapur
- Research Department of Clinical, Educational and Health Psychology, University College London, London, United Kingdom
| | - Georgina Browne
- Neuropsychology Department, Addenbrooke's Hospital, Cambridge University Hospitals NHS Foundation Trust, Cambridge, England
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Meng Y, Hu X, Bachevalier J, Zhang X. Decreased functional connectivity in dorsolateral prefrontal cortical networks in adult macaques with neonatal hippocampal lesions: Relations to visual working memory deficits. Neurobiol Learn Mem 2016; 134 Pt A:31-37. [PMID: 27063864 DOI: 10.1016/j.nlm.2016.04.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2015] [Revised: 03/17/2016] [Accepted: 04/06/2016] [Indexed: 01/20/2023]
Abstract
Neonatal hippocampal lesions in monkeys impairs normal performance on both relational and working memory tasks, suggesting that the early lesions have impacted the normal development of prefrontal-hippocampal functional interactions necessary for normal performance on these tasks. Given that working memory processes engage distributed neuronal networks associated with the prefrontal cortex, it is critical to explore the integrity of distributed neural networks of dorsolateral prefrontal cortex (dlPFC) following neonatal hippocampal lesions in monkeys. We used resting-state functional MRI to assess functional connectivity of dlPFC networks in monkeys with neonatal neurotoxic hippocampal lesion (Neo-Hibo, n=4) and sham-operated control animals (Neo-C, n=4). Significant differences in the patterns of dlPFC functional networks were found between Groups Neo-Hibo and Neo-C. The within-group maps and the between-group comparisons yielded a highly coherent picture showing altered interactions of core regions of the working memory network (medial prefrontal cortex and posterior parietal cortex) as well as the dorsal (fundus of superior temporal area and superior temporal cortex) and ventral (V4 and infero-temporal cortex) visual processing areas in animals with Neo-Hibo lesions. Correlations between functional connectivity changes and working memory impairment in the same animals were found only between the dlPFC and visual cortical areas (V4 and infero-temporal cortex). Thus, the impact of the neonatal hippocampal lesions extends to multiple cortical areas interconnected with the dlPFC.
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Affiliation(s)
- Yuguang Meng
- Yerkes Imaging Center, Yerkes National Primate Research Center, Emory University, Atlanta, GA, USA
| | - Xiaoping Hu
- Coulter Department of Biomedical Engineering, Emory University and Georgia Institute of Technology, Atlanta, GA, USA
| | - Jocelyne Bachevalier
- Yerkes National Primate Research Center and Department of Psychology, Emory University, Atlanta, GA, USA.
| | - Xiaodong Zhang
- Yerkes Imaging Center, Yerkes National Primate Research Center, Emory University, Atlanta, GA, USA; Division of Neuropharmacology and Neurologic Diseases, Yerkes National Primate Research Center, Emory University, Atlanta, GA, USA.
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Ghoshal A, Conn PJ. The hippocampo-prefrontal pathway: a possible therapeutic target for negative and cognitive symptoms of schizophrenia. FUTURE NEUROLOGY 2015; 10:115-128. [PMID: 25825588 DOI: 10.2217/fnl.14.63] [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] [Indexed: 01/09/2023]
Abstract
The hippocampo-prefrontal (H-PFC) pathway has been linked to cognitive and emotional disturbances in several psychiatric disorders including schizophrenia. Preclinical evidence from the NMDA receptor antagonism rodent model of schizophrenia shows severe pathology selective to the H-PFC pathway. It is speculated that there is an increased excitatory drive from the hippocampus to the prefrontal cortex due to dysfunctions in the H-PFC plasticity, which may serve as the basis for the behavioral consequences observed in this rodent model. Thus, the H-PFC pathway is currently emerging as a promising therapeutic target for the negative and cognitive symptom clusters of schizophrenia. Here, we have reviewed the physiological, pharmacological and functional characteristics of the H-PFC pathway and we propose that allosteric activation of glutamatergic and cholinergic neurotransmission can serve as a plausible therapeutic approach.
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Affiliation(s)
- Ayan Ghoshal
- Vanderbilt Center for Neuroscience Drug Discovery, Department of Pharmacology, Vanderbilt University Medical Center, Nashville, TN 37232 0697, USA
| | - P Jeffrey Conn
- Vanderbilt Center for Neuroscience Drug Discovery, Department of Pharmacology, Vanderbilt University Medical Center, Nashville, TN 37232 0697, USA
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10
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Meng Y, Payne C, Li L, Hu X, Zhang X, Bachevalier J. Alterations of hippocampal projections in adult macaques with neonatal hippocampal lesions: a Diffusion Tensor Imaging study. Neuroimage 2014; 102 Pt 2:828-37. [PMID: 25204865 DOI: 10.1016/j.neuroimage.2014.08.059] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2014] [Revised: 08/27/2014] [Accepted: 08/31/2014] [Indexed: 11/26/2022] Open
Abstract
Neuropsychological and brain imaging studies have demonstrated persistent deficits in memory functions and structural changes after neonatal neurotoxic hippocampal lesion in monkeys. However, the relevant microstructural changes in the white matter of affected brain regions following this early insult remain unknown. This study assessed white matter integrity in the main hippocampal projections of adult macaque monkeys with neonatal hippocampal lesions, using diffusion tensor imaging (DTI). Data analysis was performed using tract-based spatial statistics (TBSS) and compared with volume of interest statistics. Alterations of fractional anisotropy (FA) and diffusivity indices were observed in fornix, temporal stem, ventromedial prefrontal cortex and optical radiations. To further validate the lesion effects on the prefrontal cortex, probabilistic diffusion tractography was used to examine the integrity of the fiber connections between hippocampus and ventromedial prefrontal cortex, and alterations were found in these connections. In addition, increased radial diffusivity in the left ventromedial prefrontal cortex correlated negatively with the severity of deficits in working memory in the same monkeys. The findings revealed microstructural changes due to neonatal hippocampal lesion, and confirmed that neonatal neurotoxic hippocampal lesions resulted in significant and enduring functional alterations in the hippocampal projection system.
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Affiliation(s)
- Yuguang Meng
- Yerkes Imaging Center, Yerkes National Primate Research Center, Emory University, Atlanta, GA, USA
| | - Christa Payne
- Yerkes National Primate Research Center, Emory University, Atlanta, GA, USA; Department of Psychology, Emory University, Atlanta, GA, USA
| | - Longchuan Li
- Marcus Autism Center, Children's Healthcare of Atlanta, Emory University, Atlanta, GA, USA
| | - Xiaoping Hu
- Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, GA 30322, USA
| | - Xiaodong Zhang
- Yerkes Imaging Center, Yerkes National Primate Research Center, Emory University, Atlanta, GA, USA; Division of Neuropharmacology and Neurologic Diseases, Yerkes National Primate Research Center, Emory University, Atlanta, GA, USA.
| | - Jocelyne Bachevalier
- Yerkes National Primate Research Center, Emory University, Atlanta, GA, USA; Department of Psychology, Emory University, Atlanta, GA, USA.
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Memory loss in a nonnavigational spatial task after hippocampal inactivation in monkeys. Proc Natl Acad Sci U S A 2014; 111:4315-20. [PMID: 24591610 DOI: 10.1073/pnas.1320562111] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
The hippocampus has a well-documented role for spatial navigation across species, but its role for spatial memory in nonnavigational tasks is uncertain. In particular, when monkeys are tested in tasks that do not require navigation, spatial memory seems unaffected by lesions of the hippocampus. However, the interpretation of these results is compromised by long-term compensatory adaptation occurring in the days and weeks after lesions. To test the hypothesis that hippocampus is necessary for nonnavigational spatial memory, we selected a technique that avoids long-term compensatory adaptation. We transiently disrupted hippocampal function acutely at the time of testing by microinfusion of the glutamate receptor antagonist kynurenate. Animals were tested on a self-ordered spatial memory task, the Hamilton Search Task. In the task, animals are presented with an array of eight boxes, each containing a food reinforcer; one box may be opened per trial, with trials separated by a delay. Only the spatial location of the boxes serves as a cue to solve the task. The optimal strategy is to open each box once without returning to previously visited locations. Transient inactivation of hippocampus reduced performance to chance levels in a delay-dependent manner. In contrast, no deficits were seen when boxes were marked with nonspatial cues (color). These results clearly document a role for hippocampus in nonnavigational spatial memory in macaques and demonstrate the efficacy of pharmacological inactivation of this structure in this species. Our data bring the role of the hippocampus in monkeys into alignment with the broader framework of hippocampal function.
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Howell BR, McCormack KM, Grand AP, Sawyer NT, Zhang X, Maestripieri D, Hu X, Sanchez MM. Brain white matter microstructure alterations in adolescent rhesus monkeys exposed to early life stress: associations with high cortisol during infancy. BIOLOGY OF MOOD & ANXIETY DISORDERS 2013; 3:21. [PMID: 24289263 PMCID: PMC3880213 DOI: 10.1186/2045-5380-3-21] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/19/2013] [Accepted: 10/28/2013] [Indexed: 12/13/2022]
Abstract
BACKGROUND Early adverse experiences, especially those involving disruption of the mother-infant relationship, are detrimental for proper socioemotional development in primates. Humans with histories of childhood maltreatment are at high risk for developing psychopathologies including depression, anxiety, substance abuse, and behavioral disorders. However, the underlying neurodevelopmental alterations are not well understood. Here we used a nonhuman primate animal model of infant maltreatment to study the long-term effects of this early life stress on brain white matter integrity during adolescence, its behavioral correlates, and the relationship with early levels of stress hormones. METHODS Diffusion tensor imaging and tract based spatial statistics were used to investigate white matter integrity in 9 maltreated and 10 control animals during adolescence. Basal plasma cortisol levels collected at one month of age (when abuse rates were highest) were correlated with white matter integrity in regions with group differences. Total aggression was also measured and correlated with white matter integrity. RESULTS We found significant reductions in white matter structural integrity (measured as fractional anisotropy) in the corpus callosum, occipital white matter, external medullary lamina, as well as in the brainstem of adolescent rhesus monkeys that experienced maternal infant maltreatment. In most regions showing fractional anisotropy reductions, opposite effects were detected in radial diffusivity, without changes in axial diffusivity, suggesting that the alterations in tract integrity likely involve reduced myelin. Moreover, in most regions showing reduced white matter integrity, this was associated with elevated plasma cortisol levels early in life, which was significantly higher in maltreated than in control infants. Reduced fractional anisotropy in occipital white matter was also associated with increased social aggression. CONCLUSIONS These findings highlight the long-term impact of infant maltreatment on brain white matter structural integrity, particularly in tracts involved in visual processing, emotional regulation, and somatosensory and motor integration. They also suggest a relationship between elevations in stress hormones detected in maltreated animals during infancy and long-term brain white matter structural effects.
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Affiliation(s)
- Brittany R Howell
- Department of Psychiatry & Behavioral Sciences, Emory University, 101 Woodruff Circle, WMB Suite 4000, Atlanta, GA 30322, USA.
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13
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Zhao X, Pu J, Fan Y, Niu X, Yu D, Zhang Y. Characteristics of diffusion-tensor imaging for healthy adult rhesus monkey brains. Neural Regen Res 2013; 8:2951-61. [PMID: 25206616 PMCID: PMC4146173 DOI: 10.3969/j.issn.1673-5374.2013.31.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2012] [Accepted: 03/27/2013] [Indexed: 11/18/2022] Open
Abstract
Diffusion-tensor imaging can be used to observe the microstructure of brain tissue. Fractional sotropy reflects the integrity of white matter fibers. Fractional anisotropy of a young adult brain is low in gray matter, high in white matter, and highest in the splenium of the corpus callosum. Thus, we selected the anterior and posterior limbs of the internal capsule, head of the caudate nucleus, semioval center, thalamus, and corpus callosum (splenium and genu) as regions of interest when using diffusion-tensor imaging to observe fractional anisotropy of major white matter fiber tracts and the deep gray matter of healthy rhesus monkeys aged 4-8 years. Results showed no laterality ferences in fractional anisotropy values. Fractional anisotropy values were low in the head of date nucleus and thalamus in gray matter. Fractional anisotropy values were highest in the splenium of corpus callosum in the white matter, followed by genu of the corpus callosum and the posterior limb of the internal capsule. Fractional anisotropy values were lowest in the semioval center and posterior limb of internal capsule. These results suggest that fractional anisotropy values in major white matter fibers and the deep gray matter of 4-8-year-old rhesus monkeys are similar to those of healthy young people.
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Affiliation(s)
- Xinxiang Zhao
- Department of Radiology, Second Affiliated Hospital of Kunming Medical University, Kunming 650101, Yunnan Province, China
| | - Jun Pu
- Department of Neurosurgery, Second Affiliated Hospital of Kunming Medical University, Kunming 650101, Yunnan Province, China,
Corresponding author: Jun Pu, Associate chief physician, Department of Neurosurgery, Second Affiliated Hospital of Kunming Medical University, Kunming 650101, Yunnan Province, China. ; . (N20120814010)
| | - Yaodong Fan
- Department of Neurosurgery, Third Affiliated Hospital of Kunming Medical University, Kunming 650106, Yunnan Province, China
| | - Xiaoqun Niu
- Department of Pneumology, Second Affiliated Hospital of Kunming Medical University, Kunming 650101, Yunnan Province, China
| | - Danping Yu
- Yiwu Hospital Affiliated to Zhejiang University School of Medicine, Yiwu 322001, Zhejiang Province, China
| | - Yanglin Zhang
- Department of Radiology, Second Affiliated Hospital of Kunming Medical University, Kunming 650101, Yunnan Province, China
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Howell BR, Godfrey J, Gutman DA, Michopoulos V, Zhang X, Nair G, Hu X, Wilson ME, Sanchez MM. Social subordination stress and serotonin transporter polymorphisms: associations with brain white matter tract integrity and behavior in juvenile female macaques. Cereb Cortex 2013; 24:3334-49. [PMID: 23908263 DOI: 10.1093/cercor/bht187] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
We examined the relationship between social rank and brain white matter (WM) microstructure, and socioemotional behavior, and its modulation by serotonin (5HT) transporter (5HTT) polymorphisms in prepubertal female macaques. Using diffusion tensor imaging and tract-based spatial statistics, social status differences were found in medial prefrontal cortex (mPFC) WM and cortico-thalamic tracts, with subordinates showing higher WM structural integrity (measured as fractional anisotropy, FA) than dominant animals. 5HTT genotype-related differences were detected in the posterior limb of the internal capsule, where s-variants had higher FA than l/l animals. Status by 5HTT interaction effects were found in (1) external capsule (middle longitudinal fasciculus), (2) parietal WM, and (3) short-range PFC tracts, with opposite effects in dominant and subordinate animals. In most regions showing FA differences, opposite differences were detected in radial diffusivity, but none in axial diffusivity, suggesting that differences in tract integrity likely involve differences in myelin. These findings highlight that differences in social rank are associated with differences in WM structural integrity in juveniles, particularly in tracts connecting prefrontal, sensory processing, motor and association regions, sometimes modulated by 5HTT genotype. Differences in these tracts were associated with increased emotional reactivity in subordinates, particularly with higher submissive and fear behaviors.
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Affiliation(s)
- Brittany R Howell
- Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, GA, USA Division of Developmental and Cognitive Neuroscience, Yerkes National Primate Research Center
| | - Jodi Godfrey
- Division of Developmental and Cognitive Neuroscience, Yerkes National Primate Research Center
| | | | - Vasiliki Michopoulos
- Division of Developmental and Cognitive Neuroscience, Yerkes National Primate Research Center
| | - Xiaodong Zhang
- Division of Neuropharmacology and Neurologic Diseases and Yerkes Imaging Center, Yerkes National Primate Research Center, Emory University, Atlanta, GA, USA and
| | - Govind Nair
- Department of Biomedical Engineering, Emory University and Georgia Institute of Technology, Atlanta, GA, USA
| | - Xiaoping Hu
- Department of Biomedical Engineering, Emory University and Georgia Institute of Technology, Atlanta, GA, USA
| | - Mark E Wilson
- Division of Developmental and Cognitive Neuroscience, Yerkes National Primate Research Center
| | - Mar M Sanchez
- Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, GA, USA Division of Developmental and Cognitive Neuroscience, Yerkes National Primate Research Center
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Janve VA, Zu Z, Yao SY, Li K, Zhang FL, Wilson KJ, Ou X, Does MD, Subramaniam S, Gochberg DF. The radial diffusivity and magnetization transfer pool size ratio are sensitive markers for demyelination in a rat model of type III multiple sclerosis (MS) lesions. Neuroimage 2013; 74:298-305. [PMID: 23481461 DOI: 10.1016/j.neuroimage.2013.02.034] [Citation(s) in RCA: 91] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2012] [Revised: 01/31/2013] [Accepted: 02/19/2013] [Indexed: 10/27/2022] Open
Abstract
Determining biophysical sensitivity and specificity of quantitative magnetic resonance imaging is essential to develop effective imaging metrics of neurodegeneration. Among these metrics, apparent pool size ratio (PSR) from quantitative magnetization transfer (qMT) imaging and radial diffusivity (RD) from diffusion tensor imaging (DTI) are both known to relate to histological measure of myelin density and integrity. However their relative sensitivities towards quantitative myelin detection are unknown. In this study, we correlated high-resolution quantitative magnetic resonance imaging measures of subvoxel tissue structures with corresponding quantitative myelin histology in a lipopolysaccharide (LPS) mediated animal model of MS. Specifically, we acquired quantitative magnetization transfer (qMT) and diffusion tensor imaging (DTI) metrics (on the same tissue sample) in an animal model system of type III oligodendrogliopathy which lacked prominent lymphocytic infiltration, a system that had not been previously examined with quantitative MRI. We find that the qMT measured apparent pool size ratio (PSR) showed the strongest correlation with a histological measure of myelin content. DTI measured RD showed the next strongest correlation, and other DTI and relaxation parameters (such as the longitudinal relaxation rate (R1f) or fractional anisotropy (FA)) showed considerably weaker correlations with myelin content.
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Affiliation(s)
- Vaibhav A Janve
- Institute of Imaging Science, Vanderbilt University, Nashville, TN 37232-2310, USA
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Koenig KA, Sakaie KE, Lowe MJ, Lin J, Stone L, Bermel RA, Beall EB, Rao SM, Trapp BD, Phillips MD. High spatial and angular resolution diffusion-weighted imaging reveals forniceal damage related to memory impairment. Magn Reson Imaging 2013; 31:695-9. [PMID: 23295147 DOI: 10.1016/j.mri.2012.10.030] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2012] [Revised: 10/29/2012] [Accepted: 10/30/2012] [Indexed: 01/03/2023]
Abstract
INTRODUCTION Diffusion tensor imaging (DTI) measures in patients with multiple sclerosis (MS), particularly those measures associated with a specific white matter pathway, have consistently shown correlations with function. This study sought to investigate correlations between DTI measures in the fornix and common cognitive deficits in MS patients, including episodic memory, working memory and attention. MATERIALS AND METHODS Patients with MS and group age- and sex-matched controls underwent high-resolution diffusion scanning (1-mm isotropic voxels) and cognitive testing. Manually drawn forniceal regions of interest were applied to individual maps of tensor-derived measures, and mean values of transverse diffusivity (TD), mean diffusivity (MD), longitudinal diffusivity (LD) and fractional anisotropy (FA) were calculated. RESULTS In 40 patients with MS [mean age ± S.D.=42.55 ± 9.1 years; Expanded Disability Status Scale (EDSS)=2.0 ± 1.2; Multiple Sclerosis Functional Composite (MSFC) score=0.38 ± 0.46] and 20 healthy controls (mean age ± S.D.=41.35 ± 9.7 years; EDSS=0.0 ± 0; MSFC score=0.74 ± 0.24), we found that FA, MD and TD values in the fornix were significantly different between groups (P<.03), and patient performance on the Brief Visuospatial Memory Test-Revised (BVMT-R) was correlated with DTI measures (P<.03). DISCUSSION These results are consistent with findings of axonal degeneration in MS and support the use of DTI as an indicator of disease progression.
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A diffusion tensor brain template for rhesus macaques. Neuroimage 2011; 59:306-18. [PMID: 21803162 DOI: 10.1016/j.neuroimage.2011.07.029] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2011] [Revised: 06/27/2011] [Accepted: 07/07/2011] [Indexed: 11/22/2022] Open
Abstract
Diffusion tensor imaging (DTI) is a powerful and noninvasive imaging method for characterizing tissue microstructure and white matter organization in the brain. While it has been applied extensively in research studies of the human brain, DTI studies of non-human primates have been performed only recently. The growing application of DTI in rhesus monkey studies would significantly benefit from a standardized framework to compare findings across different studies. A very common strategy for image analysis is to spatially normalize (co-register) the individual scans to a representative template space. This paper presents the development of a DTI brain template, UWRMAC-DTI271, for adolescent Rhesus Macaque (Macaca mulatta) monkeys. The template was generated from 271 rhesus monkeys, collected as part of a unique brain imaging genetics study. It is the largest number of animals ever used to generate a computational brain template, which enables the generation of a template that has high image quality and accounts for variability in the species. The quality of the template is further ensured with the use of DTI-TK, a well-tested and high-performance DTI spatial normalization method in human studies. We demonstrated its efficacy in monkey studies for the first time by comparing it to other commonly used scalar-methods for DTI normalization. It is anticipated that this template will play an important role in facilitating cross-site voxelwise DTI analyses in Rhesus Macaques. Such analyses are crucial in investigating the role of white matter structure in brain function, development, and other psychopathological disorders for which there are well-validated non-human primate models.
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