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Liu Z, Shu K, Geng Y, Cai C, Kang H. Deep brain stimulation of fornix in Alzheimer's disease: From basic research to clinical practice. Eur J Clin Invest 2023; 53:e13995. [PMID: 37004153 DOI: 10.1111/eci.13995] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 03/13/2023] [Accepted: 03/23/2023] [Indexed: 04/03/2023]
Abstract
Alzheimer's disease (AD) is one of the most common progressive neurodegenerative diseases associated with the degradation of memory and cognitive ability. Current pharmacotherapies show little therapeutic effect in AD treatment and still cannot prevent the pathological progression of AD. Deep brain stimulation (DBS) has shown to enhance memory in morbid obese, epilepsy and traumatic brain injury patients, and cognition in Parkinson's disease (PD) patients deteriorates during DBS off. Some relevant animal studies and clinical trials have been carried out to discuss the DBS treatment for AD. Reviewing the fornix trials, no unified conclusion has been reached about the clinical benefits of DBS in AD, and the dementia ratings scale has not been effectively improved in the long term. However, some patients have presented promising results, such as improved glucose metabolism, increased connectivity in cognition-related brain regions and even elevated cognitive function rating scale scores. The fornix plays an important regulatory role in memory, attention, and emotion through its complex fibre projection to cognition-related structures, making it a promising target for DBS for AD treatment. Moreover, the current stereotaxic technique and various evaluation methods have provided references for the operator to select accurate stimulation points. Related adverse events and relatively higher costs in DBS have been emphasized. In this article, we summarize and update the research progression on fornix DBS in AD and seek to provide a reliable reference for subsequent experimental studies on DBS treatment of AD.
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Affiliation(s)
- Zhikun Liu
- Department of Neurosurgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei Province, China
| | - Kai Shu
- Department of Neurosurgery, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei Province, China
| | - Yumei Geng
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei Province, China
| | - Chang Cai
- National Engineering Research Center for E-Learning, Central China Normal University, Wuhan, Hubei Province, China
| | - Huicong Kang
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei Province, China
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Ma J, McGlade EC, Huber RS, Lyoo IK, Renshaw PF, Yurgelun-Todd DA. Overweight/Obesity-related microstructural alterations of the fimbria-fornix in the ABCD study: The role of aerobic physical activity. PLoS One 2023; 18:e0287682. [PMID: 37437033 PMCID: PMC10337868 DOI: 10.1371/journal.pone.0287682] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Accepted: 06/08/2023] [Indexed: 07/14/2023] Open
Abstract
Childhood overweight/obesity has been associated with negative consequences related to brain function and may involve alterations in white matter pathways important for cognitive and emotional processing. Aerobic physical activity is a promising lifestyle factor that could restore white matter alterations. However, little is known about either regional white matter alterations in children with overweight/obesity or the effects of aerobic physical activity targeting the obesity-related brain alterations in children. Using a large-scale cross-sectional population-based dataset of US children aged 9 to 10 years (n = 8019), this study explored the associations between overweight/obesity and microstructure of limbic white matter tracts, and examined whether aerobic physical activity may reduce the overweight/obesity-related white matter alterations in children. The primary outcome measure was restriction spectrum imaging (RSI)-derived white matter microstructural integrity measures. The number of days in a week that children engaged in aerobic physical activity for at least 60 minutes per day was assessed. We found that females with overweight/obesity had lower measures of integrity of the fimbria-fornix, a major limbic-hippocampal white matter tract, than their lean peers, while this difference was not significant in males. We also found a positive relationship between the number of days of aerobic physical activity completed in a week and integrity measures of the fimbria-fornix in females with overweight/obesity. Our results provide cross-sectional evidence of sex-specific microstructural alteration in the fimbria-fornix in children with overweight/obesity and suggest that aerobic physical activity may play a role in reducing this alteration. Future work should examine the causal direction of the relationship between childhood overweight/obesity and brain alterations and evaluate potential interventions to validate the effects of aerobic physical activity on this relationship.
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Affiliation(s)
- Jiyoung Ma
- Department of Psychiatry, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- Diagnostic Neuroimaging Laboratory, Huntsman Mental Health Institute, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - Erin C. McGlade
- Department of Psychiatry, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- Diagnostic Neuroimaging Laboratory, Huntsman Mental Health Institute, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- George E. Wahlen Department of Veterans Affairs Medical Center, VA VISN 19 Mental Illness Research, Education and Clinical Center, Salt Lake City, Utah, United States of America
| | - Rebekah S. Huber
- Department of Psychiatry, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- Diagnostic Neuroimaging Laboratory, Huntsman Mental Health Institute, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
| | - In Kyoon Lyoo
- Department of Psychiatry, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- Diagnostic Neuroimaging Laboratory, Huntsman Mental Health Institute, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- Ewha Brain Institute, Ewha W. University, Seoul, South Korea
| | - Perry F. Renshaw
- Department of Psychiatry, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- Diagnostic Neuroimaging Laboratory, Huntsman Mental Health Institute, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- George E. Wahlen Department of Veterans Affairs Medical Center, VA VISN 19 Mental Illness Research, Education and Clinical Center, Salt Lake City, Utah, United States of America
| | - Deborah A. Yurgelun-Todd
- Department of Psychiatry, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- Diagnostic Neuroimaging Laboratory, Huntsman Mental Health Institute, University of Utah School of Medicine, Salt Lake City, Utah, United States of America
- George E. Wahlen Department of Veterans Affairs Medical Center, VA VISN 19 Mental Illness Research, Education and Clinical Center, Salt Lake City, Utah, United States of America
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Spencer APC, Lequin MH, de Vries LS, Brooks JCW, Jary S, Tonks J, Cowan FM, Thoresen M, Chakkarapani E. Mammillary body abnormalities and cognitive outcomes in children cooled for neonatal encephalopathy. Dev Med Child Neurol 2023; 65:792-802. [PMID: 36335569 PMCID: PMC10952753 DOI: 10.1111/dmcn.15453] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Revised: 10/07/2022] [Accepted: 10/12/2022] [Indexed: 11/07/2022]
Abstract
AIM To evaluate mammillary body abnormalities in school-age children without cerebral palsy treated with therapeutic hypothermia for neonatal hypoxic-ischaemic encephalopathy (cases) and matched controls, and associations with cognitive outcome, hippocampal volume, and diffusivity in the mammillothalamic tract (MTT) and fornix. METHOD Mammillary body abnormalities were scored from T1-weighted magnetic resonance imaging (MRI) in 32 cases and 35 controls (median age [interquartile range] 7 years [6 years 7 months-7 years 7 months] and 7 years 4 months [6 years 7 months-7 years 7 months] respectively). Cognition was assessed using the Wechsler Intelligence Scale for Children, Fourth Edition. Hippocampal volume (normalized by total brain volume) was measured from T1-weighted MRI. Radial diffusivity and fractional anisotropy were measured in the MTT and fornix, from diffusion-weighted MRI using deterministic tractography. RESULTS More cases than controls had mammillary body abnormalities (34% vs 0%; p < 0.001). Cases with abnormal mammillary bodies had lower processing speed (p = 0.016) and full-scale IQ (p = 0.028) than cases without abnormal mammillary bodies, and lower scores than controls in all cognitive domains (p < 0.05). Cases with abnormal mammillary bodies had smaller hippocampi (left p = 0.016; right p = 0.004) and increased radial diffusivity in the right MTT (p = 0.004) compared with cases without mammillary body abnormalities. INTERPRETATION Cooled children with mammillary body abnormalities at school-age have reduced cognitive scores, smaller hippocampi, and altered MTT microstructure compared with those without mammillary body abnormalities, and matched controls. WHAT THIS PAPER ADDS Cooled children are at higher risk of mammillary body abnormalities than controls. Abnormal mammillary bodies are associated with reduced cognitive scores and smaller hippocampi. Abnormal mammillary bodies are associated with altered mammillothalamic tract diffusivity.
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Affiliation(s)
- Arthur P. C. Spencer
- Translational Health Sciences, Bristol Medical SchoolUniversity of BristolBristolUK
- Clinical Research and Imaging CentreUniversity of BristolBristolUK
| | - Maarten H. Lequin
- Department of Radiology and Nuclear MedicineUniversity Medical Center Utrecht/Wilhelmina Children's HospitalUtrechtthe Netherlands
- Princess Máxima Center for Pediatric OncologyUtrechtthe Netherlands
| | - Linda S. de Vries
- Department of NeonatologyUniversity Medical Center UtrechtUtrechtthe Netherlands
- Department of NeonatologyLeiden University Medical CenterLeidenthe Netherlands
| | - Jonathan C. W. Brooks
- Clinical Research and Imaging CentreUniversity of BristolBristolUK
- School of PsychologyUniversity of East AngliaNorwichUK
| | - Sally Jary
- Translational Health Sciences, Bristol Medical SchoolUniversity of BristolBristolUK
| | - James Tonks
- Translational Health Sciences, Bristol Medical SchoolUniversity of BristolBristolUK
- University of Exeter Medical SchoolExeterUK
| | - Frances M. Cowan
- Translational Health Sciences, Bristol Medical SchoolUniversity of BristolBristolUK
- Department of PaediatricsImperial College LondonLondonUK
| | - Marianne Thoresen
- Translational Health Sciences, Bristol Medical SchoolUniversity of BristolBristolUK
- Faculty of MedicineInstitute of Basic Medical Sciences, University of OsloOsloNorway
| | - Ela Chakkarapani
- Translational Health Sciences, Bristol Medical SchoolUniversity of BristolBristolUK
- Neonatal Intensive Care UnitSt Michael's Hospital, University Hospitals Bristol and Weston NHS Foundation TrustBristolUK
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Gabery S, Kwa JE, Cheong RY, Baldo B, Ferrari Bardile C, Tan B, McLean C, Georgiou-Karistianis N, Poudel GR, Halliday G, Pouladi MA, Petersén Å. Early white matter pathology in the fornix of the limbic system in Huntington disease. Acta Neuropathol 2021; 142:791-806. [PMID: 34448021 PMCID: PMC8500909 DOI: 10.1007/s00401-021-02362-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2021] [Revised: 08/09/2021] [Accepted: 08/18/2021] [Indexed: 12/13/2022]
Abstract
Huntington disease (HD) is a fatal neurodegenerative disorder caused by an expanded CAG repeat in the huntingtin (HTT) gene. The typical motor symptoms have been associated with basal ganglia pathology. However, psychiatric and cognitive symptoms often precede the motor component and may be due to changes in the limbic system. Recent work has indicated pathology in the hypothalamus in HD but other parts of the limbic system have not been extensively studied. Emerging evidence suggests that changes in HD also include white matter pathology. Here we investigated if the main white matter tract of the limbic system, the fornix, is affected in HD. We demonstrate that the fornix is 34% smaller already in prodromal HD and 41% smaller in manifest HD compared to controls using volumetric analyses of MRI of the IMAGE-HD study. In post-mortem fornix tissue from HD cases, we confirm the smaller fornix volume in HD which is accompanied by signs of myelin breakdown and reduced levels of the transcription factor myelin regulating factor but detect no loss of oligodendrocytes. Further analyses using RNA-sequencing demonstrate downregulation of oligodendrocyte identity markers in the fornix of HD cases. Analysis of differentially expressed genes based on transcription-factor/target-gene interactions also revealed enrichment for binding sites of SUZ12 and EZH2, components of the Polycomb Repressive Complex 2, as well as RE1 Regulation Transcription Factor. Taken together, our data show that there is early white matter pathology of the fornix in the limbic system in HD likely due to a combination of reduction in oligodendrocyte genes and myelin break down.
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Affiliation(s)
- Sanaz Gabery
- Translational Neuroendocrine Research Unit, Department of Experimental Medical Science, Lund University, BMC D11, 22184, Lund, Sweden
| | - Jing Eugene Kwa
- Translational Laboratory in Genetic Medicine (TLGM), Agency for Science, Technology and Research (A*STAR), Singapore, 138648, Singapore
| | - Rachel Y Cheong
- Translational Neuroendocrine Research Unit, Department of Experimental Medical Science, Lund University, BMC D11, 22184, Lund, Sweden
| | - Barbara Baldo
- Translational Neuroendocrine Research Unit, Department of Experimental Medical Science, Lund University, BMC D11, 22184, Lund, Sweden
- Evotec SE, HD Research and Translational Sciences, 22419, Hamburg, Germany
| | - Costanza Ferrari Bardile
- Translational Laboratory in Genetic Medicine (TLGM), Agency for Science, Technology and Research (A*STAR), Singapore, 138648, Singapore
- Department of Medical Genetics, British Columbia Children's Hospital Research Institute, University of British Columbia, Vancouver, V5Z 4H4, Canada
| | - Brendan Tan
- School of Psychological Sciences, Monash University, Clayton, VIC, 3180, Australia
| | - Catriona McLean
- Department of Pathology, Alfred Hospital, Melbourne, VIC, Australia
| | | | - Govinda R Poudel
- School of Psychological Sciences, Monash University, Clayton, VIC, 3180, Australia
| | - Glenda Halliday
- The Brain and Mind Centre and Faculty of Medicine and Health, School of Medical Sciences, University of Sydney, Sydney, Australia
| | - Mahmoud A Pouladi
- Translational Laboratory in Genetic Medicine (TLGM), Agency for Science, Technology and Research (A*STAR), Singapore, 138648, Singapore
- Department of Medical Genetics, British Columbia Children's Hospital Research Institute, University of British Columbia, Vancouver, V5Z 4H4, Canada
- Department of Physiology, National University of Singapore (NUS), Singapore, 117597, Singapore
| | - Åsa Petersén
- Translational Neuroendocrine Research Unit, Department of Experimental Medical Science, Lund University, BMC D11, 22184, Lund, Sweden.
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Senova S, Fomenko A, Gondard E, Lozano AM. Anatomy and function of the fornix in the context of its potential as a therapeutic target. J Neurol Neurosurg Psychiatry 2020; 91:547-559. [PMID: 32132227 PMCID: PMC7231447 DOI: 10.1136/jnnp-2019-322375] [Citation(s) in RCA: 48] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Revised: 02/10/2020] [Accepted: 02/15/2020] [Indexed: 02/07/2023]
Abstract
The fornix is a white matter bundle located in the mesial aspect of the cerebral hemispheres, which connects various nodes of a limbic circuitry and is believed to play a key role in cognition and episodic memory recall. As the most prevalent cause of dementia, Alzheimer's disease (AD) dramatically impairs the quality of life of patients and imposes a significant societal burden on the healthcare system. As an established treatment for movement disorders, deep brain stimulation (DBS) is currently being investigated in preclinical and clinical studies for treatment of memory impairment in AD by modulating fornix activity. Optimal target and stimulation parameters to potentially rescue memory deficits have yet to be determined. The aim of this review is to consolidate the structural and functional aspects of the fornix in the context of neuromodulation for memory deficits. We first present an anatomical and functional overview of the fibres and structures interconnected by the fornix. Recent evidence from preclinical models suggests that the fornix is subdivided into two distinct functional axes: a septohippocampal pathway and a subiculothalamic pathway. Each pathway's target and origin structures are presented, followed by a discussion of their oscillatory dynamics and functional connectivity. Overall, neuromodulation of each pathway of the fornix is discussed in the context of evidence-based forniceal DBS strategies. It is not yet known whether driving fornix activity can enhance cognition-optimal target and stimulation parameters to rescue memory deficits have yet to be determined.
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Affiliation(s)
- Suhan Senova
- Neurosurgery, Institut Mondor de recherche biomedicale, Créteil, Île-de-France, France
| | - Anton Fomenko
- Division of Neurosurgery, University of Toronto, Toronto, Ontario, Canada
- University Health Network, Toronto, Ontario, Canada
| | | | - Andres M Lozano
- Division of Neurosurgery, University of Toronto, Toronto, Ontario, Canada
- University Health Network, Toronto, Ontario, Canada
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Thierry M, Boluda S, Delatour B, Marty S, Seilhean D, Potier MC, Duyckaerts C. Human subiculo-fornico-mamillary system in Alzheimer's disease: Tau seeding by the pillar of the fornix. Acta Neuropathol 2020; 139:443-461. [PMID: 31822997 DOI: 10.1007/s00401-019-02108-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 11/29/2019] [Accepted: 11/30/2019] [Indexed: 02/07/2023]
Abstract
In Alzheimer's disease (AD), Tau and Aβ aggregates involve sequentially connected regions, sometimes distantly separated. These alterations were studied in the pillar of the fornix (PoF), an axonal tract, to analyse the role of axons in their propagation. The PoF axons mainly originate from the subicular neurons and project to the mamillary body. Forty-seven post-mortem cases at various Braak stages (Tau) and Thal phases (Aβ) were analysed by immunohistochemistry. The distribution of the lesions showed that the subiculum was affected before the mamillary body, but neither Tau aggregation nor Aβ deposition was consistently first. The subiculum and the mamillary body contained Gallyas positive neurofibrillary tangles, immunolabelled by AT8, TG3, PHF1, Alz50 and C3 Tau antibodies. In the PoF, only thin and fragmented threads were observed, exclusively in the cases with neurofibrillary tangles in the subiculum. The threads were made of Gallyas negative, AT8 and TG3 positive Tau. They were intra-axonal and devoid of paired helical filaments at electron microscopy. We tested PoF homogenates containing Tau AT8 positive axons in a Tau P301S biosensor HEK cell line and found a seeding activity. There was no Aβ immunoreactivity detected in the PoF. We could follow microcryodissected AT8 positive axons entering the mamillary body; contacts between Tau positive endings and Aβ positive diffuse or focal deposits were observed in CLARITY-cleared mamillary body. In conclusion, we show that non-fibrillary, hyperphosphorylated Tau is transported by the axons of the PoF from the subiculum to the mamillary body and has a seeding activity. Either Tau aggregation or Aβ accumulation may occur first in this system: this inconstant order is incompatible with a cause-and-effects relationship. However, both pathologies were correlated and intimately associated, indicating an interaction of the two processes, once initiated.
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Affiliation(s)
- Manon Thierry
- Alzheimer's and Prion Diseases Team, Paris Brain Institute, CNRS, UMR 7225, INSERM 1127, Sorbonne University UM75, Paris, France
- Laboratoire de Neuropathologie Raymond Escourolle, Pitié-Salpêtrière Hospital, APHP, Sorbonne University, 47, Blvd de l'Hôpital, 75651, Paris Cedex 13, France
| | - Susana Boluda
- Alzheimer's and Prion Diseases Team, Paris Brain Institute, CNRS, UMR 7225, INSERM 1127, Sorbonne University UM75, Paris, France
- Laboratoire de Neuropathologie Raymond Escourolle, Pitié-Salpêtrière Hospital, APHP, Sorbonne University, 47, Blvd de l'Hôpital, 75651, Paris Cedex 13, France
| | - Benoît Delatour
- Alzheimer's and Prion Diseases Team, Paris Brain Institute, CNRS, UMR 7225, INSERM 1127, Sorbonne University UM75, Paris, France
| | - Serge Marty
- Alzheimer's and Prion Diseases Team, Paris Brain Institute, CNRS, UMR 7225, INSERM 1127, Sorbonne University UM75, Paris, France
| | - Danielle Seilhean
- Laboratoire de Neuropathologie Raymond Escourolle, Pitié-Salpêtrière Hospital, APHP, Sorbonne University, 47, Blvd de l'Hôpital, 75651, Paris Cedex 13, France
| | - Marie-Claude Potier
- Alzheimer's and Prion Diseases Team, Paris Brain Institute, CNRS, UMR 7225, INSERM 1127, Sorbonne University UM75, Paris, France
| | - Charles Duyckaerts
- Alzheimer's and Prion Diseases Team, Paris Brain Institute, CNRS, UMR 7225, INSERM 1127, Sorbonne University UM75, Paris, France.
- Laboratoire de Neuropathologie Raymond Escourolle, Pitié-Salpêtrière Hospital, APHP, Sorbonne University, 47, Blvd de l'Hôpital, 75651, Paris Cedex 13, France.
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Fukushima S, Kurganov E, Hiratsuka D, Miyata S. Effect of fluoxetine on proliferation and/or survival of microglia and oligodendrocyte progenitor cells in the fornix and corpus callosum of the mouse brain. Pharmacol Rep 2020; 72:340-349. [PMID: 32109308 DOI: 10.1007/s43440-020-00079-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Revised: 11/23/2019] [Accepted: 12/30/2019] [Indexed: 02/06/2023]
Abstract
BACKGROUND Fluoxetine is one of the most widely prescribed antidepressants and a selective inhibitor of presynaptic 5-HT transporters. The fornix is the commissural and projection fiber that transmits signals from the hippocampus to other parts of the brain and opposite site of hippocampus. The corpus callosum (CC) is the largest of the commissural fibers that link the cerebral cortex of the left and right cerebral hemispheres. These brain regions play pivotal roles in cognitive functions, and functional abnormalities in these regions have been implicated in the development of various brain diseases. The purpose of the present study was to investigate the effects of fluoxetine on the proliferation and/or survival of microglia and oligodendrocyte progenitor cells (OPCs) in the fornix and CC, the white matter connecting cortical-limbic system, of the adult mouse brain. METHODS The effects of fluoxetine on the proliferation and/or survival of microglia and OPCs were examined in lipopolysaccharide (LPS)-treated and normal mice. Proliferating cells were detected in mice that drank water containing the thymidine analog, bromodeoxyuridine (BrdU), using immunohistochemistry. RESULT Fluoxetine significantly attenuated LPS-induced increases in the number of BrdU-labeled microglia and morphological activation from the ramified to ameboid shape, and decreased the number of BrdU-labeled OPCs under basal conditions. CONCLUSIONS The present results indicate that fluoxetine exerts inhibitory effects on LPS-induced increases in the proliferation and/or survival and morphological activation of microglia and basal proliferation and/or survival of OPCs in the fornix and CC of adult mice.
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Affiliation(s)
- Shohei Fukushima
- Department of Applied Biology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto, 606-8585, Japan
| | - Erkin Kurganov
- Department of Applied Biology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto, 606-8585, Japan
| | - Daishi Hiratsuka
- Department of Applied Biology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto, 606-8585, Japan
| | - Seiji Miyata
- Department of Applied Biology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto, 606-8585, Japan.
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Rabin JS, Perea RD, Buckley RF, Johnson KA, Sperling RA, Hedden T. Synergism between fornix microstructure and beta amyloid accelerates memory decline in clinically normal older adults. Neurobiol Aging 2019; 81:38-46. [PMID: 31207468 PMCID: PMC6732225 DOI: 10.1016/j.neurobiolaging.2019.05.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Revised: 05/07/2019] [Accepted: 05/09/2019] [Indexed: 01/09/2023]
Abstract
The fornix is the primary efferent white matter tract of the hippocampus and is implicated in episodic memory. In this study, we investigated whether baseline measures of altered fornix microstructure and elevated beta amyloid (Aβ) burden influence prospective cognitive decline. A secondary goal examined whether Aβ burden is negatively associated with fornix microstructure. 253 clinically normal older adults underwent diffusion-weighted imaging and Pittsburgh Compound B positron emission tomography at baseline. We applied a novel streamline tractography protocol to reconstruct a fornix bundle in native space. Cognition was measured annually in domains of episodic memory, executive function, and processing speed (median follow-up = 4.0 ± 1.4 years). After controlling for covariates, linear mixed-effects models demonstrated an interaction of fornix microstructure with Aβ burden on episodic memory, such that combined lower fornix microstructure and higher Aβ burden was associated with accelerated decline. By contrast, associations with executive function and processing speed were not significant. There was no cross-sectional association between Aβ burden and fornix microstructure. In conclusion, altered fornix microstructure may accelerate memory decline in preclinical Alzheimer's disease.
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Affiliation(s)
- Jennifer S Rabin
- Department of Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA; Hurvitz Brain Sciences Research Program, Sunnybrook Research Institute, Toronto, Ontario, Canada
| | - Rodrigo D Perea
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Rachel F Buckley
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA; Florey Institutes of Neuroscience and Mental Health, Melbourne and Melbourne School of Psychological Science, University of Melbourne, Melbourne, Australia; Department of Neurology, Center for Alzheimer Research and Treatment, Brigham and Women's Hospital, Boston, MA, USA
| | - Keith A Johnson
- Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA; Department of Neurology, Center for Alzheimer Research and Treatment, Brigham and Women's Hospital, Boston, MA, USA; Division of Nuclear Medicine and Molecular Imaging, Massachusetts General Hospital, Boston, MA, USA
| | - Reisa A Sperling
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA; Department of Neurology, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA; Department of Neurology, Center for Alzheimer Research and Treatment, Brigham and Women's Hospital, Boston, MA, USA
| | - Trey Hedden
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA; Department of Neurology, Icahn School of Medicine at Mount Sinai, New York, NY, USA.
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Zou Y, Murray DE, Durazzo TC, Schmidt TP, Murray TA, Meyerhoff DJ. White matter microstructural correlates of relapse in alcohol dependence. Psychiatry Res Neuroimaging 2018; 281:92-100. [PMID: 30273793 PMCID: PMC6204088 DOI: 10.1016/j.pscychresns.2018.09.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/25/2017] [Revised: 09/14/2018] [Accepted: 09/14/2018] [Indexed: 12/15/2022]
Abstract
Identification of neural correlates of relapse to alcohol after treatment is clinically important as it may inform better substance abuse treatment. Few studies have specifically analyzed the white matter microstructure in treatment seekers as it might relate to relapse risk versus long-term abstinence. Using 4 Tesla diffusion tensor imaging, we compared two groups of one-month-abstinent treatment-seekers, who were classified based on their drinking status between six and nine months after treatment initiation. We hypothesized that subsequent relapsers had greater white matter microstructural deficits in specific brain regions than long-term abstainers. At one month of abstinence, 37 future relapsers versus 25 future abstainers had lower fractional anisotropy (a measure of axonal organization and membrane integrity) in the corpus callosum and right stria terminalis/fornix, higher diffusivity in the genu of the corpus callosum, left and right stria terminalis/fornix, and lower diffusivity in left anterior corona radiata. These differences existed despite similar lifetime and recent drinking and smoking histories in the groups. Longer smoking duration in relapsers was associated with lower fractional anisotropy in right stria terminalis/fornix. The study identified specific microstructural biomarkers of alcohol relapse risk in adults, contributing to the definition of a neurobiological relapse risk profile in alcohol use disorder.
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Affiliation(s)
- Yukai Zou
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, IN 47906, United States; College of Veterinary Medicine, Purdue University, West Lafayette, IN 47906, United States
| | - Donna E Murray
- Center for Imaging of Neurodegenerative Diseases (CIND), San Francisco VA Medical Center, San Francisco, CA 94121, United States; Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA 94143, United States
| | - Timothy C Durazzo
- Department of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, CA 94305, United States; Mental Illness Research Mental Illness Research and Education Clinical Centers, Sierra-Pacific War Related Illness and Injury Study Center, VA Palo Alto Health Care System, Palo Alto, CA 94304, United States
| | - Thomas P Schmidt
- Center for Imaging of Neurodegenerative Diseases (CIND), San Francisco VA Medical Center, San Francisco, CA 94121, United States
| | - Troy A Murray
- Center for Imaging of Neurodegenerative Diseases (CIND), San Francisco VA Medical Center, San Francisco, CA 94121, United States
| | - Dieter J Meyerhoff
- Center for Imaging of Neurodegenerative Diseases (CIND), San Francisco VA Medical Center, San Francisco, CA 94121, United States; Department of Radiology and Biomedical Imaging, University of California San Francisco, San Francisco, CA 94143, United States.
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10
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Song Z, Farrell ME, Chen X, Park DC. Longitudinal accrual of neocortical amyloid burden is associated with microstructural changes of the fornix in cognitively normal adults. Neurobiol Aging 2018; 68:114-122. [PMID: 29602495 PMCID: PMC5993596 DOI: 10.1016/j.neurobiolaging.2018.02.021] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Revised: 02/20/2018] [Accepted: 02/21/2018] [Indexed: 02/02/2023]
Abstract
The fornix and parahippocampal cingulum are 2 major limbic tracts in the core memory network of the hippocampus. Although these fiber tracts are known to degrade with Alzheimer's disease (AD), little is known about their vulnerability in the asymptomatic phase of AD. In this longitudinal study of cognitively normal adults, we assessed amyloid-beta (Aβ) plaques using positron emission tomography and white matter microstructure using diffusion tensor imaging. We found that an increase of neocortical Aβ burden over time was associated with an increase of radial diffusivity in the fornix but not in the parahippocampal cingulum. The effect of increasing neocortical Aβ burden on the fornix remained significant after controlling for baseline measures, head motion, global brain atrophy, regional Aβ burden in the hippocampus, or microstructural changes in the global white matter. In addition, microstructural changes in the fornix were not associated with decline of episodic memory or other cognitive abilities. Our findings suggest that microstructural changes in the fornix may be an early sign in the asymptomatic phase of AD.
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Affiliation(s)
- Zhuang Song
- Center for Vital Longevity, University of Texas at Dallas, Dallas, TX, USA.
| | - Michelle E Farrell
- Center for Vital Longevity, University of Texas at Dallas, Dallas, TX, USA
| | - Xi Chen
- Center for Vital Longevity, University of Texas at Dallas, Dallas, TX, USA
| | - Denise C Park
- Center for Vital Longevity, University of Texas at Dallas, Dallas, TX, USA; Department of Psychiatry, University of Texas Southwestern Medical Center, Dallas, TX, USA
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11
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Abstract
It is not clear whether the fornix and cingulum are involved in cognition after putaminal hemorrhage (PH). We investigated structural changes and differences of the neural tracts, and the relationship between the integrity of the neural tracts and cognition not only at the affected but also at the unaffected side.Sixteen patients with left chronic putaminal hemorrhage and 20 healthy volunteers were enrolled. Using diffusion tensor tractography (DTT), we compared fiber number (FN), fractional anisotropy (FA), and apparent diffusion coefficient (ADC) of the neural tracts between patient and control groups. The relationship between the neural tract parameters and neuropsychological results was also analyzed.The left fornix FN was significantly lower than the right fornix FN in the patient group. Except for the cingulum FA, the neural tracts parameters for both the affected and unaffected hemispheres differed significantly between the groups. The fornix FA and ADC at the affected side were significantly correlated with intelligence quotient (IQ), mini-mental status examination (MMSE), and short-term memory. Interestingly, the fornix ADC at the unaffected side was significantly correlated with MMSE. However, none of the cingulum parameters was correlated with neuropsychological results.The fornix integrity is critical for cognitive impairment after putaminal hemorrhage.
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Affiliation(s)
- Jeong-Hee Yang
- Division of Brain Fusion Research, Biomedical Research Center, Ulsan University Hospital
| | - Han Do Lee
- Department of Physical Medicine and Rehabilitation, College of Medicine, Yeungnam University, Taegu
| | - So Young Kwak
- Department of Physical Medicine and Rehabilitation, College of Medicine, Yeungnam University, Taegu
| | - Ki Hyun Byun
- Department of Physical Medicine and Rehabilitation, University of Ulsan College of Medicine
| | - Sung Ho Park
- Department of Neurosurgery, Ulsan University Hospital, Ulsan, Republic of Korea
| | - Dongseok Yang
- Department of Physical Medicine and Rehabilitation, University of Ulsan College of Medicine
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12
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Almaguer-Melian W, Mercerón-Martinez D, Delgado-Ocaña S, Alberti-Amador E, Gonzalez-Gómez R, Bergado JA. Erythropoietin improves object placement recognition memory in a time dependent manner in both, uninjured animals and fimbria-fornix-lesioned male rats. Horm Behav 2018; 100:94-99. [PMID: 29548782 DOI: 10.1016/j.yhbeh.2018.03.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Revised: 02/21/2018] [Accepted: 03/11/2018] [Indexed: 10/17/2022]
Abstract
An increasing number of reports sustain a possible role of erythropoietin (EPO) as neuroprotective agent. In two previous articles we have evaluated EPO as plasticity promoting agent, and to contribute the restoration of brain function affected by acquired damage. We have shown that EPO is able to induce an increased synaptic efficacy in vivo along with a plasticity promoting effect. In the Morris water maze EPO administration to fimbria-fornix lesioned male rats induces a significant improvement of their spatial memory, affected by the lesion. Singularly, EPO was only effective when administered shortly after training (10 min) but not after several hours (5 h), suggesting a specific EPO effect on time dependent plasticity process. In the present paper we have expanded this line of evidence using a low stress paradigm of object placement recognition in lesioned and healthy male rats. The memory trace in this model is short-lasting; animals could recognize the change in object position when tested 24 h after, but not 48 or 72 h after the acquisition session. EPO administration 10 min after acquisition significantly prolongs retention to, at least, 72 h in healthy rats. No effect was seen if EPO was administered 5 h after training, suggesting a specific EPO modulatory effect on the consolidation process. Remarkably, early EPO treatment to fimbria fornix lesioned animals reverts the memory deficit caused by the lesion. An increased expression of the plasticity related gene arc, was also confirmed in the hippocampus and the prefrontal cortex, that is likely to be involved in the behavioral improvement observed.
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Affiliation(s)
- W Almaguer-Melian
- Centro Internacional de Restauración Neurológica (CIREN), Habana 11300, Cuba.
| | | | - S Delgado-Ocaña
- Centro Internacional de Restauración Neurológica (CIREN), Habana 11300, Cuba
| | - E Alberti-Amador
- Centro Internacional de Restauración Neurológica (CIREN), Habana 11300, Cuba.
| | | | - Jorge A Bergado
- Centro Internacional de Restauración Neurológica (CIREN), Habana 11300, Cuba; Universidad del Sinú "Elías Bechara Zainún", Montería, Colombia.
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13
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Kurumaji A, Itasaka M, Uezato A, Takiguchi K, Jitoku D, Hobo M, Nishikawa T. A distinctive abnormality of diffusion tensor imaging parameters in the fornix of patients with bipolar II disorder. Psychiatry Res Neuroimaging 2017; 266:66-72. [PMID: 28609689 DOI: 10.1016/j.pscychresns.2017.06.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/03/2017] [Revised: 06/05/2017] [Accepted: 06/06/2017] [Indexed: 12/01/2022]
Abstract
Diffusion tensor imaging (DTI) studies have revealed a changed integrity in the white matter of bipolar disorder. However, only a few investigations have examined bipolar II disorder (BP-II). A cross-sectional study was conducted to compare thirty-eight patients with BP-II (mean age = 38.26 years, F/M = 19/19) with thirty-eight age- and gender-matched healthy controls (mean age = 34.45 years, F/M = 18/20). Tract Based Spatial Statistics (TBSS) analysis of the fractional anisotropy (FA) was done with age, gender and education years as covariates, then a complementary atlas-based region-of-interest (ROI) analysis including the axial diffusivity (AD) and radial diffusivity (RD) was conducted to obtain further information. The patients with BP-II showed a significant decrease in FA in the corpus callosum (commissure fibers), fornix (association fibers) and right anterior corona radiata (projection fibers) compared to the controls. Moreover, a significant increase in the RD was observed in all of the fibers of the BP-II patients, while the AD significantly increased only in the fornix of the patients. Thus, in addition to the abnormal integrity of the commissure and projection fibers, the present study suggested an involvement of the limbic association fibers in the pathophysiology of BP-II induced by a distinctive neuropathology.
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Affiliation(s)
- Akeo Kurumaji
- Section of Psychiatry and Behavioral Sciences, Tokyo Medical and Dental University Graduate School, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8519, Japan.
| | - Michio Itasaka
- Section of Psychiatry and Behavioral Sciences, Tokyo Medical and Dental University Graduate School, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8519, Japan
| | - Akihito Uezato
- Section of Psychiatry and Behavioral Sciences, Tokyo Medical and Dental University Graduate School, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8519, Japan
| | - Kazuo Takiguchi
- Section of Psychiatry and Behavioral Sciences, Tokyo Medical and Dental University Graduate School, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8519, Japan
| | - Daisuke Jitoku
- Section of Psychiatry and Behavioral Sciences, Tokyo Medical and Dental University Graduate School, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8519, Japan
| | - Mizue Hobo
- Section of Psychiatry and Behavioral Sciences, Tokyo Medical and Dental University Graduate School, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8519, Japan
| | - Toru Nishikawa
- Section of Psychiatry and Behavioral Sciences, Tokyo Medical and Dental University Graduate School, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113-8519, Japan
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14
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Bennett IJ, Greenia DE, Maillard P, Sajjadi SA, DeCarli C, Corrada MM, Kawas CH. Age-related white matter integrity differences in oldest-old without dementia. Neurobiol Aging 2017; 56:108-114. [PMID: 28527525 PMCID: PMC5647141 DOI: 10.1016/j.neurobiolaging.2017.04.013] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Revised: 04/07/2017] [Accepted: 04/15/2017] [Indexed: 12/30/2022]
Abstract
Aging is known to have deleterious effects on cerebral white matter, yet little is known about these white matter alterations in advanced age. In this study, 94 oldest-old adults without dementia (90-103 years) underwent diffusion tensor imaging to assess relationships between chronological age and multiple measures of integrity in 18 white matter regions across the brain. Results revealed significant age-related declines in integrity in regions previously identified as being sensitive to aging in younger-old adults (corpus callosum, fornix, cingulum, external capsule). For the corpus callosum, the effect of age on genu fractional anisotropy was significantly weaker than the relationship between age and splenium fractional anisotropy. Importantly, age-related declines in white matter integrity did not differ in cognitively normal and cognitively impaired not demented oldest-old, suggesting that they were not solely driven by cognitive dysfunction or preclinical dementia in this advanced age group. Instead, white matter in these regions appears to remain vulnerable to normal aging processes through the 10th decade of life.
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Affiliation(s)
- Ilana J Bennett
- Department of Psychology, University of California, Riverside, CA, USA.
| | - Dana E Greenia
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, CA, USA
| | - Pauline Maillard
- Department of Neurology, University of California, Davis, CA, USA
| | - S Ahmad Sajjadi
- Department of Neurology, University of California, Irvine, CA, USA
| | - Charles DeCarli
- Department of Neurology, University of California, Davis, CA, USA; Alzheimer's Disease Center, University of California, Davis, CA, USA
| | - Maria M Corrada
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, CA, USA; Department of Neurology, University of California, Irvine, CA, USA; Department of Epidemiology, University of California, Irvine, CA, USA
| | - Claudia H Kawas
- Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, CA, USA; Department of Neurology, University of California, Irvine, CA, USA; Department of Epidemiology, University of California, Irvine, CA, USA; Department of Neurobiology and Behavior, University of California, Irvine, CA, USA
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15
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Tang SX, Feng QL, Wang GH, Duan S, Shan BC, Dai JP. Diffusion characteristics of the fornix in patients with Alzheimer's disease. Psychiatry Res Neuroimaging 2017; 265:72-76. [PMID: 28017479 DOI: 10.1016/j.pscychresns.2016.09.012] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Revised: 09/25/2016] [Accepted: 09/27/2016] [Indexed: 02/05/2023]
Abstract
White matter degradation is a major part of the pathogenesis of Alzheimer's disease (AD). The fornix is the predominant outflow tract from the hippocampus, and alterations to its microstructure in patients with AD are still being explored. Diffusion tensor imaging (DTI) is an in vivo neuroimaging technique that can provide unique information about alterations in tissue microstructure, which can indicate underlying neurobiological process at the microstructural level. In this prospective study, DTI was used to assess and analyze the microstructural features of the fornix in subjects with AD (n = 17), mild cognitive impairment (MCI; n = 12) and healthy controls (n = 17). DTI was performed using Explore DTI software and the FSL package. Within the fornix, patients with AD showed decreased fractional anisotropy values and length of fiber tracts of the fornix relative to healthy controls, but higher mean diffusivity values. MCI subjects showed a trend towards elevated mean diffusivity values in the fornix. The data suggest that DTI provides supporting information on the microstructural alteration of the fornix in patients with AD, and that these diffusion characteristics of the fornix may be helpful for the clinical diagnosis of AD.
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Affiliation(s)
- Shou Xian Tang
- Neuroimaging center, Department of Radiology, Beijing Tiantan Hospital, Capital Medical University,6 Tiantan Xili, Dongcheng District, Beijing 100050, China
| | - Qing Liang Feng
- Department of Radiology, Linyi Central Hospital, 17 Kangfu Lu Linyi Shandong, 276400, China
| | - Gui Hong Wang
- Center for Neurodegenerative Diseases, Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, 6 Tiantan Xili, Dongcheng District, Beijing 100050, China
| | - Shaofeng Duan
- Division of Nuclear Technology and Applications, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China
| | - Bao Ci Shan
- Division of Nuclear Technology and Applications, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China
| | - Jian Ping Dai
- Neuroimaging center, Department of Radiology, Beijing Tiantan Hospital, Capital Medical University,6 Tiantan Xili, Dongcheng District, Beijing 100050, China.
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16
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Alhilali LM, Delic J, Fakhran S. Differences in Callosal and Forniceal Diffusion between Patients with and without Postconcussive Migraine. AJNR Am J Neuroradiol 2017; 38:691-695. [PMID: 28126745 DOI: 10.3174/ajnr.a5073] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Accepted: 11/16/2016] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Posttraumatic migraines are common after mild traumatic brain injury. The purpose of this study was to determine if a specific axonal injury pattern underlies posttraumatic migraines after mild traumatic brain injury utilizing Tract-Based Spatial Statistics analysis of diffusion tensor imaging. MATERIALS AND METHODS DTI was performed in 58 patients with mild traumatic brain injury with posttraumatic migraines. Controls consisted of 17 patients with mild traumatic brain injury without posttraumatic migraines. Fractional anisotropy and diffusivity maps were generated to measure white matter integrity and were evaluated by using Tract-Based Spatial Statistics regression analysis with a general linear model. DTI findings were correlated with symptom severity, neurocognitive test scores, and time to recovery with the Pearson correlation coefficient. RESULTS Patients with mild traumatic brain injury with posttraumatic migraines were not significantly different from controls in terms of age, sex, type of injury, or neurocognitive test performance. Patients with posttraumatic migraines had higher initial symptom severity (P = .01) than controls. Compared with controls, patients with mild traumatic brain injury with posttraumatic migraines had decreased fractional anisotropy in the corpus callosum (P = .03) and fornix/septohippocampal circuit (P = .045). Injury to the fornix/septohippocampal circuit correlated with decreased visual memory (r = 0.325, P = .01). Injury to corpus callosum trended toward inverse correlation with recovery (r = -0.260, P = .05). CONCLUSIONS Injuries to the corpus callosum and fornix/septohippocampal circuit were seen in patients with mild traumatic brain injury with posttraumatic migraines, with injuries in the fornix/septohippocampal circuit correlating with decreased performance on neurocognitive testing.
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Affiliation(s)
- L M Alhilali
- From the Department of Neuroradiology (L.M.A.), Barrow Neurological Institute, Phoenix, Arizona
| | - J Delic
- Department of Radiology (J.D.), Division of Neuroradiology, University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania
| | - S Fakhran
- East Valley Diagnostic Imaging (S.F.), Banner Health and Hospital System, Mesa, Arizona
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17
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Green AE, Croft RJ, Maller JJ, Fitzgerald PB. White matter correlates of episodic memory encoding and retrieval in schizophrenia. Psychiatry Res Neuroimaging 2016; 254:188-198. [PMID: 27479923 DOI: 10.1016/j.pscychresns.2016.07.002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/18/2015] [Accepted: 07/05/2016] [Indexed: 01/14/2023]
Abstract
Episodic memory (EM) impairments in schizophrenia (SZ) are predictive of functional outcome and are a potential endophenotype of the disorder. The current study investigated the neuroanatomical correlates of EM encoding and retrieval in SZ with structural magnetic resonance and diffusion tensor imaging (DTI) measures in 22 patients with SZ and 22 age- and gender-matched healthy controls. Tract-based Spatial Statistics (TBSS) was used to investigate microstructural alterations in white matter (WM), while FreeSurfer surface-based analysis was used to determine abnormalities in grey matter (GM) and WM volumetrics and cortical thickness. Compared to controls, patients demonstrated GM deficits in temporal and parietal regions and lower fractional anisotropy (FA) of WM in diffuse brain regions. Patients also demonstrated reduced functioning in both encoding and retention of auditory-verbal EM. Among patients but not controls, EM encoding correlated with WM volume in the orbitofrontal cortex and increased radial diffusivity in the fornix, whereas EM retrieval correlated with WM volume in posterior parietal cortex. These findings suggest a differential role for frontal and parietal WM in EM encoding and retrieval processes, while myelin integrity of the fornix may play a specific role in mediating EM encoding processes in SZ.
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Affiliation(s)
- Amity E Green
- Monash Alfred Psychiatry Research Centre, Central Clinical School, Monash University and the Alfred Hospital, Australia.
| | - Rodney J Croft
- Illawarra Health & Medical Research Institute, University of Wollongong, Australia; School of Psychology, University of Wollongong, Australia
| | - Jerome J Maller
- Monash Alfred Psychiatry Research Centre, Central Clinical School, Monash University and the Alfred Hospital, Australia
| | - Paul B Fitzgerald
- Monash Alfred Psychiatry Research Centre, Central Clinical School, Monash University and the Alfred Hospital, Australia
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18
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Baumann PS, Griffa A, Fournier M, Golay P, Ferrari C, Alameda L, Cuenod M, Thiran JP, Hagmann P, Do KQ, Conus P. Impaired fornix-hippocampus integrity is linked to peripheral glutathione peroxidase in early psychosis. Transl Psychiatry 2016; 6:e859. [PMID: 27459724 PMCID: PMC5545707 DOI: 10.1038/tp.2016.117] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/05/2015] [Revised: 03/17/2016] [Accepted: 04/15/2016] [Indexed: 12/19/2022] Open
Abstract
Several lines of evidence implicate the fornix-hippocampus circuit in schizophrenia. In early-phase psychosis, this circuit has not been extensively investigated and the underlying mechanisms affecting the circuit are unknown. The hippocampus and fornix are vulnerable to oxidative stress at peripuberty in a glutathione (GSH)-deficient animal model. The purposes of the current study were to assess the integrity of the fornix-hippocampus circuit in early-psychosis patients (EP), and to study its relationship with peripheral redox markers. Diffusion spectrum imaging and T1-weighted magnetic resonance imaging (MRI) were used to assess the fornix and hippocampus in 42 EP patients compared with 42 gender- and age-matched healthy controls. Generalized fractional anisotropy (gFA) and volumetric properties were used to measure fornix and hippocampal integrity, respectively. Correlation analysis was used to quantify the relationship of gFA in the fornix and hippocampal volume, with blood GSH levels and glutathione peroxidase (GPx) activity. Patients compared with controls exhibited lower gFA in the fornix as well as smaller volume in the hippocampus. In EP, but not in controls, smaller hippocampal volume was associated with high GPx activity. Disruption of the fornix-hippocampus circuit is already present in the early stages of psychosis. Higher blood GPx activity is associated with smaller hippocampal volume, which may support a role of oxidative stress in disease mechanisms.
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Affiliation(s)
- P S Baumann
- Department of Psychiatry, Unit for Research in Schizophrenia, Center for Psychiatric Neuroscience, Centre Hospitalier Universitaire Vaudois, Lausanne University Hospital (CHUV), University of Lausanne, Lausanne, Switzerland
- Department of Psychiatry, Service of General Psychiatry, Centre Hospitalier Universitaire Vaudois, Lausanne University Hospital (CHUV), Lausanne, Switzerland
| | - A Griffa
- Signal Processing Laboratory (LTS5), Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
- Department of Radiology, Lausanne University Hospital (CHUV), University of Lausanne, Lausanne, Switzerland
| | - M Fournier
- Department of Psychiatry, Unit for Research in Schizophrenia, Center for Psychiatric Neuroscience, Centre Hospitalier Universitaire Vaudois, Lausanne University Hospital (CHUV), University of Lausanne, Lausanne, Switzerland
| | - P Golay
- Department of Psychiatry, Service of General Psychiatry, Centre Hospitalier Universitaire Vaudois, Lausanne University Hospital (CHUV), Lausanne, Switzerland
- Service of Community Psychiatry, Department of Psychiatry, Lausanne University Hospital (CHUV), Lausanne, Switzerland
| | - C Ferrari
- Department of Psychiatry, Unit for Research in Schizophrenia, Center for Psychiatric Neuroscience, Centre Hospitalier Universitaire Vaudois, Lausanne University Hospital (CHUV), University of Lausanne, Lausanne, Switzerland
| | - L Alameda
- Department of Psychiatry, Unit for Research in Schizophrenia, Center for Psychiatric Neuroscience, Centre Hospitalier Universitaire Vaudois, Lausanne University Hospital (CHUV), University of Lausanne, Lausanne, Switzerland
- Department of Psychiatry, Service of General Psychiatry, Centre Hospitalier Universitaire Vaudois, Lausanne University Hospital (CHUV), Lausanne, Switzerland
| | - M Cuenod
- Department of Psychiatry, Unit for Research in Schizophrenia, Center for Psychiatric Neuroscience, Centre Hospitalier Universitaire Vaudois, Lausanne University Hospital (CHUV), University of Lausanne, Lausanne, Switzerland
| | - J-P Thiran
- Signal Processing Laboratory (LTS5), Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
- Department of Radiology, Lausanne University Hospital (CHUV), University of Lausanne, Lausanne, Switzerland
| | - P Hagmann
- Signal Processing Laboratory (LTS5), Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
- Department of Radiology, Lausanne University Hospital (CHUV), University of Lausanne, Lausanne, Switzerland
| | - K Q Do
- Department of Psychiatry, Unit for Research in Schizophrenia, Center for Psychiatric Neuroscience, Centre Hospitalier Universitaire Vaudois, Lausanne University Hospital (CHUV), University of Lausanne, Lausanne, Switzerland
| | - P Conus
- Department of Psychiatry, Service of General Psychiatry, Centre Hospitalier Universitaire Vaudois, Lausanne University Hospital (CHUV), Lausanne, Switzerland
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19
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Gajhede Gram M, Gade L, Wogensen E, Mogensen J, Malá H. Equal effects of typical environmental and specific social enrichment on posttraumatic cognitive functioning after fimbria-fornix transection in rats. Brain Res 2015; 1629:182-95. [PMID: 26499260 DOI: 10.1016/j.brainres.2015.10.019] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2015] [Revised: 10/08/2015] [Accepted: 10/12/2015] [Indexed: 12/11/2022]
Abstract
Enriched environment (EE) has been shown to have beneficial effects on cognitive recovery after brain injury. Typical EE comprises three components: (i) enlarged living area providing physical activation, (ii) sensory stimulation, and (iii) social stimulation. The present study assessed the specific contribution of the social stimulation. Animals were randomly divided into groups of (1) a typical EE, (2) pure social enrichment (SE), or (3) standard housing (SH) and subjected to either a sham operation or transection of the fimbria-fornix (FF). The effect of these conditions on acquisition of a delayed alternation task in a T-maze was assessed. The sham control groups were not affected by housing conditions. In the lesioned groups, both typical EE and SE improved the task acquisition, compared to SH. A baseline one-hour activity measurement confirmed an equal level of physical activity in the EE and SE groups. After delayed alternation testing, pharmacological challenges (muscarinergic antagonist scopolamine and dopaminergic antagonist SKF-83566) were used to assess cholinergic and dopaminergic contributions to task solution. Scopolamine led to a marked impairment in all groups. SKF-83566 significantly enhanced the performance of the lesioned group subjected to SE. The results demonstrate that housing in a typical as well as atypical EE can enhance cognitive recovery after mechanical injury to the hippocampus. The scopolamine challenge revealed a cholinergic dependency during task performance in all groups, regardless of lesion and housing conditions. The dopaminergic challenge revealed a difference in the neural substrates mediating recovery in the lesioned groups exposed to different types of housing.
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Affiliation(s)
- Marie Gajhede Gram
- The Unit for Cognitive Neuroscience, Department of Psychology, University of Copenhagen, Oester Farimagsgade 2A, DK-1353 Copenhagen K, Denmark.
| | - Louise Gade
- The Unit for Cognitive Neuroscience, Department of Psychology, University of Copenhagen, Oester Farimagsgade 2A, DK-1353 Copenhagen K, Denmark.
| | - Elise Wogensen
- The Unit for Cognitive Neuroscience, Department of Psychology, University of Copenhagen, Oester Farimagsgade 2A, DK-1353 Copenhagen K, Denmark.
| | - Jesper Mogensen
- The Unit for Cognitive Neuroscience, Department of Psychology, University of Copenhagen, Oester Farimagsgade 2A, DK-1353 Copenhagen K, Denmark.
| | - Hana Malá
- The Unit for Cognitive Neuroscience, Department of Psychology, University of Copenhagen, Oester Farimagsgade 2A, DK-1353 Copenhagen K, Denmark.
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Contarino VE, Bulgheroni S, Savoiardo M, Annunziata S, Aquino D, Riva D, Erbetta A. Constrained spherical deconvolution-based tractography to depict and characterize a case of "hyperplastic fornix dorsalis". Magn Reson Imaging 2014; 32:1428-33. [PMID: 25093633 DOI: 10.1016/j.mri.2014.07.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2014] [Revised: 05/29/2014] [Accepted: 07/25/2014] [Indexed: 11/17/2022]
Abstract
The authors report the relevance of Constrained Spherical Deconvolution (CSD)-based tractography in demonstrating and quantitatively assessing a complex midline structure malformation in a 9-year-old girl with moderate intellectual disability and thickening of corpus callosum (CC) body discovered through conventional MRI (cMRI). Color-encoded fractional anisotropy (FA) maps clearly demonstrated what the cMRI showed as a thicknening of CC: a green, longitudinal bundle running dorsally to the body of CC. A more complex midline maldevelopmental disorder was suspected. CSD-based tractography was performed to virtually dissect the anomalous supracallosal longitudinal bundle (SLB), CC, fornix, anterior commissure (AC) and cingula. In addition, DTI-derived metrics were calculated for each virtually dissected fiber tract. The tractography study evidenced projections of the anomalous SLB in left forceps minor and to parietal regions, and projections of the fornix in right forceps minor. CC virtual dissection showed no gross abnormality, and cingula appeared slightly less extended than normal. The considerable thinning of AC hampered its virtual dissection. DTI-derived metrics suggested alterations in fornix microstructure, attributable to higher fiber density. In investigating white matter, cMRI may not be sufficient in addressing and assessing possible anomalies, while advanced CSD-based tractography and DTI-derived metrics may prove helpful in depicting and characterizing white matter anomalies in developmental disorders.
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Affiliation(s)
| | - Sara Bulgheroni
- Developmental Neurology Division, Fondazione IRCCS Istituto Neurologico C.Besta, Milano, Italy
| | - Mario Savoiardo
- Neuroradiology Department, Fondazione, IRCCS Istituto Neurologico C.Besta, Milano, Italy
| | - Silvia Annunziata
- Developmental Neurology Division, Fondazione IRCCS Istituto Neurologico C.Besta, Milano, Italy
| | - Domenico Aquino
- Neuroradiology Department, Fondazione, IRCCS Istituto Neurologico C.Besta, Milano, Italy
| | - Daria Riva
- Developmental Neurology Division, Fondazione IRCCS Istituto Neurologico C.Besta, Milano, Italy
| | - Alessandra Erbetta
- Neuroradiology Department, Fondazione, IRCCS Istituto Neurologico C.Besta, Milano, Italy
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Canu E, Agosta F, Galantucci S, Chiò A, Riva N, Silani V, Falini A, Comi G, Filippi M. Extramotor damage is associated with cognition in primary lateral sclerosis patients. PLoS One 2013; 8:e82017. [PMID: 24349172 PMCID: PMC3857796 DOI: 10.1371/journal.pone.0082017] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2013] [Accepted: 10/29/2013] [Indexed: 11/29/2022] Open
Abstract
Objectives This is a cross-sectional study aimed at investigating cognitive performances in patients with primary lateral sclerosis (PLS) and using diffusion tensor (DT) magnetic resonance imaging (MRI) to determine the topographical distribution of microstructural white matter (WM) damage in patients with or without cognitive deficits. Methods DT MRI scans were obtained from 21 PLS patients and 35 age- and sex-matched healthy controls. All PLS patients underwent a comprehensive neuropsychological battery. Tract-based-spatial-statistics (TBSS) was used to perform a whole-brain voxel-wise analysis of fractional anisotropy (FA), axial, radial (radD) and mean diffusivity (MD). Results Ten PLS patients had abnormal scores in at least one neuropsychological test (PLS with cognitive deficits, PLS-cd). Compared with healthy controls and cognitively unimpaired PLS patients (PLS-cu), PLS-cd cases showed decreased FA and increased MD and radD in the corticospinal tract (CST), corpus callosum, brainstem, anterior limb of internal capsule, superior and inferior longitudinal fasciculi, fornix, thalamic radiations, and parietal lobes, bilaterally. Compared with healthy controls, PLS-cd patients showed further decreased FA and increased radD in the cerebellar WM, bilaterally. Compared with controls, PLS-cu patients showed decreased FA in the mid-body of corpus callosum. In PLS, executive and language test scores correlated with WM damage. Conclusions This is the first study evaluating the relationship between cognitive performance and WM tract damage in PLS patients. PLS can be associated with a multi-domain cognitive impairment. WM damage to interhemispheric, limbic and major associative WM tracts seem to be the structural correlate of cognitive abnormalities in these patients.
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Affiliation(s)
- Elisa Canu
- Neuroimaging Research Unit, Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy
| | - Federica Agosta
- Neuroimaging Research Unit, Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy
| | - Sebastiano Galantucci
- Neuroimaging Research Unit, Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy
| | - Adriano Chiò
- ‘Rita Levi Montalcini’ Department of Neuroscience, University of Torino, Torino, Italy
| | - Nilo Riva
- Department of Neurology, Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy
| | - Vincenzo Silani
- Department of Neurology and Laboratory of Neuroscience, IRCCS Istituto Auxologico Italiano - Department of Pathophysiology and Tranplantation, “Dino Ferrari” Center, Università degli Studi di Milano, Milan, Italy
| | - Andrea Falini
- Department of Neuroradiology, CERMAC, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy
| | - Giancarlo Comi
- Department of Neurology, Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy
| | - Massimo Filippi
- Neuroimaging Research Unit, Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy
- Department of Neurology, Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy
- * E-mail:
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Dineen RA, Bradshaw CM, Constantinescu CS, Auer DP. Extra-hippocampal subcortical limbic involvement predicts episodic recall performance in multiple sclerosis. PLoS One 2012; 7:e44942. [PMID: 23056187 PMCID: PMC3466267 DOI: 10.1371/journal.pone.0044942] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2012] [Accepted: 08/15/2012] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND Episodic memory impairment is a common but poorly-understood phenomenon in multiple sclerosis (MS). We aim to establish the relative contributions of reduced integrity of components of the extended hippocampal-diencephalic system to memory performance in MS patients using quantitative neuroimaging. METHODOLOGY/PRINCIPAL FINDINGS 34 patients with relapsing-remitting MS and 24 healthy age-matched controls underwent 3 T MRI including diffusion tensor imaging and 3-D T1-weighted volume acquisition. Manual fornix regions-of-interest were used to derive fornix fractional anisotropy (FA). Normalized hippocampal, mammillary body and thalamic volumes were derived by manual segmentation. MS subjects underwent visual recall, verbal recall, verbal recognition and verbal fluency assessment. Significant differences between MS patients and controls were found for fornix FA (0.38 vs. 0.46, means adjusted for age and fornix volume, P<.0005) and mammillary body volumes (age-adjusted means 0.114 ml vs. 0.126 ml, P<.023). Multivariate regression analysis identified fornix FA and mammillary bodies as predictor of visual recall (R(2) = .31, P = .003, P = .006), and thalamic volume as predictive of verbal recall (R(2) = .37, P<.0005). No limbic measures predicted verbal recognition or verbal fluency. CONCLUSIONS/SIGNIFICANCE These findings indicate that structural and ultrastructural alterations in subcortical limbic components beyond the hippocampus predict performance of episodic recall in MS patients with mild memory dysfunction.
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Affiliation(s)
- Robert A Dineen
- Division of Radiological and Imaging Sciences, University of Nottingham, Nottingham, United Kingdom.
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van Bruggen T, Stieltjes B, Thomann PA, Parzer P, Meinzer HP, Fritzsche KH. Do Alzheimer-specific microstructural changes in mild cognitive impairment predict conversion? Psychiatry Res 2012; 203:184-93. [PMID: 22947309 DOI: 10.1016/j.pscychresns.2011.12.003] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/12/2011] [Revised: 11/24/2011] [Accepted: 12/08/2011] [Indexed: 01/18/2023]
Abstract
Diffusion tensor imaging (DTI) is a magnetic resonance imaging (MRI) technique that provides information on the fiber architecture of the brain by measuring water diffusion. Prior work has shown that neuronal degeneration in Alzheimer's disease (AD) and mild cognitive impairment (MCI) alters this architecture. Since the conversion rate to AD is much higher for MCI patients than for normal healthy people, it is important to identify biomarkers with a predictive value on this conversion. In this study, we applied tract-based spatial statistics (TBSS) on datasets of 15 healthy controls, 15 AD patients, and 17 MCI patients. Of these MCI patients eight remained stable, whereas nine developed AD within the first 12-18 months of follow-up investigations. Analysis using TBSS combined with a maximum likelihood regression with random effects of the fornix, the corpus callosum, and the cingulum identified significant differences between these two types of MCI patients in fractional anisotropy (FA) and radial diffusivity (DR). Thus, DTI reveals Alzheimer-specific changes in those MCI subjects that later convert, although they were clinically identical to the other MCI-patients at the time the data were acquired. This finding could lead to early identification of AD and thereby aid early clinical intervention.
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Affiliation(s)
- Thomas van Bruggen
- Division of Medical and Biological Informatics, German Cancer Research Center, Heidelberg, Germany
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Hattori T, Sato R, Aoki S, Yuasa T, Mizusawa H. Different patterns of fornix damage in idiopathic normal pressure hydrocephalus and Alzheimer disease. AJNR Am J Neuroradiol 2012; 33:274-9. [PMID: 22081679 PMCID: PMC7964782 DOI: 10.3174/ajnr.a2780] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2011] [Accepted: 07/13/2011] [Indexed: 12/13/2022]
Abstract
BACKGROUND AND PURPOSE The fornix contains efferent fibers of the hippocampus and is in close contact with the corpus callosum. Part of the fornix is directly attached to the corpus callosum, and another part is suspended from the corpus callosum via the septum pellucidum. DTI can be used to evaluate the morphology and microstructural integrity of the fornix. We examined the pattern of fornix damage in patients with iNPH or AD. MATERIALS AND METHODS We enrolled 22 patients with iNPH, 20 with AD, and 20 healthy controls. DTI data were obtained. The morphology (volume, length, and mean cross-sectional area) and FA values of the fornix were evaluated by using tract-specific analysis and compared among groups. RESULTS The volume, cross-sectional area, and FA value of the fornix were significantly smaller in patients with iNPH than in controls, whereas the length was significantly greater. In patients with AD, the volume, mean cross-sectional area, and FA value of the fornix were significantly smaller than those in controls, whereas the length was not altered. The fornix was significantly longer in patients with iNPH than in patients with AD, whereas the volume and cross-sectional areas were significantly smaller. CONCLUSIONS Our results suggest that the different pathogeneses of these diseases lead to fornix damage through different mechanisms: through mechanical stretching due to lateral ventricular enlargement and corpus callosum deformation in patients with iNPH, and through degeneration secondary to hippocampal atrophy in patients with AD.
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Affiliation(s)
- T Hattori
- Department of Neurology and Neurological Sciences, Graduate School, Tokyo Medical and Dental University, Tokyo, Japan.
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Abstract
Limbic circuitry disruptions have been implicated in the psychopathology and cognitive deficits of schizophrenia, which may involve white matter disruptions of the major tracts of the limbic system, including the fornix and the cingulum. Our study aimed to investigate regionally specific abnormalities of the fornix and cingulum in schizophrenia using diffusion tensor imaging (DTI). We determined the fractional anisotropy (FA), radial diffusivity (RD), and axial diffusivity (AD) profiles along the fornix and cingulum tracts using a fibertracking technique and a brain mapping algorithm, the large deformation diffeomorphic metric mapping (LDDMM), in the DTI scans of 33 patients with schizophrenia and 31 age-, gender-, and handedness-matched healthy controls. We found that patients with schizophrenia showed reduction in FA and increase in RD in bilateral fornix, and increase in RD in left anterior cingulum when compared to healthy controls. In addition, tract-based analysis revealed specific loci of these white matter differences in schizophrenia, that is, FA reductions and AD and RD increases occur in the region of the left fornix further from the hippocampus, FA reductions and RD increases occur in the rostral portion of the left anterior cingulum, and RD and AD increases occur in the anterior segment of the left middle cingulum. In patients with schizophrenia, decreased FA in the specific loci of the left fornix and increased AD in the right cingulum adjoining the hippocampus correlated with greater severity of psychotic symptoms. These findings support precise disruptions of limbic-cortical integrity in schizophrenia and disruption of these structural networks may contribute towards the neural basis underlying the syndrome of schizophrenia and clinical symptomatology.
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Affiliation(s)
| | - Anqi Qiu
- Division of Bioengineering, National University of Singapore, Singapore, Singapore
- Clinical Imaging Research Center, National University of Singapore, Singapore, Singapore
- Singapore Institute for Clinical Sciences, the Agency for Science, Technology and Research, Singapore, Singapore
- * E-mail:
| | - Kang Sim
- Research Department, Institute of Mental Health, Singapore, Singapore
- Department of General Psychiatry, Institute of Mental Health, Singapore, Singapore
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Foroughi M, Hendson G, Sargent MA, Steinbok P. Spontaneous regression of septum pellucidum/forniceal pilocytic astrocytomas--possible role of Cannabis inhalation. Childs Nerv Syst 2011; 27:671-9. [PMID: 21336992 DOI: 10.1007/s00381-011-1410-4] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/14/2011] [Accepted: 01/27/2011] [Indexed: 11/26/2022]
Abstract
INTRODUCTION Spontaneous regression of pilocytic astrocytoma after incomplete resection is well recognized, especially for cerebellar and optic pathway tumors, and tumors associated with Neurofibromatosis type-1 (NF1). The purpose of this report is to document spontaneous regression of pilocytic astrocytomas of the septum pellucidum and to discuss the possible role of cannabis in promoting regression. CASE REPORT We report two children with septum pellucidum/forniceal pilocytic astrocytoma (PA) tumors in the absence of NF-1, who underwent craniotomy and subtotal excision, leaving behind a small residual in each case. During Magnetic Resonance Imaging (MRI) surveillance in the first three years, one case was dormant and the other showed slight increase in size, followed by clear regression of both residual tumors over the following 3-year period. Neither patient received any conventional adjuvant treatment. The tumors regressed over the same period of time that cannabis was consumed via inhalation, raising the possibility that the cannabis played a role in the tumor regression. CONCLUSION We advise caution against instituting adjuvant therapy or further aggressive surgery for small residual PAs, especially in eloquent locations, even if there appears to be slight progression, since regression may occur later. Further research may be appropriate to elucidate the increasingly recognized effect of cannabis/cannabinoids on gliomas.
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Affiliation(s)
- Mansoor Foroughi
- Division of Pediatric Neurosurgery, Department of Surgery, BC Children's Hospital, 4480 Oak Street, Vancouver, BC, Canada, V6H 3V4
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27
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Abstract
The effects of age on nerve fibers and neuroglial cells in the fornix were examined in 25 rhesus monkeys between 4 and 33 years of age. There is no age-related change in the cross-sectional area of the fornix, but there is a significant loss of myelinated nerve fibers. The loss of myelinated nerve fibers is accompanied by a significant increase in the numbers of nerve fibers that show degeneration of their axons and alterations in myelin sheaths. Aging also brings about an increase in the frequency of profiles of paranodes, indicating that some of the nerve fibers are being remyelinated. Aging also affects neuroglial cells. Each type shows inclusions in their perikarya, and in the case of astrocytes and microglial cells some of these inclusions are phagocytosed myelin. Numbers of astrocytes and microglial cells do not appear to increase with age, but there is a 20% increase in oligodendrocytes. When correlations with cognitive impairments displayed by individual monkeys are examined, the decreased packing density of nerve fibers and the increasing frequency of nerve fibers with degenerating axons and of nerve fibers with altered myelin sheaths all correlate with increasing cognitive impairment. It is suggested that these correlations result from some disconnection of the hippocampus from the thalamus, septal nuclei, and medial frontal cortex and from reductions in the conduction velocity brought about by the shorter internodal lengths of remyelinated nerve fibers in the fornix.
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Affiliation(s)
- Alan Peters
- Department of Anatomy and Neurobiology, Boston University School of Medicine, Boston, Massachusetts 02118, USA.
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Affiliation(s)
- Ji Heon Hong
- Department of Physical Medicine and Rehabilitation, College of Medicine, Yeungnam University, Taegu, Republic of Korea
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Abstract
Congenital central hypoventilation syndrome (CCHS) is accompanied by reduced ventilatory sensitivity to CO2 and O2, respiratory drive failure during sleep, impaired autonomic, fluid, and food absorption regulation, and affective and cognitive deficits, including memory deficiencies. The deficits likely derive from neural injury, reflected as structural damage and impaired functional brain responses to ventilatory and autonomic challenges. Brain structures playing essential memory roles, including the hippocampus and anterior thalamus, are damaged in CCHS. Other memory formation circuitry, the fornix and mammillary bodies, have not been evaluated. We collected two high-resolution T1-weighted image series from 14 CCHS and 31 control subjects, using a 3.0-Tesla magnetic resonance imaging scanner. Image series were averaged and reoriented to a standard template; areas containing the mammillary bodies and fornices were over sampled, and body volumes and fornix cross-sectional areas were calculated and compared between groups. Both left and right mammillary body volumes and fornix cross-sectional areas were significantly reduced in CCHS over control subjects, controlling for age, gender, and intracranial volume. Damage to these structures may contribute to memory deficiencies found in CCHS. Hypoxic processes, together with diminished neuroprotection from micronutrient deficiencies secondary to fluid and dietary absorption issues, may contribute to the injury.
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Affiliation(s)
- Rajesh Kumar
- Department of Neurobiology, University of California at Los Angeles, Los Angeles, California 90095, USA
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Denby CE, Vann SD, Tsivilis D, Aggleton JP, Montaldi D, Roberts N, Mayes AR. The frequency and extent of mammillary body atrophy associated with surgical removal of a colloid cyst. AJNR Am J Neuroradiol 2009; 30:736-43. [PMID: 19164441 DOI: 10.3174/ajnr.a1424] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
BACKGROUND AND PURPOSE Patients who have had a colloid cyst removed from the third ventricle sometimes experience some difficulty with day-to-day memory. This study provided quantitative MR imaging volume measures of 1 structure potentially responsible for mnemonic problems, the mammillary bodies. Additional volume estimates in structures connected to the mammillary bodies sought to determine the specificity of any atrophy. MATERIALS AND METHODS Volume estimates of the mammillary bodies were performed on 38 patients after surgical removal of colloid cysts and 20 control subjects by the application of stereologic volume-estimation techniques. For the mammillary body measures, 2 groups of MR images were assessed (0.8- and 1.0-mm section thickness) to compare the sensitivity of each imaging sequence for detecting any atrophy. Other structures associated with memory processes, such as the hippocampus and fornix, were also assessed quantitatively to determine whether there was a correlation between mammillary body damage and atrophy in connecting structures. RESULTS Our investigations established the superiority of 0.8-mm-volume scans over standard isotropic 1.0-mm-thick-volume scans for mammillary body assessments. Comparisons with 20 age-matched controls revealed that patients with colloid cysts frequently showed significant mammillary body atrophy (mean volume of colloid cysts, 0.037 cm(3) right and 0.038 cm(3) left; control subjects, 0.069 cm(3) right and 0.067 cm(3) left). In fact, every patient had a mammillary body volume below the control mean, and the majority of patients had a volume decrease of >1 SD (82% right, 74% left). Mammillary body volumes correlated with fornix volumes in the same patient group. CONCLUSIONS Our results reveal the frequent presence of mammillary body atrophy in patients with surgical removal of colloid cysts and indicate that this atrophy is partly due to a loss of temporal lobe projections in the fornix.
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Affiliation(s)
- C E Denby
- School of Psychological Sciences, Manchester, England.
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Brisch R, Bernstein HG, Stauch R, Dobrowolny H, Krell D, Truebner K, Meyer-Lotz G, Bielau H, Steiner J, Kropf S, Gos T, Danos P, Bogerts B. The volumes of the fornix in schizophrenia and affective disorders: a post-mortem study. Psychiatry Res 2008; 164:265-73. [PMID: 19022630 DOI: 10.1016/j.pscychresns.2007.12.007] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/05/2007] [Revised: 09/22/2007] [Accepted: 12/22/2007] [Indexed: 11/19/2022]
Abstract
Structural and functional pathology of limbic structures including the hippocampus are frequently replicated in schizophrenia. Although the fornix is the main afferent system of the hippocampus to the septal nuclei and the hypothalamus (especially the mammillary bodies), relatively few studies have investigated structural changes of the fornix in schizophrenia. We measured the volume of the fornix in post-mortem brains in 19 patients with schizophrenia, 9 patients with bipolar disorder, 7 patients with unipolar depression, and 14 control subjects by planimetry of serial sections. The volumes, the mean cross-sectional areas, and the anterior to posterior distances of the fornix did not differ among patients with schizophrenia, bipolar disorder, unipolar depression, and control subjects. No lateralization existed between the right and the left fornices in among patients in the diagnostic groups and the control subjects. The fornix does not show morphometrical abnormalities in patients with schizophrenia, bipolar disorder and unipolar depression compared with control subjects, which might indicate that the fornix is not a primary focus of structural changes in these diseases.
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Affiliation(s)
- Ralf Brisch
- Department of Psychiatry, Otto-von-Guericke-University of Magdeburg, Leipziger Str. 44, D-39120 Magdeburg, Germany.
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32
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Takei K, Yamasue H, Abe O, Yamada H, Inoue H, Suga M, Sekita K, Sasaki H, Rogers M, Aoki S, Kasai K. Disrupted integrity of the fornix is associated with impaired memory organization in schizophrenia. Schizophr Res 2008; 103:52-61. [PMID: 18442897 DOI: 10.1016/j.schres.2008.03.008] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/27/2007] [Revised: 02/23/2008] [Accepted: 03/06/2008] [Indexed: 11/30/2022]
Abstract
BACKGROUND The fornix is a major projection of the hippocampus to and from other brain regions. A previous diffusion tensor imaging (DTI) study has reported disrupted integrity of the fornix in patients with schizophrenia. However, functional significance of the DTI abnormalities of the fornix in schizophrenia has not been fully studied yet. We investigated an association between DTI abnormalities of the fornix and impairment of memory organization in schizophrenia. METHODS Thirty-one patients with schizophrenia and 65 age- and gender-matched healthy controls underwent DTI, and fractional anisotropy (FA) and mean diffusivity (MD) were measured in cross-sections of fornix tractography. In addition, all of the patients and 32 controls performed a verbal learning task specialized for evaluating memory organization, the verbal memory subscale of the Wechsler Memory Scale-Revised, the category- and letter fluency tests, and the Japanese version of National Adult Reading Test. RESULTS Statistically significant reduction of FA and increase of MD were found in the fornix of patients with schizophrenia compared with controls with no significant lateralization. A significant patients-specific correlation was found between increased MD in the left fornix and lower scores on utilization of semantic organization in the verbal learning task. In addition, increased MD in the right fornix showed a patients-specific association with poorer performance on the category fluency test, which indexes organization of long-term semantic memory. These patients-specific correlations, however, were not statistically lateralized to either hemisphere. CONCLUSIONS These results indicate that disrupted integrity of the fornix contributes to impaired memory organization in schizophrenia.
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Affiliation(s)
- Kunio Takei
- Department of Neuropsychiatry, Graduate School of Medicine, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8655, Japan.
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Robertson DAF, Beattie JE, Reid IC, Balfour DJK. Influence of 5,7-dihydroxytryptamine lesions of the rat fornix-fimbria and cingulum bundles on spontaneous activity in an aversive maze. J Psychopharmacol 2008; 22:285-9. [PMID: 18208913 DOI: 10.1177/0269881107083841] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Exposure to aversive environmental stimuli stimulates the serotonergic neurones that project to the forebrain and inhibit spontaneous activity when studied in a simple maze. This study explored the putative role of the principal 5-hydroxytryptamine (5-HT) neurones that project to the hippocampus from the median raphe nucleus in this response to an aversive environment by lesioning the 5-HT fibres that project through the fornix/fimbria and cingulum bundles. The effects of the lesions were investigated in independent groups of animals tested in an enclosed four-arm maze and a more aversive elevated maze of the same dimensions composed entirely of four open arms. The rats were significantly less active in the open maze, the principal effect of maze design being observed during the first 5 min sub-trial of a 15 min trial. This response to the more aversive environment was totally abolished by the lesion. It is concluded that exposure to an explicitly aversive environment elicits a brief stimulation of the 5-HT neurones that project to the hippocampus from the median raphe nucleus and that this stimulation inhibits the initial burst of exploratory activity that is observed in animals placed in a less aversive novel environment.
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Affiliation(s)
- D A F Robertson
- Section of Psychiatry, Division of Pathology and Neuroscience, University of Dundee Medical School, Ninewells Hospital, Dundee, UK.
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Abstract
Studies of patients with major depression disorder (MDD) have revealed reduced hippocampal volumes, but findings have been inconsistent due to sample and measurement differences. The current study sought to measure this structure in a large sample of MDD and control subjects, using a strict measurement protocol, in order to elucidate morphological-specific volumetric differences. Forty-five subjects with treatment-resistant MDD and 26 controls underwent psychiatric assessments and brain magnetic resonance imaging (MRI). The findings of this study indicate that (1) MDD results in reduced hippocampal volume, particularly in the tail section, (2) region of interest (ROI) estimation protocols and sample characteristics may help explain volumetric differences between previous MDD studies, and (3) specific ROI atrophy in treatment-resistant depression is influenced by sex.
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Affiliation(s)
- Jerome J Maller
- Department of Psychological Medicine, Alfred Psychiatry Research Centre, The Alfred & Monash University, Melbourne Victoria, Australia.
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35
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Abstract
BACKGROUND Depressed mood has been associated with decreased white matter and reduced hippocampal volumes. However, the relationship between brain structure and mood may be unique among adolescents who use marijuana heavily. The goal of this study was to examine the relationship between white matter and hippocampal volumes and depressive symptoms among adolescent marijuana users and controls. METHODS Data were collected from marijuana users (n = 16) and demographically similar controls (n = 16) aged 16-18. Extensive exclusionary criteria included psychiatric and neurologic disorders, including major depression. Substance use, mood, and anatomical measures were collected after 28 days of monitored abstinence. RESULTS Marijuana (MJ) users demonstrated more depressive symptoms than controls (p < .05). MJ use (beta = .42, p < .005) and smaller white matter volume (beta = -.34, p < .03) each predicted higher levels of depressive symptoms on the Hamilton Depression Rating Scale. MJ use interacted with white matter volume (beta = -.55, p < .03) in predicting depression scores on the Beck Depression Inventory: among MJ users, but not controls, white matter volume was negatively associated with depressive symptoms. CONCLUSIONS Marijuana use and white matter volume were additive and interactive in predicting depressive symptoms among adolescents. Subtle neurodevelopmental white matter abnormalities may disrupt the connections between areas involved in mood regulation.
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Ringman JM, O'Neill J, Geschwind D, Medina L, Apostolova LG, Rodriguez Y, Schaffer B, Varpetian A, Tseng B, Ortiz F, Fitten J, Cummings JL, Bartzokis G. Diffusion tensor imaging in preclinical and presymptomatic carriers of familial Alzheimer's disease mutations. Brain 2007; 130:1767-76. [PMID: 17522104 DOI: 10.1093/brain/awm102] [Citation(s) in RCA: 189] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Measures are needed that identify persons that will develop Alzheimer's disease in order to target them for preventative interventions. There is evidence from animal, pathological and imaging studies that disruption of white matter occurs in the course of Alzheimer's disease and may be an early event. Prior studies have suggested that late-myelinating regions or white matter connecting limbic structures are particularly susceptible to degradation. Persons destined to develop the disease by virtue of fully penetrant genetic alterations (familial Alzheimer's disease or FAD) provide a model in which early and even presymptomatic changes of the disease may be identified. In this study we performed diffusion tensor imaging (DTI) on 2 demented and 21 subjects at-risk for inheriting an FAD mutation. We compared global and localized fractional anisotropy (FA) measures in white matter between FAD mutation carriers and non-carriers in the preclinical (clinical dementia rating <1, n = 20) and presymptomatic (clinical dementia rating = 0, n = 15) stages of the disease. There were no significant differences between mutation carriers and non-carriers with regard to absolute age, age relative to the typical age of disease diagnosis in their family, gender or Mini-Mental Status Examination Score. Among preclinical FAD mutation carriers (n = 12), mean whole brain white-matter FA (P = 0.045), FA of the columns of the fornix (P = 0.012), area of the perforant pathways bilaterally (right side: P = 0.028, left side: P = 0.027) and left orbitofrontal lobe (P = 0.024) were decreased relative to that of non-carriers (n = 8). We also found that FA in the columns of the fornix (P = 0.008) and left orbitofrontal lobe white matter (P = 0.045) were decreased in the eight presymptomatic mutation carriers compared to seven non-carriers. Logistic regression demonstrated that FA of the columns of the fornix was a better predictor of mutation status than was cross-sectional area of the fornix, global mean white-matter FA and left frontal lobe white-matter FA. In a linear regression analysis, white-matter volume (P = 0.002), hippocampal volume (P = 0.023) and mutation status (P = 0.032) significantly predicted fornix FA. We conclude that FA is decreased in the white matter in preclinical and even presymptomatic FAD mutation carriers, particularly in the late-myelinating tracts connecting limbic structures. Decreased FA in of the columns of the fornix is particularly robust in early FAD and may provide a biomarker for early disease in sporadic Alzheimer's disease.
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Affiliation(s)
- John M Ringman
- UCLA Department of Neurology, Alzheimer's Disease Research Center, 10911 Weyburn Ave, Suite 200, Los Angeles, CA 90095-7226, USA.
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Muller C, Herberth H, Cosquer B, Kelche C, Cassel JC, Schimchowitsch S. Structural and functional recovery elicited by combined putrescine and aminoguanidine treatment after aspirative lesion of the fimbria-fornix and overlying cortex in the adult rat. Eur J Neurosci 2007; 25:1949-60. [PMID: 17439484 DOI: 10.1111/j.1460-9568.2007.05474.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Damage to the adult CNS often causes permanent deficits. Based on a lesion model of septohippocampal pathway aspiration in the rat, we attempted to promote neuronal cell survival and post-traumatic recovery by using a pharmacological treatment combining aminoguanidine and putrescine (AGP). The functional recovery was followed over 15 weeks before morphological analysis. AGP treatment produced a persistent attenuation (approximately 50%) of the lesion-induced hyperactivity, a reduction (approximately 60%) in the sensorimotor impairments and an improved performance in the water-maze task which did not, however, rely upon improved memory capabilities. AGP weakened the lesion-induced decrease in ChAT-positive neurons in the medial septum and the extent of thalamic retrograde necrosis (by approximately 30% in each case) and resulted in a partial cholinergic reinnervation of the dentate gyrus. These promising results support the idea that coadministration of putrescine and aminoguanidine might become a potent way to foster structural and functional recovery (or compensation) in the adult mammalian CNS after injury.
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Affiliation(s)
- Christophe Muller
- Laboratoire de Neurosciences Comportementales et Cognitives, LINC UMR 7191, GDR 2905 CNRS, IFR 37, 67000 Strasbourg, France
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Copenhaver BR, Rabin LA, Saykin AJ, Roth RM, Wishart HA, Flashman LA, Santulli RB, McHugh TL, Mamourian AC. The fornix and mammillary bodies in older adults with Alzheimer's disease, mild cognitive impairment, and cognitive complaints: a volumetric MRI study. Psychiatry Res 2006; 147:93-103. [PMID: 16920336 DOI: 10.1016/j.pscychresns.2006.01.015] [Citation(s) in RCA: 85] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/13/2005] [Revised: 01/21/2006] [Accepted: 01/29/2006] [Indexed: 10/24/2022]
Abstract
The fornix and mammillary bodies are important limbic structures that have not been systematically investigated in the earliest stages of preclinical dementia. The present study examined volumetric changes in the fornix and mammillary bodies and improved previously established tracing guidelines to increase reliability and provide more comprehensive measurements. Volumetric measurements were made in euthymic older adults, including 16 patients with mild Alzheimer's disease (AD), 20 patients with amnestic mild cognitive impairment (MCI), 20 individuals with cognitive complaints (CC) but normal neuropsychological test performance, and 20 demographically matched healthy controls (HC). Structural magnetic resonance imaging included a T1-weighted 1.5-mm coronal volume, acquired on a GE 1.5T LX scanner. After adjustment for total intracranial volume (ICV), significant volume reductions were observed in the fornix and mammillary bodies in patients with AD as compared with HC, CC, and MCI participants. No volume differences were seen between the HC, CC, and MCI groups. Study findings are consistent with previous research showing volume decreases of the fornix and mammillary bodies in AD, and provide new data on the relative preservation of these structures in preclinical disease stages. Results suggest that atrophy of the fornix and mammillary bodies becomes apparent at the point of conversion from MCI to AD. Longitudinal assessments are needed to delineate the time course and extent of the observed volumetric changes.
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Bustamante J, Lopera F. [Tumour of the corpus callosum: the association between interhemispheric disconnection and an anterograde amnesia syndrome]. Rev Neurol 2006; 43:207-12. [PMID: 16883509] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
INTRODUCTION Sperry, or interhemispheric disconnection, syndrome was reported in patients who had undergone surgical section of the corpus callosum carried out in an attempt to control medication-resistant epilepsy. It has occasionally been linked to tumours of the corpus callosum and, although even more rarely, it has also been associated to an amnesic syndrome. In this paper we report the anatomical and neuropsychological findings in a patient with interhemispheric disconnection syndrome associated to a hippocampal-type amnesic syndrome, caused by a tumour in the splenius of the corpus callosum that extended into the fornix. CASE REPORT A 52-year-old white male who visited because of loss of memory; on admission to hospital the physical examination revealed a certain degree of asomatognosia with regard to the left-hand side of the body. An axial tomography brain scan showed a dense central lesion in the brain that extended laterally and occluded the body of both lateral ventricles. A biopsy study revealed an undifferentiated astrocytoma that affected the corpus callosum and the fornix. CONCLUSIONS Sperry, or interhemispheric disconnection, syndrome produced by a tumour in the splenius of the corpus callosum is very likely to course with an amnesic syndrome due to disconnection caused by destruction of the fornix. This association, which characterised our patient's clinical picture, has only previously been described in three cases.
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Affiliation(s)
- J Bustamante
- Universidad de Antioquia, Facultad de Medicina, Grupo de Neurociencias, Medellin, Colombia
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Kuroki N, Kubicki M, Nestor PG, Salisbury DF, Park HJ, Levitt JJ, Woolston S, Frumin M, Niznikiewicz M, Westin CF, Maier SE, McCarley RW, Shenton ME. Fornix integrity and hippocampal volume in male schizophrenic patients. Biol Psychiatry 2006; 60:22-31. [PMID: 16406249 PMCID: PMC2768597 DOI: 10.1016/j.biopsych.2005.09.021] [Citation(s) in RCA: 114] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/09/2004] [Revised: 08/22/2005] [Accepted: 09/30/2005] [Indexed: 11/19/2022]
Abstract
BACKGROUND The hippocampus has been shown to be abnormal in schizophrenia. The fornix is one of the main fiber tracts connecting the hippocampus with other brain regions. Few studies have evaluated the fornix in schizophrenia, however. A focus on fornix abnormalities and their association with hippocampal abnormalities might figure importantly in our understanding of the pathophysiology of schizophrenia. METHODS Line-scan diffusion tensor imaging (DTI) was used to evaluate diffusion in the fornix in 24 male patients with chronic schizophrenia and 31 male control subjects. Maps of fractional anisotropy (FA) and mean diffusivity (D(m)), which are indices sensitive to white-matter integrity, were generated to quantify diffusion within the fornix. We used high spatial resolution magnetic resonance imaging (MRI) to measure hippocampal volume. RESULTS FA and cross-sectional area of the fornix were significantly reduced in patients compared with control subjects. D(m) was significantly increased, whereas hippocampal volume was bilaterally reduced in patients. Reduced hippocampal volume was correlated with increased mean D(m) and reduced cross-sectional area of the fornix for patients. Patients also showed a significant correlation between reduced scores on neuropsychologic measures of declarative-episodic memory and reduced hippocampal volumes. CONCLUSIONS These findings demonstrate a disruption in fornix integrity in patients with schizophrenia.
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Affiliation(s)
- Noriomi Kuroki
- Clinical Neuroscience Division, Laboratory of Neuroscience, Department of Psychiatry, Boston VA Healthcare System, Brockton Division, and Harvard Medical School, Brockton, Massachusetts, USA
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Nakayama N, Okumura A, Shinoda J, Yasokawa YT, Miwa K, Yoshimura SI, Iwama T. Evidence for white matter disruption in traumatic brain injury without macroscopic lesions. J Neurol Neurosurg Psychiatry 2006; 77:850-5. [PMID: 16574734 PMCID: PMC2117497 DOI: 10.1136/jnnp.2005.077875] [Citation(s) in RCA: 162] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
BACKGROUND Non-missile traumatic brain injury (nmTBI) without macroscopically detectable lesions often results in cognitive impairments that negatively affect daily life. AIM To identify abnormal white matter projections in patients with nmTBI with cognitive impairments using diffusion tensor magnetic resonance imaging (DTI). METHODS DTI scans of healthy controls were compared with those of 23 patients with nmTBI who manifested cognitive impairments but no obvious neuroradiological lesions. DTI was comprised of fractional anisotropy analysis, which included voxel-based analysis and confirmatory study using regions of interest (ROI) techniques, and magnetic resonance tractography of the corpus callosum and fornix. RESULTS A decline in fractional anisotropy around the genu, stem and splenium of the corpus callosum was shown by voxel-based analysis. Fractional anisotropy values of the genu (0.47), stem (0.48), and splenium of the corpus callosum (0.52), and the column of the fornix (0.51) were lower in patients with nmTBI than in healthy controls (0.58, 0.61, 0.62 and 0.61, respectively) according to the confirmatory study of ROIs. The white matter architecture in the corpus callosum and fornix of patients with nmTBI were seen to be coarser than in the controls in the individual magnetic resonance tractography. CONCLUSIONS Disruption of the corpus callosum and fornix in patients with nmTBI without macroscopically detectable lesions is shown. DTI is sensitive enough to detect abnormal neural fibres related to cognitive dysfunction after nmTBI.
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Affiliation(s)
- N Nakayama
- Chubu Medical Center for Prolonged Traumatic Brain Dysfunction, Kizawa Memorial Hospital, Minokamo City, Gifu, Japan.
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Turner SJ, Sharma V, Hunter PA. Giant fornix syndrome: a recently described cause of chronic purulent conjunctivitis and severe ocular surface inflammation, with a new diagnostic sign on CT. Eye (Lond) 2006; 20:1481-3. [PMID: 16732218 DOI: 10.1038/sj.eye.6702370] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
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Fletcher BR, Calhoun ME, Rapp PR, Shapiro ML. Fornix lesions decouple the induction of hippocampal arc transcription from behavior but not plasticity. J Neurosci 2006; 26:1507-15. [PMID: 16452674 PMCID: PMC6675482 DOI: 10.1523/jneurosci.4441-05.2006] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The immediate-early gene (IEG) Arc is transcribed after behavioral and physiological treatments that induce synaptic plasticity and is implicated in memory consolidation. The relative contributions of neuronal activity and learning-related plasticity to the behavioral induction of Arc remain to be defined. To differentiate the contributions of each, we assessed the induction of Arc transcription in rats with fornix lesions that impair hippocampal learning yet leave cortical connectivity and neuronal firing essentially intact. Arc expression was assessed after exploration of novel environments and performance of a novel water maze task during which normal rats learned the spatial location of an escape platform. During the same task, rats with fornix lesions learned to approach a visible platform but did not learn its spatial location. Rats with fornix lesions had normal baseline levels of hippocampal Arc mRNA, but unlike normal rats, expression was not increased in response to water maze training. The integrity of signaling pathways controlling Arc expression was demonstrated by stimulation of the medial perforant path, which induced normal synaptic potentiation and Arc in rats with fornix lesions. Together, the results demonstrate that Arc induction can be decoupled from behavior and is more likely to indicate the engagement of synaptic plasticity mechanisms than synaptic or neuronal activity per se. The results further imply that fornix lesions may impair memory in part by decoupling neuronal activity from signaling pathways required for long-lasting hippocampal synaptic plasticity.
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Matsui H, Nishinaka K, Oda M, Niikawa H, Komatsu K, Kubori T, Udaka F. Disruptions of the fornix fiber in Parkinsonian patients with excessive daytime sleepiness. Parkinsonism Relat Disord 2006; 12:319-22. [PMID: 16621664 DOI: 10.1016/j.parkreldis.2006.01.007] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/05/2006] [Revised: 01/12/2006] [Accepted: 01/23/2006] [Indexed: 10/24/2022]
Abstract
BACKGROUND Although excessive daytime sleepiness (EDS) in Parkinson's disease (PD) has received a great deal of attention, the underlying pathological mechanism of its development and the relative contributions of brain function to this process are poorly understood. OBJECTIVE To compare the fractional anisotropy (FA) values of PD patients with EDS and those without EDS, and to investigate the mechanism of EDS in this disease. METHODS Eleven patients with PD with EDS, 26 patients with PD without EDS and 10 controls participated in this study. Patients with an ESS (Epworth Sleepiness Scale) score >or=10 were defined as having EDS. The FA values of 5 regions of interest (ROI) including the fornix were compared between the three groups. RESULTS There were significant reductions in FA values of the fornix fiber in patients with EDS. ESS scores had significant correlation with FA values of the fornix. CONCLUSIONS Our study is the first to find the fornix fiber degeneration in PD patients with EDS. These results indicate that fornix dysfunction may have some correlations with EDS in PD.
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Affiliation(s)
- Hideaki Matsui
- Department of Neurology, Sumitomo Hospital, 5-3-20 Nakanoshima, Osaka 530-0005, Japan.
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Naumann T, Schnell O, Zhi Q, Kirsch M, Schubert KO, Sendtner M, Hofmann HD. Endogenous ciliary neurotrophic factor protects GABAergic, but not cholinergic, septohippocampal neurons following fimbria-fornix transection. Brain Pathol 2006; 13:309-21. [PMID: 12946020 PMCID: PMC8095902 DOI: 10.1111/j.1750-3639.2003.tb00030.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
Application of neurotrophic proteins including ciliary neurotrophic factor (CNTF) and leukemia inhibitory factor (LIF), members of the family of gp130-associated cytokines, can rescue CNS neurons from injury-induced degeneration. However, it is not clear so far if these effects reflect a physiological function of the endogenous cytokines. Using fimbria-fornix transection as a model, we examined whether responses of GABAergic and cholinergic septohippocampal neurons to axotomy are altered in mice lacking CNTF. In addition, we studied the cellular expression of CNTF, LIF and related cytokine receptor components in the septal complex following lesion. Degeneration of septohippocampal GABAergic neurons in the medial septum as indicated by the loss of parvalbumin-immunoreactive neurons was accelerated and permanently enhanced in CNTF(-/-) mice as compared to wild-type animals. Unexpectedly, the number of axotomized cholinergic MS neurons was significantly higher in CNTF-deficient mice during the first 2 weeks postlesion. Both in wild-type and in CNTF(-/-) mutants, expression of mRNA for the CNTF-specific alpha-subunit of the cytokine receptor complex was specifically upregulated in axotomized GABAergic septal neurons, whereas enhanced expression of the LIF-binding beta-subunit was specifically observed in axotomized cholinergic neurons. Following lesion, CNTF expression in wild-type mice was induced in activated astrocytes surrounding the axotomized neurons and at the lesion site. Expression of LIF mRNA was localized in the GABAergic and cholinergic septohippocampal neurons. These results strongly indicate that endogenous CNTF, supplied by reactive glia cells, acts as a neuroprotective factor for axotomized CNS neurons. In the septum, endogenous CNTF specifically supports lesioned GABAergic projection neurons, whereas LIF may play a similar role for the cholinergic counterparts.
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46
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Brasted PJ, Bussey TJ, Murray EA, Wise SP. Conditional motor learning in the nonspatial domain: effects of errorless learning and the contribution of the fornix to one-trial learning. Behav Neurosci 2005; 119:662-76. [PMID: 15998187 DOI: 10.1037/0735-7044.119.3.662] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Conditional motor learning contributes importantly to behavioral flexibility. In previous work, the authors found that fornix transections impaired the ability of macaque monkeys (Macaca mulatta) to learn conditional motor associations between the nonspatial features of visual stimuli and nonspatially differentiated responses. In the present study, they found that significant 1-trial learning of such associations also depended on the fornix. Furthermore, removal of the hippocampus, subiculum, and subjacent parahippocampal cortex, added to fornix transection, had no effect, thus demonstrating that fornix transections eliminated the contribution of the hippocampal system. In addition, the authors examined the effect of errorless learning and found, in control monkeys, that errors made prior to the 1st correct response retarded 1-trial learning.
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Affiliation(s)
- Peter J Brasted
- Laboratory of Systems Neuroscience, National Institute of Mental Health, Bethesda, MD 20892-4401, USA
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White NM, Chai SC, Hamdani S. Learning the morphine conditioned cue preference: Cue configuration determines effects of lesions. Pharmacol Biochem Behav 2005; 81:786-96. [PMID: 16009410 DOI: 10.1016/j.pbb.2005.06.002] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/27/2005] [Revised: 06/01/2005] [Accepted: 06/04/2005] [Indexed: 11/29/2022]
Abstract
The morphine conditioned cue preference was investigated using two different apparatus configurations. In one configuration, with a clear Plexiglas partition separating the drug-paired and unpaired compartments, rats could see the cues in both compartments while in either one. In the other configuration, with an opaque wood partition separating the two compartments, rats could see the cues in only one compartment at a time. The experiment had three phases: a session of pre-exposure to the entire apparatus; four 2-day training trials during each of which rats received pairings of 5 mg/Kg morphine sulphate with one compartment and saline with the other (compartments and order counterbalanced), and a test session in which the undrugged rats moved freely between the compartments while the time spent in each was measured. Four groups of rats were trained using the opaque partition in all three phases. Normal rats and rats with amygdala or nucleus accumbens lesions exhibited preferences for their morphine-paired compartments; rats with fimbria-fornix lesions had no preferences. Four additional groups were trained using the clear partition during pre-exposure, the opaque partition during training and the clear partition during testing. Normal rats and rats with fimbria-fornix lesions exhibited preferences, rats with amygdala or nucleus accumbens lesions had no preferences. This interaction between lesioned structures and the apparatus configuration is accounted for by the idea that different types of learning produced the preference for morphine-paired cues in the two apparatus configurations. Each type was learned in a different memory system and so was impaired by different lesions. These findings contribute to understanding the nature of the learning processes that produce the morphine CCP.
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Affiliation(s)
- Norman M White
- Department of Psychology, McGill University, 1205 Dr Penfield Avenue, Montreal, Canada QC H3A 1B1.
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Urbach H, Siebenhaar G, Koenig R, von Oertzen J, Scorzin J, Kurthen M, Schild HH. Limbic System Abnormalities Associated with Ammon's Horn Sclerosis Do Not Alter Seizure Outcome after Amygdalohippocampectomy. Epilepsia 2005; 46:549-55. [PMID: 15816949 DOI: 10.1111/j.0013-9580.2005.29104.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
PURPOSE To evaluate whether limbic system abnormalities associated with Ammon's horn sclerosis alter seizure outcome after selective amgydalohippocampectomy. METHODS In 45 patients with unilateral mesial temporal lobe epilepsy, histologically proven Ammon's horn sclerosis, and uneventful postoperative course, volumes of the hippocampus, hemisphere, amygdala, entorhinal cortex, mamillary body, and fornix were measured by using a T(1)-weighted 3-D gradient-echo sequence with roughly isotropic (1.17 x 1.17 x 1-mm) voxels. In addition, signal intensity of the hippocampus and of the temporal lobe white matter was visually assessed and graded on a coronal T(2)-weighted fast-spin-echo sequence with 2-mm-thick slices. Volumetric measurements and visual analysis were compared between seizure-free and non-seizure-free patients examined 12 months after surgery. RESULTS Hippocampal, hemispheric, entorhinal cortex, mamillary body, and fornix volumes, but not amygdalar volumes, were significantly smaller on the operated-on than on the non-operated-on side and significantly smaller in patients compared with controls. No volume differences of the hippocampus, hemisphere, amygdala, entorhinal cortex, mamillary body, and fornix existed between seizure-free (Engel class IA) and non-seizure-free patients (Engel class IB-IV). Increased temporal lobe white matter signal was observed in 15 patients but did not alter seizure outcome. CONCLUSIONS Limbic system abnormalities are not a surrogate marker to predict postsurgical seizure outcome in patients with unilateral Ammon's horn sclerosis.
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Affiliation(s)
- Horst Urbach
- Department of Radiology, University of Bonn Medical Center, Bonn, Germany.
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Tomaiuolo F, Carlesimo GA, Di Paola M, Petrides M, Fera F, Bonanni R, Formisano R, Pasqualetti P, Caltagirone C. Gross morphology and morphometric sequelae in the hippocampus, fornix, and corpus callosum of patients with severe non-missile traumatic brain injury without macroscopically detectable lesions: a T1 weighted MRI study. J Neurol Neurosurg Psychiatry 2004; 75:1314-22. [PMID: 15314123 PMCID: PMC1739237 DOI: 10.1136/jnnp.2003.017046] [Citation(s) in RCA: 115] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
OBJECTIVE The gross morphology and morphometry of the hippocampus, fornix, and corpus callosum in patients with severe non-missile traumatic brain injury (nmTBI) without obvious neuroradiological lesions was examined and the volumes of these structures were correlated with performance on memory tests. In addition, the predictability of the length of coma from the selected anatomical volumes was examined. METHOD High spatial resolution T1 weighted MRI scans of the brain (1 mm3) and neuropsychological evaluations with standardised tests were performed at least 3 months after trauma in 19 patients. RESULTS In comparison with control subjects matched in terms of gender and age, volume reduction in the hippocampus, fornix, and corpus callosum of the nmTBI patients was quantitatively significant. The length of coma correlated with the volume reduction in the corpus callosum. Immediate free recall of word lists correlated with the volume of the fornix and the corpus callosum. Delayed recall of word lists and immediate recall of the Rey figure both correlated with the volume of the fornix. Delayed recall of the Rey figure correlated with the volume of the fornix and the right hippocampus. CONCLUSION These findings demonstrate that in severe nmTBI without obvious neuroradiological lesions there is a clear hippocampal, fornix, and callosal volume reduction. The length of coma predicts the callosal volume reduction, which could be considered a marker of the severity of axonal loss. A few memory test scores correlated with the volumes of the selected anatomical structures. This relationship with memory performance may reflect the diffuse nature of the damage, leading to the disruption of neural circuits at multiple levels and the progressive neural degeneration occurring in TBI.
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Affiliation(s)
- F Tomaiuolo
- IRCCS Fondazione 'Santa Lucia', Rome, Italy.
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50
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Abstract
A thick longitudinal fiber bundle found within the dorsal corpus callosum in two unrelated adults (in a micrencephalic female patient and incidentally in another male patient) is considered to be a congenital aberrant cingulum. Agenesis or apparent hypoplasia of the indusium griseum of the limbic-cingular system as an accompanying finding in the present cases may support this hypothesis. The dorsal fornix and Probst bundle are discussed in terms of differential diagnosis, although there was no further support for this possibility. The hyperplastic dorsocallosal gray substance is excluded.
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Affiliation(s)
- Akira Hori
- Institute of Neuropathology, Medizinische Hochschule Hannover, Germany.
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