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Clark BJ, LaChance PA, Winter SS, Mehlman ML, Butler W, LaCour A, Taube JS. Comparison of head direction cell firing characteristics across thalamo-parahippocampal circuitry. Hippocampus 2024; 34:168-196. [PMID: 38178693 PMCID: PMC10950528 DOI: 10.1002/hipo.23596] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2023] [Revised: 11/24/2023] [Accepted: 12/03/2023] [Indexed: 01/06/2024]
Abstract
Head direction (HD) cells, which fire persistently when an animal's head is pointed in a particular direction, are widely thought to underlie an animal's sense of spatial orientation and have been identified in several limbic brain regions. Robust HD cell firing is observed throughout the thalamo-parahippocampal system, although recent studies report that parahippocampal HD cells exhibit distinct firing properties, including conjunctive aspects with other spatial parameters, which suggest they play a specialized role in spatial processing. Few studies, however, have quantified these apparent differences. Here, we performed a comparative assessment of HD cell firing characteristics across the anterior dorsal thalamus (ADN), postsubiculum (PoS), parasubiculum (PaS), medial entorhinal (MEC), and postrhinal (POR) cortices. We report that HD cells with a high degree of directional specificity were observed in all five brain regions, but ADN HD cells display greater sharpness and stability in their preferred directions, and greater anticipation of future headings compared to parahippocampal regions. Additional analysis indicated that POR HD cells were more coarsely modulated by other spatial parameters compared to PoS, PaS, and MEC. Finally, our analyses indicated that the sharpness of HD tuning decreased as a function of laminar position and conjunctive coding within the PoS, PaS, and MEC, with cells in the superficial layers along with conjunctive firing properties showing less robust directional tuning. The results are discussed in relation to theories of functional organization of HD cell tuning in thalamo-parahippocampal circuitry.
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Affiliation(s)
- Benjamin J Clark
- Department of Psychology, University of New Mexico, Albuquerque, New Mexico, USA
| | - Patrick A LaChance
- Department of Psychological and Brain Sciences, Center for Cognitive Neuroscience, Dartmouth College, Hanover, New Hampshire, USA
| | - Shawn S Winter
- Department of Psychological and Brain Sciences, Center for Cognitive Neuroscience, Dartmouth College, Hanover, New Hampshire, USA
| | - Max L Mehlman
- Department of Psychological and Brain Sciences, Center for Cognitive Neuroscience, Dartmouth College, Hanover, New Hampshire, USA
| | - Will Butler
- Department of Psychological and Brain Sciences, Center for Cognitive Neuroscience, Dartmouth College, Hanover, New Hampshire, USA
| | - Ariyana LaCour
- Department of Psychology, University of New Mexico, Albuquerque, New Mexico, USA
| | - Jeffrey S Taube
- Department of Psychological and Brain Sciences, Center for Cognitive Neuroscience, Dartmouth College, Hanover, New Hampshire, USA
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Gonzalez A, Giocomo LM. Parahippocampal neurons encode task-relevant information for goal-directed navigation. eLife 2024; 12:RP85646. [PMID: 38363198 PMCID: PMC10942598 DOI: 10.7554/elife.85646] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2024] Open
Abstract
A behavioral strategy crucial to survival is directed navigation to a goal, such as a food or home location. One potential neural substrate for supporting goal-directed navigation is the parahippocampus, which contains neurons that represent an animal's position, orientation, and movement through the world, and that change their firing activity to encode behaviorally relevant variables such as reward. However, little prior work on the parahippocampus has considered how neurons encode variables during goal-directed navigation in environments that dynamically change. Here, we recorded single units from rat parahippocampal cortex while subjects performed a goal-directed task. The maze dynamically changed goal-locations via a visual cue on a trial-to-trial basis, requiring subjects to use cue-location associations to receive reward. We observed a mismatch-like signal, with elevated neural activity on incorrect trials, leading to rate-remapping. The strength of this remapping correlated with task performance. Recordings during open-field foraging allowed us to functionally define navigational coding for a subset of the neurons recorded in the maze. This approach revealed that head-direction coding units remapped more than other functional-defined units. Taken together, this work thus raises the possibility that during goal-directed navigation, parahippocampal neurons encode error information reflective of an animal's behavioral performance.
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Affiliation(s)
- Alexander Gonzalez
- Department of Neurobiology, Stanford University School of MedicineStanfordUnited States
| | - Lisa M Giocomo
- Department of Neurobiology, Stanford University School of MedicineStanfordUnited States
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3
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Traub RD, Whittington MA, Cunningham MO. Simulation of oscillatory dynamics induced by an approximation of grid cell output. Rev Neurosci 2023; 34:517-532. [PMID: 36326795 PMCID: PMC10329426 DOI: 10.1515/revneuro-2022-0107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Accepted: 10/06/2022] [Indexed: 07/20/2023]
Abstract
Grid cells, in entorhinal cortex (EC) and related structures, signal animal location relative to hexagonal tilings of 2D space. A number of modeling papers have addressed the question of how grid firing behaviors emerge using (for example) ideas borrowed from dynamical systems (attractors) or from coupled oscillator theory. Here we use a different approach: instead of asking how grid behavior emerges, we take as a given the experimentally observed intracellular potentials of superficial medial EC neurons during grid firing. Employing a detailed neural circuit model modified from a lateral EC model, we then ask how the circuit responds when group of medial EC principal neurons exhibit such potentials, simultaneously with a simulated theta frequency input from the septal nuclei. The model predicts the emergence of robust theta-modulated gamma/beta oscillations, suggestive of oscillations observed in an in vitro medial EC experimental model (Cunningham, M.O., Pervouchine, D.D., Racca, C., Kopell, N.J., Davies, C.H., Jones, R.S.G., Traub, R.D., and Whittington, M.A. (2006). Neuronal metabolism governs cortical network response state. Proc. Natl. Acad. Sci. U S A 103: 5597-5601). Such oscillations result because feedback interneurons tightly synchronize with each other - despite the varying phases of the grid cells - and generate a robust inhibition-based rhythm. The lack of spatial specificity of the model interneurons is consistent with the lack of spatial periodicity in parvalbumin interneurons observed by Buetfering, C., Allen, K., and Monyer, H. (2014). Parvalbumin interneurons provide grid cell-driven recurrent inhibition in the medial entorhinal cortex. Nat. Neurosci. 17: 710-718. If in vivo EC gamma rhythms arise during exploration as our model predicts, there could be implications for interpreting disrupted spatial behavior and gamma oscillations in animal models of Alzheimer's disease and schizophrenia. Noting that experimental intracellular grid cell potentials closely resemble cortical Up states and Down states, during which fast oscillations also occur during Up states, we propose that the co-occurrence of slow principal cell depolarizations and fast network oscillations is a general property of the telencephalon, in both waking and sleep states.
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Affiliation(s)
- Roger D. Traub
- AI Foundations, IBM T.J. Watson Research Center, Yorktown Heights, NY10598, USA
- Department of Neuroscience, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA19104, USA
| | | | - Mark O. Cunningham
- Discipline of Physiology, School of Medicine, Trinity College Dublin, University of Dublin, 152-160 Pearse St., Dublin 2, Ireland
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4
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Cao P, Chen C, Si Q, Li Y, Ren F, Han C, Zhao J, Wang X, Xu G, Sui Y. Volumes of hippocampal subfields suggest a continuum between schizophrenia, major depressive disorder and bipolar disorder. Front Psychiatry 2023; 14:1191170. [PMID: 37547217 PMCID: PMC10400724 DOI: 10.3389/fpsyt.2023.1191170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Accepted: 07/03/2023] [Indexed: 08/08/2023] Open
Abstract
Objective There is considerable debate as to whether the continuum of major psychiatric disorders exists and to what extent the boundaries extend. Converging evidence suggests that alterations in hippocampal volume are a common sign in psychiatric disorders; however, there is still no consensus on the nature and extent of hippocampal atrophy in schizophrenia (SZ), major depressive disorder (MDD) and bipolar disorder (BD). The aim of this study was to verify the continuum of SZ - BD - MDD at the level of hippocampal subfield volume and to compare the volume differences in hippocampal subfields in the continuum. Methods A total of 412 participants (204 SZ, 98 MDD, and 110 BD) underwent 3 T MRI scans, structured clinical interviews, and clinical scales. We segmented the hippocampal subfields with FreeSurfer 7.1.1 and compared subfields volumes across the three diagnostic groups by controlling for age, gender, education, and intracranial volumes. Results The results showed a gradual increase in hippocampal subfield volumes from SZ to MDD to BD. Significant volume differences in the total hippocampus and 13 of 26 hippocampal subfields, including CA1, CA3, CA4, GC-ML-DG, molecular layer and the whole hippocampus, bilaterally, and parasubiculum in the right hemisphere, were observed among diagnostic groups. Medication treatment had the most effect on subfields of MDD compared to SZ and BD. Subfield volumes were negatively correlated with illness duration of MDD. Positive correlations were found between subfield volumes and drug dose in SZ and MDD. There was no significant difference in laterality between diagnostic groups. Conclusion The pattern of hippocampal volume reduction in SZ, MDD and BD suggests that there may be a continuum of the three disorders at the hippocampal level. The hippocampus represents a phenotype that is distinct from traditional diagnostic strategies. Combined with illness duration and drug intervention, it may better reflect shared pathophysiology and mechanisms across psychiatric disorders.
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Affiliation(s)
- Peiyu Cao
- Department of Psychiatry, The Affiliated Brain Hospital of Nanjing Medical University, Nanjing Brain Hospital, Nanjing, China
| | - Congxin Chen
- Women’s Hospital of Nanjing Medical University, Nanjing Maternity and Child Health Care Hospital, Nanjing, China
| | - Qi Si
- Department of Psychiatry, The Affiliated Brain Hospital of Nanjing Medical University, Nanjing Brain Hospital, Nanjing, China
- Huai’an No. 3 People’s Hospital, Huai’an, China
| | - Yuting Li
- Department of Psychiatry, The Affiliated Brain Hospital of Nanjing Medical University, Nanjing Brain Hospital, Nanjing, China
| | - Fangfang Ren
- Department of Psychiatry, The Affiliated Brain Hospital of Nanjing Medical University, Nanjing Brain Hospital, Nanjing, China
| | - Chongyang Han
- Department of Psychiatry, The Affiliated Brain Hospital of Nanjing Medical University, Nanjing Brain Hospital, Nanjing, China
| | - Jingjing Zhao
- Department of Psychiatry, The Affiliated Brain Hospital of Nanjing Medical University, Nanjing Brain Hospital, Nanjing, China
| | - Xiying Wang
- Department of Psychiatry, The Affiliated Brain Hospital of Nanjing Medical University, Nanjing Brain Hospital, Nanjing, China
| | - Guoxin Xu
- Department of Psychiatry, The Affiliated Brain Hospital of Nanjing Medical University, Nanjing Brain Hospital, Nanjing, China
| | - Yuxiu Sui
- Department of Psychiatry, The Affiliated Brain Hospital of Nanjing Medical University, Nanjing Brain Hospital, Nanjing, China
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Sun Y, Hu N, Wang M, Lu L, Luo C, Tang B, Yao C, Sweeney JA, Gong Q, Qiu C, Lui S. Hippocampal subfield alterations in schizophrenia and major depressive disorder: a systematic review and network meta-analysis of anatomic MRI studies. J Psychiatry Neurosci 2023; 48:E34-E49. [PMID: 36750240 PMCID: PMC9911126 DOI: 10.1503/jpn.220086] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Revised: 07/28/2022] [Accepted: 10/30/2022] [Indexed: 02/09/2023] Open
Abstract
BACKGROUND Hippocampal disturbances are important in the pathophysiology of both schizophrenia and major depressive disorder (MDD). Imaging studies have shown selective volume deficits across hippocampal subfields in both disorders. We aimed to investigate whether these volumetric alterations in hippocampal subfields are shared or divergent across disorders. METHODS We searched PubMed and Embase from database inception to May 8, 2021. We identified MRI studies in patients with schizophrenia, MDD or both, in which hippocampal subfield volumes were measured. We excluded nonoriginal, animal or postmortem studies, and studies that used other imaging modalities or overlapping data. We conducted a network meta-analysis to estimate and contrast alterations in subfield volumes in the 2 disorders. RESULTS We identified 45 studies that met the initial criteria for systematic review, of which 15 were eligible for network metaanalysis. Compared to healthy controls, patients with schizophrenia had reduced volumes in the bilateral cornu ammonis (CA) 1, granule cell layer of the dentate gyrus, subiculum, parasubiculum, molecular layer, hippocampal tail and hippocampus-amygdala transition area (HATA); in the left CA4 and presubiculum; and in the right fimbria. Patients with MDD had decreased volumes in the left CA3 and CA4 and increased volumes in the right HATA compared to healthy controls. The bilateral parasubiculum and right HATA were smaller in patients with schizophrenia than in patients with MDD. LIMITATIONS We did not investigate medication effects because of limited information. Study heterogeneity was noteworthy in direct comparisons between patients with MDD and healthy controls. CONCLUSION The volumes of multiple hippocampal subfields are selectively altered in patients with schizophrenia and MDD, with overlap and differentiation in subfield alterations across disorders. Rigorous head-to-head studies are needed to validate our findings.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | - Changjian Qiu
- From the Huaxi MR Research Center, Department of Radiology and National Clinical Research Center for Geriatrics, West China Hospital of Sichuan University, Chengdu, Sichuan, China (Sun, Lu, Tang, Yao, Sweeney, Gong, Lui); the Department of Radiology, West China Hospital of Sichuan University, Chengdu, Sichuan, China (Hu, Luo); the Chinese Evidence-Based Medicine Center and Cochrane China Center, West China Hospital of Sichuan University, Chengdu, Sichuan, China (Wang); the Department of Psychiatry and Behavioral Neuroscience, University of Cincinnati, Cincinnati, Ohio, United States (Sweeney); the Mental Health Center, West China Hospital of Sichuan University, Chengdu, Sichuan, China (Qiu); the Research Unit of Psychoradiology, Chinese Academy of Medical Sciences, Chengdu, Sichuan, China (Lui); the Functional and Molecular Imaging Key Laboratory of Sichuan Province, West China Hospital of Sichuan University, Chengdu, Sichuan, China (Lui)
| | - Su Lui
- From the Huaxi MR Research Center, Department of Radiology and National Clinical Research Center for Geriatrics, West China Hospital of Sichuan University, Chengdu, Sichuan, China (Sun, Lu, Tang, Yao, Sweeney, Gong, Lui); the Department of Radiology, West China Hospital of Sichuan University, Chengdu, Sichuan, China (Hu, Luo); the Chinese Evidence-Based Medicine Center and Cochrane China Center, West China Hospital of Sichuan University, Chengdu, Sichuan, China (Wang); the Department of Psychiatry and Behavioral Neuroscience, University of Cincinnati, Cincinnati, Ohio, United States (Sweeney); the Mental Health Center, West China Hospital of Sichuan University, Chengdu, Sichuan, China (Qiu); the Research Unit of Psychoradiology, Chinese Academy of Medical Sciences, Chengdu, Sichuan, China (Lui); the Functional and Molecular Imaging Key Laboratory of Sichuan Province, West China Hospital of Sichuan University, Chengdu, Sichuan, China (Lui)
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Wan M, Xia R, Lin H, Ye Y, Qiu P, Zheng G. Baduanjin exercise modulates the hippocampal subregion structure in community-dwelling older adults with cognitive frailty. Front Aging Neurosci 2022; 14:956273. [PMID: 36600804 PMCID: PMC9806122 DOI: 10.3389/fnagi.2022.956273] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Accepted: 11/29/2022] [Indexed: 12/23/2022] Open
Abstract
Background Regular Baduanjin exercise intervention was proven to be beneficial in improving the cognitive ability and physical performance of older adults with different health conditions but was unclear to influence the structural plasticity of the hippocampus. This study aimed to explore the modulation of hippocampal subregions as a mechanism by which Baduanjin exercise improves cognitive frailty in older adults. Methods A total of 102 community-dwelling older adults with cognitive frailty were recruited and randomly allocated to the Baduanjin exercise training group and usual physical activity control group. The participants in the Baduanjin exercise training group participated in a 24-week Baduanjin exercise intervention program with an exercise frequency of 60 min per day, 3 days per week. Cognitive ability and physical frailty were assessed, and MRI scans were performed on all participants at baseline and after 24 weeks of intervention. The structural MRI data were processed with MRIConvert (version 2.0 Rev. 235) and FreeSurfer (version 6.0.0) software. Data analyses were performed using the independent sample t tests/Mann-Whitney U tests with the Bonferroni correction, mixed linear model, correlation, or mediation analysis by the SPSS 24.0 software (IBM Corp, Armonk, NY, United States). Results After 24 weeks of intervention, a statistically significant increase was found for the Montreal Cognitive Assessment (MoCA) scores (p = 0.002) with a large effect size (Cohen's d = 0.94) and the significant interaction effect (P goup × time < 0.05), Memory Quotient (MQ) scores (p = 0.019) with a medium effect size (Cohen's d = 0.688) and the significant interaction effect (P goup × time < 0.05), and other parameters of WMS-RC test including pictures (p = 0.042), recognition (p = 0.017), and association (p = 0.045) test with a medium effect size (Cohens' d = 0.592, 0.703, and 0.581) for the Baduanjin training group, while significant decrease for the Edmonton Frailty Scale (EFS) score (p = 0.022), with a medium effect size (Cohen's d = -0.659) and the significant interaction effect (P goup × time < 0.05) for the Baduanjin training group. The differences in the left parasubiculum, Hippocampal Amygdala Transition Area (HATA), right Cornu Ammonis Subfield 1 (CA1) and presubiculum volumes from baseline to 24 weeks after intervention in the Baduanjin training group were significantly greater than those in the control group (p < 0.05/12). Further analysis showed that the changes in right CA1 volume were positively correlated with the changes in MoCA and MQ scores (r = 0.510, p = 0.015; r = 0.484, p = 0.022;), the changes in right presubiculum and left parasubiculum volumes were positively correlated with the changes in MQ (r = 0.435, p = 0.043) and picture test scores (r = 0.509, p = 0.016), respectively, and the changes in left parasubiculum and HATA volumes were negatively correlated with the changes in EFS scores (r = -0.534, p = 0.011; r = -0.575, p = 0.005) in the Baduanjin training group, even after adjusting for age, sex, years of education and marital status; furthermore, the volume changes in left parasubiculum and left HATA significantly mediated the Baduanjin exercise training-induced decrease in the EFS scores (β = 0.376, 95% CI 0.024 ~ 0.947; β = 0.484, 95% CI 0.091 ~ 0.995); the changes of left parasubiculum and right CA1 significantly mediated the Baduanjin exercise training-induced increase in the picture and MO scores (β = -0.83, 95% CI-1.95 ~ -0.002; β = -2.44, 95% CI-5.99 ~ -0.32). Conclusion A 24-week Baduanjin exercise intervention effectively improved cognitive ability and reduced physical frailty in community-dwelling older adults with cognitive frailty, and the mechanism might be associated with modulating the structural plasticity of the hippocampal subregion.
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Affiliation(s)
- Mingyue Wan
- School of Rehabilitation Sciences, Southern Medical University, Guangzhou, China,College of Nursing and Health Management, Shanghai University of Medicine and Health Sciences, Shanghai, China,College of Rehabilitation Medicine, Fujian University of Traditional Chinese Medicine, Fuzhou, China
| | - Rui Xia
- College of Rehabilitation Medicine, Fujian University of Traditional Chinese Medicine, Fuzhou, China,Department of Rehabilitation, Shenzhen Bao ‘an District People’s Hospital, Shenzhen, China
| | - Huiying Lin
- College of Rehabilitation Medicine, Fujian University of Traditional Chinese Medicine, Fuzhou, China
| | - Yu Ye
- College of Rehabilitation Medicine, Fujian University of Traditional Chinese Medicine, Fuzhou, China
| | - Pingting Qiu
- College of Rehabilitation Medicine, Fujian University of Traditional Chinese Medicine, Fuzhou, China
| | - Guohua Zheng
- College of Nursing and Health Management, Shanghai University of Medicine and Health Sciences, Shanghai, China,*Correspondence: Guohua Zheng,
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7
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Zhao R, Grunke SD, Wood CA, Perez GA, Comstock M, Li MH, Singh AK, Park KW, Jankowsky JL. Activity disruption causes degeneration of entorhinal neurons in a mouse model of Alzheimer's circuit dysfunction. eLife 2022; 11:e83813. [PMID: 36468693 PMCID: PMC9873254 DOI: 10.7554/elife.83813] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Accepted: 12/03/2022] [Indexed: 12/12/2022] Open
Abstract
Neurodegenerative diseases are characterized by selective vulnerability of distinct cell populations; however, the cause for this specificity remains elusive. Here, we show that entorhinal cortex layer 2 (EC2) neurons are unusually vulnerable to prolonged neuronal inactivity compared with neighboring regions of the temporal lobe, and that reelin + stellate cells connecting EC with the hippocampus are preferentially susceptible within the EC2 population. We demonstrate that neuronal death after silencing can be elicited through multiple independent means of activity inhibition, and that preventing synaptic release, either alone or in combination with electrical shunting, is sufficient to elicit silencing-induced degeneration. Finally, we discovered that degeneration following synaptic silencing is governed by competition between active and inactive cells, which is a circuit refinement process traditionally thought to end early in postnatal life. Our data suggests that the developmental window for wholesale circuit plasticity may extend into adulthood for specific brain regions. We speculate that this sustained potential for remodeling by entorhinal neurons may support lifelong memory but renders them vulnerable to prolonged activity changes in disease.
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Affiliation(s)
- Rong Zhao
- Department of Neuroscience, Huffington Center on Aging, Baylor College of MedicineHoustonUnited States
| | - Stacy D Grunke
- Department of Neuroscience, Huffington Center on Aging, Baylor College of MedicineHoustonUnited States
| | - Caleb A Wood
- Department of Neuroscience, Huffington Center on Aging, Baylor College of MedicineHoustonUnited States
| | - Gabriella A Perez
- Department of Neuroscience, Huffington Center on Aging, Baylor College of MedicineHoustonUnited States
| | - Melissa Comstock
- Department of Neuroscience, Huffington Center on Aging, Baylor College of MedicineHoustonUnited States
| | - Ming-Hua Li
- Department of Neuroscience, Huffington Center on Aging, Baylor College of MedicineHoustonUnited States
| | - Anand K Singh
- Department of Neuroscience, Huffington Center on Aging, Baylor College of MedicineHoustonUnited States
| | - Kyung-Won Park
- Department of Neuroscience, Huffington Center on Aging, Baylor College of MedicineHoustonUnited States
| | - Joanna L Jankowsky
- Department of Neuroscience, Huffington Center on Aging, Baylor College of MedicineHoustonUnited States
- Departments of Neurology, Neurosurgery, and Molecular and Cellular Biology, Huffington Center on Aging, Baylor College of MedicineHoustonUnited States
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8
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Exercise Modulates Brain Glucose Utilization Response to Acute Cocaine. J Pers Med 2022; 12:jpm12121976. [PMID: 36556197 PMCID: PMC9788493 DOI: 10.3390/jpm12121976] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 11/22/2022] [Accepted: 11/25/2022] [Indexed: 12/02/2022] Open
Abstract
Exercise, a proven method of boosting health and wellness, is thought to act as a protective factor against many neurological and psychological diseases. Recent studies on exercise and drug exposure have pinpointed some of the neurological mechanisms that may characterize this protective factor. Using positron emission tomography (PET) imaging techniques and the glucose analog [18F]-Fluorodeoxyglucose (18F-FDG), our team sought to identify how chronic aerobic exercise modulates brain glucose metabolism (BGluM) after drug-naïve rats were exposed to an acute dose of cocaine. Using sedentary rats as a control group, we observed significant differences in regional BGluM. Chronic treadmill exercise treatment coupled with acute cocaine exposure induced responses in BGluM activity in the following brain regions: postsubiculum (Post), parasubiculum (PaS), granular and dysgranular insular cortex (GI and DI, respectively), substantia nigra reticular (SNR) and compact part dorsal tier (SNCD), temporal association cortex (TeA), entopenduncular nucleus (EP), and crus 1 of the ansiform lobule (crus 1). Inhibition, characterized by decreased responses due to our exercise, was found in the ventral endopiriform nucleus (VEn). These areas are associated with memory and various motor functions. They also include and share connections with densely dopaminergic areas of the mesolimbic system. In conclusion, these findings suggest that treadmill exercise in rats mediates brain glucose response to an acute dose of cocaine differently as compared to sedentary rats. The modulated brain glucose utilization occurs in brain regions responsible for memory and association, spatial navigation, and motor control as well as corticomesolimbic regions related to reward, emotion, and movement.
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9
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Chen SQ, Chen CH, Xiang XJ, Zhang SY, Ding SL. Chemoarchitecture of area prostriata in adult and developing mice: Comparison with presubiculum and parasubiculum. J Comp Neurol 2022; 530:2486-2517. [PMID: 35593198 DOI: 10.1002/cne.25346] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Revised: 04/28/2022] [Accepted: 05/02/2022] [Indexed: 11/11/2022]
Abstract
Retrosplenial area 29e, which was a cortical region described mostly in earlier rodent literature, is often included in the dorsal presubiculum (PrSd) or postsubiculum (PoS) in modern literature and commonly used brain atlases. Recent anatomical and molecular studies have revealed that retrosplenial area 29e belongs to the superficial layers of area prostriata, which in primates is found to be important in fast analysis of quickly moving objects in far peripheral visual field. As in primates, the prostriata in rodents adjoins area 29 (granular retrosplenial area), area 30 (agranular retrosplenial area), medial visual cortex, PrSd/PoS, parasubiculum (PaS), and postrhinal cortex (PoR). The present study aims to reveal the chemoarchitecture of the prostriata versus PrSd/PoS or PaS by means of a systematic survey of gene expression patterns in adult and developing mouse brains. First, we find many genes that display differential expression across the prostriata, PrSd/PoS, and PaS and that show obvious laminar expression patterns. Second, we reveal subsets of genes that selectively express in the dorsal or ventral parts of the prostriata, suggesting the existence of at least two subdivisions. Third, we detect some genes that shows differential expression in the prostriata of postnatal mouse brains from adjoining regions, thus enabling identification of the developing area prostriata. Fourth, gene expression difference of the prostriata from the medial primary visual cortex and PoR is also observed. Finally, molecular and connectional features of the prostriata in rodents and nonhuman primates are discussed and compared.
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Affiliation(s)
- Sheng-Qiang Chen
- Key Laboratory of Neuroscience, School of Basic Medical Sciences, Guangzhou Medical University, Guangzhou, China.,Institute of Neuroscience, The Second Affiliated Hospital, Guangzhou Medical University, Guangzhou, China
| | - Chang-Hui Chen
- Key Laboratory of Neuroscience, School of Basic Medical Sciences, Guangzhou Medical University, Guangzhou, China.,Institute of Neuroscience, The Second Affiliated Hospital, Guangzhou Medical University, Guangzhou, China
| | - Xiao-Jun Xiang
- Key Laboratory of Neuroscience, School of Basic Medical Sciences, Guangzhou Medical University, Guangzhou, China.,Institute of Neuroscience, The Second Affiliated Hospital, Guangzhou Medical University, Guangzhou, China
| | - Shun-Yu Zhang
- Key Laboratory of Neuroscience, School of Basic Medical Sciences, Guangzhou Medical University, Guangzhou, China.,Institute of Neuroscience, The Second Affiliated Hospital, Guangzhou Medical University, Guangzhou, China
| | - Song-Lin Ding
- Key Laboratory of Neuroscience, School of Basic Medical Sciences, Guangzhou Medical University, Guangzhou, China.,Institute of Neuroscience, The Second Affiliated Hospital, Guangzhou Medical University, Guangzhou, China.,Allen Institute for Brain Science, Seattle, Washington, USA
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10
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Abstract
The investigation of the topographic organization of spatially coding cell types in the medial entorhinal cortex (MEC) has so far been held back by the lack of appropriate tools that enable the precise recording of both the anatomical location and activity of large populations of cells while animals forage in open environments. In this study, we use the newest generation of head-mounted, miniaturized two-photon microscopes to image grid, head-direction, border, as well as object-vector cells in MEC and neighboring parasubiculum within the same animals. The majority of cell types were intermingled, but grid and object-vector cells exhibited little overlap. The results have implications for network models of spatial coding. The medial entorhinal cortex (MEC) creates a map of local space, based on the firing patterns of grid, head-direction (HD), border, and object-vector (OV) cells. How these cell types are organized anatomically is debated. In-depth analysis of this question requires collection of precise anatomical and activity data across large populations of neurons during unrestrained behavior, which neither electrophysiological nor previous imaging methods fully afford. Here, we examined the topographic arrangement of spatially modulated neurons in the superficial layers of MEC and adjacent parasubiculum using miniaturized, portable two-photon microscopes, which allow mice to roam freely in open fields. Grid cells exhibited low levels of co-occurrence with OV cells and clustered anatomically, while border, HD, and OV cells tended to intermingle. These data suggest that grid cell networks might be largely distinct from those of border, HD, and OV cells and that grid cells exhibit strong coupling among themselves but weaker links to other cell types.
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11
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Nyberg N, Duvelle É, Barry C, Spiers HJ. Spatial goal coding in the hippocampal formation. Neuron 2022; 110:394-422. [PMID: 35032426 DOI: 10.1016/j.neuron.2021.12.012] [Citation(s) in RCA: 42] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Revised: 10/18/2021] [Accepted: 12/08/2021] [Indexed: 12/22/2022]
Abstract
The mammalian hippocampal formation contains several distinct populations of neurons involved in representing self-position and orientation. These neurons, which include place, grid, head direction, and boundary-vector cells, are thought to collectively instantiate cognitive maps supporting flexible navigation. However, to flexibly navigate, it is necessary to also maintain internal representations of goal locations, such that goal-directed routes can be planned and executed. Although it has remained unclear how the mammalian brain represents goal locations, multiple neural candidates have recently been uncovered during different phases of navigation. For example, during planning, sequential activation of spatial cells may enable simulation of future routes toward the goal. During travel, modulation of spatial cells by the prospective route, or by distance and direction to the goal, may allow maintenance of route and goal-location information, supporting navigation on an ongoing basis. As the goal is approached, an increased activation of spatial cells may enable the goal location to become distinctly represented within cognitive maps, aiding goal localization. Lastly, after arrival at the goal, sequential activation of spatial cells may represent the just-taken route, enabling route learning and evaluation. Here, we review and synthesize these and other evidence for goal coding in mammalian brains, relate the experimental findings to predictions from computational models, and discuss outstanding questions and future challenges.
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Affiliation(s)
- Nils Nyberg
- Institute of Behavioural Neuroscience, Department of Experimental Psychology, University College London, London, UK.
| | - Éléonore Duvelle
- Department of Psychological and Brain Sciences, Dartmouth College, Hanover, NH, USA
| | - Caswell Barry
- Department of Cell and Developmental Biology, University College London, London, UK
| | - Hugo J Spiers
- Institute of Behavioural Neuroscience, Department of Experimental Psychology, University College London, London, UK.
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12
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Tukker JJ, Beed P, Brecht M, Kempter R, Moser EI, Schmitz D. Microcircuits for spatial coding in the medial entorhinal cortex. Physiol Rev 2021; 102:653-688. [PMID: 34254836 PMCID: PMC8759973 DOI: 10.1152/physrev.00042.2020] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
The hippocampal formation is critically involved in learning and memory and contains a large proportion of neurons encoding aspects of the organism’s spatial surroundings. In the medial entorhinal cortex (MEC), this includes grid cells with their distinctive hexagonal firing fields as well as a host of other functionally defined cell types including head direction cells, speed cells, border cells, and object-vector cells. Such spatial coding emerges from the processing of external inputs by local microcircuits. However, it remains unclear exactly how local microcircuits and their dynamics within the MEC contribute to spatial discharge patterns. In this review we focus on recent investigations of intrinsic MEC connectivity, which have started to describe and quantify both excitatory and inhibitory wiring in the superficial layers of the MEC. Although the picture is far from complete, it appears that these layers contain robust recurrent connectivity that could sustain the attractor dynamics posited to underlie grid pattern formation. These findings pave the way to a deeper understanding of the mechanisms underlying spatial navigation and memory.
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Affiliation(s)
- John J Tukker
- Network Dysfunction, German Center for Neurodegenerative Diseases, Berlin, Germany
| | - Prateep Beed
- NeuroScientific Research Center, Charite Berlin, Germany
| | - Michael Brecht
- Systems Neuroscience, Humboldt University of Berlin, Berlin, Germany
| | - Richard Kempter
- Department of Biology, Institute for Theoretical Biology, Humbolt-Universität zu Berlin, Berlin, Germany
| | - Edvard I Moser
- Kavli Institute for Systems Neuroscience and Centre for the Biology of Memory, Norwegian University of Science and Technology
| | - Dietmar Schmitz
- Neuroscience Research Center, Charité Universitätsmedizin Berlin, Berlin, Germany
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13
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Liu J, Kashima T, Morikawa S, Noguchi A, Ikegaya Y, Matsumoto N. Molecular Characterization of Superficial Layers of the Presubiculum During Development. Front Neuroanat 2021; 15:662724. [PMID: 34234650 PMCID: PMC8256428 DOI: 10.3389/fnana.2021.662724] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Accepted: 04/26/2021] [Indexed: 11/13/2022] Open
Abstract
The presubiculum, a subarea of the parahippocampal region, plays a critical role in spatial navigation and spatial representation. An outstanding aspect of presubicular spatial codes is head-direction selectivity of the firing of excitatory neurons, called head-direction cells. Head-direction selectivity emerges before eye-opening in rodents and is maintained in adulthood through neurophysiological interactions between excitatory and inhibitory neurons. Although the presubiculum has been physiologically profiled in terms of spatial representation during development, the histological characteristics of the developing presubiculum are poorly understood. We found that the expression of vesicular glutamate transporter 2 (VGluT2) could be used to delimit the superficial layers of the presubiculum, which was identified using an anterograde tracer injected into the anterior thalamic nucleus (ATN). Thus, we immunostained slices from mice ranging in age from neonates to adults using an antibody against VGluT2 to evaluate the VGluT2-positive area, which was identified as the superficial layers of the presubiculum, during development. We also immunostained the slices using antibodies against parvalbumin (PV) and somatostatin (SOM) and found that in the presubicular superficial layers, PV-positive neurons progressively increased in number during development, whereas SOM-positive neurons exhibited no increasing trend. In addition, we observed repeating patch structures in presubicular layer III from postnatal days 12. The abundant expression of VGluT2 suggests that the presubicular superficial layers are regulated primarily by VGluT2-mediated excitatory neurotransmission. Moreover, developmental changes in the densities of PV- and SOM-positive interneurons and the emergence of the VGluT2-positive patch structures during adolescence may be associated with the functional development of spatial codes in the superficial layers of the presubiculum.
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Affiliation(s)
- Jiayan Liu
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan
| | - Tetsuhiko Kashima
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan
| | - Shota Morikawa
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan
| | - Asako Noguchi
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan
| | - Yuji Ikegaya
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan.,Institute for AI and Beyond, The University of Tokyo, Tokyo, Japan.,Center for Information and Neural Networks (CiNet), National Institute of Information and Communications Technology, Suita City, Japan
| | - Nobuyoshi Matsumoto
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo, Japan
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14
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Ding SL, Yao Z, Hirokawa KE, Nguyen TN, Graybuck LT, Fong O, Bohn P, Ngo K, Smith KA, Koch C, Phillips JW, Lein ES, Harris JA, Tasic B, Zeng H. Distinct Transcriptomic Cell Types and Neural Circuits of the Subiculum and Prosubiculum along the Dorsal-Ventral Axis. Cell Rep 2021; 31:107648. [PMID: 32433957 DOI: 10.1016/j.celrep.2020.107648] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Revised: 02/23/2020] [Accepted: 04/22/2020] [Indexed: 01/02/2023] Open
Abstract
Subicular regions play important roles in spatial processing and many cognitive functions, and these are mainly attributed to the subiculum (Sub) rather than the prosubiculum (PS). Using single-cell RNA sequencing, we identify 27 transcriptomic cell types residing in sub-domains of the Sub and PS. Based on in situ expression of reliable transcriptomic markers, the precise boundaries of the Sub and PS are consistently defined along the dorsoventral axis. Using these borders to evaluate Cre-line specificity and tracer injections, we find bona fide Sub projections topographically to structures important for spatial processing and navigation. In contrast, the PS sends its outputs to widespread brain regions crucial for motivation, emotion, reward, stress, anxiety, and fear. The Sub and PS, respectively, dominate dorsal and ventral subicular regions and receive different afferents. These results reveal two molecularly and anatomically distinct circuits centered in the Sub and PS, respectively, providing a consistent explanation for historical data and a clearer foundation for future studies.
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Affiliation(s)
- Song-Lin Ding
- Allen Institute for Brain Science, Seattle, WA 98109, USA.
| | - Zizhen Yao
- Allen Institute for Brain Science, Seattle, WA 98109, USA
| | | | | | | | - Olivia Fong
- Allen Institute for Brain Science, Seattle, WA 98109, USA
| | - Phillip Bohn
- Allen Institute for Brain Science, Seattle, WA 98109, USA
| | - Kiet Ngo
- Allen Institute for Brain Science, Seattle, WA 98109, USA
| | | | - Christof Koch
- Allen Institute for Brain Science, Seattle, WA 98109, USA
| | | | - Ed S Lein
- Allen Institute for Brain Science, Seattle, WA 98109, USA
| | - Julie A Harris
- Allen Institute for Brain Science, Seattle, WA 98109, USA
| | - Bosiljka Tasic
- Allen Institute for Brain Science, Seattle, WA 98109, USA
| | - Hongkui Zeng
- Allen Institute for Brain Science, Seattle, WA 98109, USA
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15
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Lepperød ME, Christensen AC, Lensjø KK, Buccino AP, Yu J, Fyhn M, Hafting T. Optogenetic pacing of medial septum parvalbumin-positive cells disrupts temporal but not spatial firing in grid cells. SCIENCE ADVANCES 2021; 7:7/19/eabd5684. [PMID: 33952512 DOI: 10.1126/sciadv.abd5684] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Accepted: 03/17/2021] [Indexed: 06/12/2023]
Abstract
Grid cells in the medial entorhinal cortex (MEC) exhibit remarkable spatial activity patterns with spikes coordinated by theta oscillations driven by the medial septal area (MSA). Spikes from grid cells progress relative to the theta phase in a phenomenon called phase precession, which is suggested as essential to create the spatial periodicity of grid cells. Here, we show that optogenetic activation of parvalbumin-positive (PV+) cells in the MSA enabled selective pacing of local field potential (LFP) oscillations in MEC. During optogenetic stimulation, the grid cells were locked to the imposed pacing frequency but kept their spatial patterns. Phase precession was abolished, and speed information was no longer reflected in the LFP oscillations but was still carried by rate coding of individual MEC neurons. Together, these results support that theta oscillations are not critical to the spatial pattern of grid cells and do not carry a crucial velocity signal.
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Affiliation(s)
- Mikkel Elle Lepperød
- Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
- Centre for Integrative Neuroplasticity, University of Oslo, Oslo, Norway
| | - Ane Charlotte Christensen
- Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway
- Centre for Integrative Neuroplasticity, University of Oslo, Oslo, Norway
| | - Kristian Kinden Lensjø
- Centre for Integrative Neuroplasticity, University of Oslo, Oslo, Norway
- Department of Biosciences, University of Oslo, Oslo, Norway
| | - Alessio Paolo Buccino
- Centre for Integrative Neuroplasticity, University of Oslo, Oslo, Norway
- Department of Informatics, University of Oslo, Oslo, Norway
| | - Jai Yu
- Department of Psychology, Institute for Mind and Biology, Grossman Institute for Neuroscience, and Quantitative Biology and Human Behavior, University of Chicago, 5848 S. University Avenue, Chicago, IL 60637, USA
| | - Marianne Fyhn
- Centre for Integrative Neuroplasticity, University of Oslo, Oslo, Norway
- Department of Biosciences, University of Oslo, Oslo, Norway
| | - Torkel Hafting
- Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway.
- Centre for Integrative Neuroplasticity, University of Oslo, Oslo, Norway
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16
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Modularization of grid cells constrained by the pyramidal patch lattice. iScience 2021; 24:102301. [PMID: 33870125 PMCID: PMC8042349 DOI: 10.1016/j.isci.2021.102301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2020] [Revised: 11/15/2020] [Accepted: 03/10/2021] [Indexed: 11/29/2022] Open
Abstract
Grid cells provide a metric representation of self-location. They are organized into modules, showing discretized scales of grid spacing, but the underlying mechanism remains elusive. In this modeling study, we propose that the hexagonal lattice of pyramidal cell patches may underlie the discretization of grid spacing and orientation. In the continuous attractor network composed of interneurons, stellate and pyramidal cells, the hexagonal lattice of bump attractors is specifically aligned to the patch lattice under 22 conditions determined by the geometry of the patch lattice, while pyramidal cells exhibit synchrony to diverse extents. Given the bump attractor lattice in each module originates from those 22 scenarios, the experimental data on the grid spacing ratio and orientation difference between modules can be reproduced. This work recapitulates the patterns of grid spacing versus orientation in individual animals and reveals the correlation between microstructures and firing fields, providing a systems-level mechanism for grid modularity. Each module is modeled as a continuous attractor network with specific parameters The lattice of bump attractors is specifically aligned to the pyramidal patch lattice Twenty-two scenarios for the bump attractor lattice are proposed The grid spacing ratios and orientation differences are determined intrinsically
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17
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Chen CH, Hu JM, Chen SQ, Liu SM, Ding SL. Homotopic Commissural Projections of Area Prostriata in Rat and Mouse: Comparison With Presubiculum and Parasubiculum. Front Neural Circuits 2020; 14:605332. [PMID: 33324173 PMCID: PMC7724997 DOI: 10.3389/fncir.2020.605332] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Accepted: 10/26/2020] [Indexed: 11/17/2022] Open
Abstract
Area prostriata in primates has recently been found to play important roles in rapid detection and processing of peripheral visual, especially fast-moving visual information. The prostriata in rodents was not discovered until recently and its connectivity is largely unknown. As a part of our efforts to reveal brain-wide connections of the prostriata in rat and mouse, this study focuses on its commissural projections in order to understand the mechanisms underlying interhemispheric integration of information, especially from peripheral visual field. Using anterograde, retrograde and Cre-dependent tracing techniques, we find a unique commissural connection pattern of the prostriata: its layers 2-3 in both hemispheres form strong homotopic commissural connections with few heterotopic projections to bilateral medial entorhinal cortex. This projection pattern is in sharp contrast to that of the presubiculum and parasubiculum, two neighbor regions of the prostriata. The latter two structures project very strongly to bilateral medial entorhinal cortex and to their contralateral counterparts. Our results also suggest the prostriata is a distinct anatomical structure from the presubiculum and parasubiculum and probably plays differential roles in interhemispheric integration and the balancing of spatial information between two hemispheres.
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Affiliation(s)
- Chang-Hui Chen
- Key Laboratory of Neuroscience, School of Basic Medical Sciences, Institute of Neuroscience, The Second Affiliated Hospital, Guangzhou Medical University, Guangzhou, China
| | - Jin-Meng Hu
- Key Laboratory of Neuroscience, School of Basic Medical Sciences, Institute of Neuroscience, The Second Affiliated Hospital, Guangzhou Medical University, Guangzhou, China
| | - Sheng-Qiang Chen
- Key Laboratory of Neuroscience, School of Basic Medical Sciences, Institute of Neuroscience, The Second Affiliated Hospital, Guangzhou Medical University, Guangzhou, China
| | - Shi-Ming Liu
- Key Laboratory of Neuroscience, School of Basic Medical Sciences, Institute of Neuroscience, The Second Affiliated Hospital, Guangzhou Medical University, Guangzhou, China
| | - Song-Lin Ding
- Key Laboratory of Neuroscience, School of Basic Medical Sciences, Institute of Neuroscience, The Second Affiliated Hospital, Guangzhou Medical University, Guangzhou, China.,Allen Institute for Brain Science, Seattle, WA, United States
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18
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Ryan JD, Shen K, Kacollja A, Tian H, Griffiths J, Bezgin G, McIntosh AR. Modeling the influence of the hippocampal memory system on the oculomotor system. Netw Neurosci 2020; 4:217-233. [PMID: 32166209 PMCID: PMC7055646 DOI: 10.1162/netn_a_00120] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Accepted: 12/04/2019] [Indexed: 01/12/2023] Open
Abstract
Visual exploration is related to activity in the hippocampus (HC) and/or extended medial temporal lobe system (MTL), is influenced by stored memories, and is altered in amnesic cases. An extensive set of polysynaptic connections exists both within and between the HC and oculomotor systems such that investigating how HC responses ultimately influence neural activity in the oculomotor system, and the timing by which such neural modulation could occur, is not trivial. We leveraged TheVirtualBrain, a software platform for large-scale network simulations, to model the functional dynamics that govern the interactions between the two systems in the macaque cortex. Evoked responses following the stimulation of the MTL and some, but not all, subfields of the HC resulted in observable responses in oculomotor regions, including the frontal eye fields, within the time of a gaze fixation. Modeled lesions to some MTL regions slowed the dissipation of HC signal to oculomotor regions, whereas HC lesions generally did not affect the rapid MTL activity propagation to oculomotor regions. These findings provide a framework for investigating how information represented by the HC/MTL may influence the oculomotor system during a fixation and predict how HC lesions may affect visual exploration.
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Affiliation(s)
- Jennifer D Ryan
- Rotman Research Institute, Baycrest, Toronto, Ontario, Canada
| | - Kelly Shen
- Rotman Research Institute, Baycrest, Toronto, Ontario, Canada
| | - Arber Kacollja
- Rotman Research Institute, Baycrest, Toronto, Ontario, Canada
| | - Heather Tian
- Rotman Research Institute, Baycrest, Toronto, Ontario, Canada
| | - John Griffiths
- Rotman Research Institute, Baycrest, Toronto, Ontario, Canada
| | - Gleb Bezgin
- Montreal Neurological Institute, McGill University, Montreal, Quebec, Canada
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19
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Sanguinetti-Scheck JI, Brecht M. Home, head direction stability, and grid cell distortion. J Neurophysiol 2020; 123:1392-1406. [PMID: 32101492 PMCID: PMC7191526 DOI: 10.1152/jn.00518.2019] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
The home is a unique location in the life of humans and animals. In rats, home presents itself as a multicompartmental space that involves integrating navigation through subspaces. Here we embedded the laboratory rat’s home cage in the arena, while recording neurons in the animal’s parasubiculum and medial entorhinal cortex, two brain areas encoding the animal’s location and head direction. We found that head direction signals were unaffected by home cage presence or translocation. Head direction cells remain globally stable and have similar properties inside and outside the embedded home. We did not observe egocentric bearing encoding of the home cage. However, grid cells were distorted in the presence of the home cage. While they did not globally remap, single firing fields were translocated toward the home. These effects appeared to be geometrical in nature rather than a home-specific distortion and were not dependent on explicit behavioral use of the home cage during a hoarding task. Our work suggests that medial entorhinal cortex and parasubiculum do not remap after embedding the home, but local changes in grid cell activity overrepresent the embedded space location and might contribute to navigation in complex environments. NEW & NOTEWORTHY Neural findings in the field of spatial navigation come mostly from an abstract approach that separates the animal from even a minimally biological context. In this article we embed the home cage of the rat in the environment to address some of the complexities of natural navigation. We find no explicit home cage representation. While both head direction cells and grid cells remain globally stable, we find that embedded spaces locally distort grid cells.
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Affiliation(s)
| | - Michael Brecht
- Bernstein Center for Computational Neuroscience, Humboldt-Universität zu Berlin, Berlin, Germany.,NeuroCure Cluster of Excellence, Humboldt-Universität zu Berlin, Berlin, Germany
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20
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Fukawa A, Aizawa T, Yamakawa H, Eguchi Yairi I. Identifying Core Regions for Path Integration on Medial Entorhinal Cortex of Hippocampal Formation. Brain Sci 2020; 10:brainsci10010028. [PMID: 31948100 PMCID: PMC7016820 DOI: 10.3390/brainsci10010028] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2019] [Accepted: 12/31/2019] [Indexed: 12/31/2022] Open
Abstract
Path integration is one of the functions that support the self-localization ability of animals. Path integration outputs position information after an animal’s movement when initial-position and movement information is input. The core region responsible for this function has been identified as the medial entorhinal cortex (MEC), which is part of the hippocampal formation that constitutes the limbic system. However, a more specific core region has not yet been identified. This research aims to clarify the detailed structure at the cell-firing level in the core region responsible for path integration from fragmentarily accumulated experimental and theoretical findings by reviewing 77 papers. This research draws a novel diagram that describes the MEC, the hippocampus, and their surrounding regions by focusing on the MEC’s input/output (I/O) information. The diagram was created by summarizing the results of exhaustively scrutinizing the papers that are relative to the I/O relationship, the connection relationship, and cell position and firing pattern. From additional investigations, we show function information related to path integration, such as I/O information and the relationship between multiple functions. Furthermore, we constructed an algorithmic hypothesis on I/O information and path-integration calculation method from the diagram and the information of functions related to path integration. The algorithmic hypothesis is composed of regions related to path integration, the I/O relations between them, the calculation performed there, and the information representations (cell-firing pattern) in them. Results of examining the hypothesis confirmed that the core region responsible for path integration was either stellate cells in layer II or pyramidal cells in layer III of the MEC.
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Affiliation(s)
- Ayako Fukawa
- Graduate School of Science and Engineering, Sophia University, 7-1 Kioi-cho, Chiyoda-ku, Tokyo 102-8554, Japan;
- Correspondence: ; Tel.: +81-3-3238-3300
| | - Takahiro Aizawa
- Graduate School of Medicine and Faculty of Medicine, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan;
| | - Hiroshi Yamakawa
- The Whole Brain Architecture Initiative, a Specified Nonprofit Organization, Nishikoiwa 2-19-21, Edogawa-ku, Tokyo 133-0057, Japan;
- Dwango Co., Ltd., KABUKIZA TOWER, 4-12-15 Ginza, Chuo-ku, Tokyo 104-0061, Japan
| | - Ikuko Eguchi Yairi
- Graduate School of Science and Engineering, Sophia University, 7-1 Kioi-cho, Chiyoda-ku, Tokyo 102-8554, Japan;
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21
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Electrophysiological and Molecular Characterization of the Parasubiculum. J Neurosci 2019; 39:8860-8876. [PMID: 31548233 DOI: 10.1523/jneurosci.0796-19.2019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Revised: 08/30/2019] [Accepted: 09/04/2019] [Indexed: 11/21/2022] Open
Abstract
The parahippocampal region is thought to be critical for memory and spatial navigation. Within this region lies the parasubiculum, a small structure that exhibits strong theta modulation, contains functionally specialized cells, and projects to layer II of the medial entorhinal cortex (MEC). Thus, it is uniquely positioned to influence firing of spatially modulated cells in the MEC and play a key role in the internal representation of the external environment. However, the basic neuronal composition of the parasubiculum remains largely unknown, and its border with the MEC is often ambiguous. We combine electrophysiology and immunohistochemistry in adult mice (both sexes) to define first, the boundaries of the parasubiculum, and second, the major cell types found in this region. We find distinct differences in the colabeling of molecular markers between the parasubiculum and the MEC, allowing us to clearly separate the two structures. Moreover, we find distinct distribution patterns of different molecular markers within the parasubiculum, across both superficial-deep and DV axes. Using unsupervised cluster analysis, we find that neurons in the parasubiculum can be broadly separated into three clusters based on their electrophysiological properties, and that each cluster corresponds to a different molecular marker. We demonstrate that, while the parasubiculum aligns structurally to some to general cortical principals, it also shows divergent features in particular in contrast to the MEC. This work will form an important basis for future studies working to disentangle the circuitry underlying memory and spatial navigation functions of the parasubiculum.SIGNIFICANCE STATEMENT We identify the major neuron types in the parasubiculum using immunohistochemistry and electrophysiology, and determine their distribution throughout the parasubiculum. We find that the neuronal composition of the parasubiculum differs considerably compared with the neighboring medial entorhinal cortex. Both regions are involved in spatial navigation. Thus, our findings are of importance for unraveling the underlying circuitry of this process and for determining the role of the parasubiculum within this network.
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22
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Ohara S, Gianatti M, Itou K, Berndtsson CH, Doan TP, Kitanishi T, Mizuseki K, Iijima T, Tsutsui KI, Witter MP. Entorhinal Layer II Calbindin-Expressing Neurons Originate Widespread Telencephalic and Intrinsic Projections. Front Syst Neurosci 2019; 13:54. [PMID: 31680885 PMCID: PMC6803526 DOI: 10.3389/fnsys.2019.00054] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Accepted: 09/30/2019] [Indexed: 12/02/2022] Open
Abstract
In the present study we provide the first systematic and quantitative hodological study of the calbindin-expressing (CB+) principal neurons in layer II of the entorhinal cortex and compared the respective projections of the lateral and medial subdivisions of the entorhinal cortex. Using elaborate quantitative retrograde tracing, complemented by anterograde tracing, we report that the layer II CB+ population comprises neurons with diverse, mainly excitatory projections. At least half of them originate local intrinsic and commissural projections which distribute mainly to layer I and II. We further show that long-range CB+ projections from the two entorhinal subdivisions differ substantially in that MEC projections mainly target field CA1 of the hippocampus, whereas LEC CB+ projections distribute much more widely to a substantial number of known forebrain targets. This connectional difference between the CB+ populations in LEC and MEC is reminiscent of the overall projection pattern of the two entorhinal subdivisions.
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Affiliation(s)
- Shinya Ohara
- Kavli Institute for Systems Neuroscience, Center for Computational Neuroscience, Egil and Pauline Braathen and Fred Kavli Centre for Cortical Microcircuits, Norwegian University of Science and Technology (NTNU), Trondheim, Norway.,Laboratory of Systems Neuroscience, Graduate School of Life Sciences, Tohoku University, Sendai, Japan
| | - Michele Gianatti
- Kavli Institute for Systems Neuroscience, Center for Computational Neuroscience, Egil and Pauline Braathen and Fred Kavli Centre for Cortical Microcircuits, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
| | - Kazuki Itou
- Laboratory of Systems Neuroscience, Graduate School of Life Sciences, Tohoku University, Sendai, Japan
| | - Christin H Berndtsson
- Kavli Institute for Systems Neuroscience, Center for Computational Neuroscience, Egil and Pauline Braathen and Fred Kavli Centre for Cortical Microcircuits, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
| | - Thanh P Doan
- Kavli Institute for Systems Neuroscience, Center for Computational Neuroscience, Egil and Pauline Braathen and Fred Kavli Centre for Cortical Microcircuits, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
| | - Takuma Kitanishi
- Department of Physiology, Graduate School of Medicine, Osaka City University, Osaka, Japan
| | - Kenji Mizuseki
- Department of Physiology, Graduate School of Medicine, Osaka City University, Osaka, Japan
| | - Toshio Iijima
- Laboratory of Systems Neuroscience, Graduate School of Life Sciences, Tohoku University, Sendai, Japan
| | - Ken-Ichiro Tsutsui
- Laboratory of Systems Neuroscience, Graduate School of Life Sciences, Tohoku University, Sendai, Japan
| | - Menno P Witter
- Kavli Institute for Systems Neuroscience, Center for Computational Neuroscience, Egil and Pauline Braathen and Fred Kavli Centre for Cortical Microcircuits, Norwegian University of Science and Technology (NTNU), Trondheim, Norway
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23
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Valero M, English DF. Head-mounted approaches for targeting single-cells in freely moving animals. J Neurosci Methods 2019; 326:108397. [DOI: 10.1016/j.jneumeth.2019.108397] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Revised: 07/30/2019] [Accepted: 08/06/2019] [Indexed: 12/11/2022]
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24
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Doan TP, Lagartos-Donate MJ, Nilssen ES, Ohara S, Witter MP. Convergent Projections from Perirhinal and Postrhinal Cortices Suggest a Multisensory Nature of Lateral, but Not Medial, Entorhinal Cortex. Cell Rep 2019; 29:617-627.e7. [DOI: 10.1016/j.celrep.2019.09.005] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2019] [Revised: 08/06/2019] [Accepted: 08/30/2019] [Indexed: 10/25/2022] Open
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25
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Sullenberger T, Don H, Kumar SS. Functional Connectivity of the Parasubiculum and Its Role in Temporal Lobe Epilepsy. Neuroscience 2019; 410:217-238. [PMID: 31121261 DOI: 10.1016/j.neuroscience.2019.05.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Revised: 04/22/2019] [Accepted: 05/05/2019] [Indexed: 10/26/2022]
Abstract
Temporal lobe epilepsy (TLE) is the commonest of adult epilepsies, often refractory to antiepileptic medications, whose prevention and treatment rely on understanding basic pathophysiological mechanisms in interlinked structures of the temporal lobe. The medial entorhinal area (MEA) is affected in TLE but mechanisms underlying hyperexcitability of MEA neurons require further elucidation. Previous studies have examined the role of the presubiculum (PrS) in mediating MEA pathophysiology but not the juxtaposed parasubiculum (Par). Here, we report on an electrophysiological assessment of the cells and circuits of the Par, their excitability under normal and epileptic conditions, and alterations in functional connectivity with neighboring PrS and MEA using the rat pilocarpine model of TLE. We show that Par, unlike the cell heterogeneous PrS, has a single dominant neuronal population whose excitability under epileptic conditions is altered by changes in both intrinsic properties and synaptic drive. These neurons experience significant reductions in synaptic inhibition and perish under chronic epileptic conditions. Connectivity between brain regions was deduced through changes in excitatory and inhibitory synaptic drive to neurons recorded in one region upon focal application of glutamate followed by NBQX to neurons in another using a microfluidic technique called CESOP and TLE-related circuit reorganization was assessed using data from normal and epileptic animals. The region-specific changes in Par and neighboring PrS and MEA together with their unexpected interactions are of significance in identifying ictogenic cells and circuits within the parahippocampal region and in unraveling pathophysiological mechanisms underlying TLE.
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Affiliation(s)
- Thomas Sullenberger
- Department of Biomedical Sciences, College of Medicine & Program in Neuroscience, Florida State University, 1115 W. Call Street, Tallahassee, FL 32306-4300, United States of America
| | - Hershel Don
- Department of Biomedical Sciences, College of Medicine & Program in Neuroscience, Florida State University, 1115 W. Call Street, Tallahassee, FL 32306-4300, United States of America
| | - Sanjay S Kumar
- Department of Biomedical Sciences, College of Medicine & Program in Neuroscience, Florida State University, 1115 W. Call Street, Tallahassee, FL 32306-4300, United States of America.
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26
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Carter F, Chapman CA. Serotonin 5-HT 1A Receptor-Mediated Reduction of Excitatory Synaptic Transmission in Layers II/III of the Parasubiculum. Neuroscience 2019; 406:325-332. [PMID: 30902681 DOI: 10.1016/j.neuroscience.2019.03.024] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2019] [Revised: 02/25/2019] [Accepted: 03/11/2019] [Indexed: 12/26/2022]
Abstract
Serotonin (5-HT) has important effects on cognitive function within the hippocampal region where it modulates membrane potential and excitatory and inhibitory synaptic transmission. Here, we investigated how 5-HT modulates excitatory synaptic strength in layers II/III of the parasubiculum in rat brain slices. Bath-application of 1 or 10 μM 5-HT resulted in a strong, dose-dependent, and reversible reduction in the amplitude of field excitatory postsynaptic potentials (fEPSPs) recorded in the parasubiculum. The 5-HT reuptake blocker citalopram (10 μM) also reduced fEPSP amplitudes, indicating that 5-HT released within the slice inhibits synaptic transmission. The reduction of fEPSPs induced by 5-HT was blocked by the 5-HT1A receptor blocker NAN-190 (10 μM), but not by the 5-HT7 receptor blocker SB-269970 (10 μM). Moreover, the 5-HT1A agonist 8-OH-DPAT induced a reduction of fEPSP amplitude similar to that induced by 5-HT. The reduction was prevented by the 5-HT1A receptor blocker NAN-190. The reduction in fEPSPs induced by either 5-HT or by 8-OH-DPAT was accompanied by an increase in paired-pulse ratio, suggesting that it is due mainly to reduced glutamate release. Our data suggest that the effects of serotonin on cognitive function may depend in part upon a 5-HT1A-mediated reduction of excitatory synaptic transmission in the parasubiculum. This may also affect synaptic processing in the entorhinal cortex, which receives the major output projection of the parasubiculum.
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Affiliation(s)
- Francis Carter
- Center for Studies in Behavioral Neurobiology, Department of Psychology, Concordia University, Montréal, Québec, Canada H4B 1R6
| | - C Andrew Chapman
- Center for Studies in Behavioral Neurobiology, Department of Psychology, Concordia University, Montréal, Québec, Canada H4B 1R6.
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27
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Zheng F, Cui D, Zhang L, Zhang S, Zhao Y, Liu X, Liu C, Li Z, Zhang D, Shi L, Liu Z, Hou K, Lu W, Yin T, Qiu J. The Volume of Hippocampal Subfields in Relation to Decline of Memory Recall Across the Adult Lifespan. Front Aging Neurosci 2018; 10:320. [PMID: 30364081 PMCID: PMC6191512 DOI: 10.3389/fnagi.2018.00320] [Citation(s) in RCA: 55] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Accepted: 09/24/2018] [Indexed: 12/27/2022] Open
Abstract
Background: The hippocampus is an important limbic structure closely related to memory function. However, few studies have focused on the association between hippocampal subfields and age-related memory decline. We investigated the volume alterations of hippocampal subfields at different ages and assessed the correlations with Immediate and Delayed recall abilities. Materials and Methods: A total of 275 participants aged 20-89 years were classified into 4 groups: Young, 20-35 years; Middle-early, 36-50 years; Middle-late, 51-65 years; Old, 66-89 years. All data were acquired from the Dallas Lifespan Brain Study (DLBS). The volumes of hippocampal subfields were obtained using Freesurfer software. Analysis of covariance (ANCOVA) was performed to analyze alterations of subfield volumes among the 4 groups, and multiple comparisons between groups were performed using the Bonferroni method. Spearman correlation with false discovery rate correction was used to investigate the relationship between memory recall scores and hippocampal subfield volumes. Results: Apart from no significant difference in the left parasubiculum (P = 0.269) and a slight difference in the right parasubiculum (P = 0.022), the volumes of other hippocampal subfields were significantly different across the adult lifespan (P < 0.001). The hippocampal fissure volume was increased in the Old group, while volumes for other subfields decreased. In addition, Immediate recall scores were associated with volumes of the bilateral molecular layer, granule cell layer of the dentate gyrus (GC-DG), cornus ammonis (CA) 1, CA2/3, CA4, left fimbria and hippocampal amygdala transition area (HATA), and right fissure (P < 0.05). Delayed recall scores were associated with the bilateral molecular layer, GC-DG, CA2/3 and CA4; left tail, presubiculum, CA1, subiculum, fimbria and HATA (P < 0.05). Conclusion: The parasubiculum volume was not significantly different across the adult lifespan, while atrophy in dementia patients in some studies. Based on these findings, we speculate that volume changes in this region might be considered as a biomarker for dementia disorders. Additionally, several hippocampal subfield volumes were significantly associated with memory scores, further highlighting the key role of the hippocampus in age-related memory decline. These regions could be used to assess the risk of memory decline across the adult lifespan.
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Affiliation(s)
- Fenglian Zheng
- Medical Engineering and Technology Research Center, Taishan Medical University, Taian, China
- Imaging-X Joint Laboratory, Taian, China
- College of Radiology, Taishan Medical University, Taian, China
| | - Dong Cui
- College of Radiology, Taishan Medical University, Taian, China
- Institute of Biomedical Engineering, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin, China
| | - Li Zhang
- Medical Engineering and Technology Research Center, Taishan Medical University, Taian, China
- Imaging-X Joint Laboratory, Taian, China
- College of Radiology, Taishan Medical University, Taian, China
| | - Shitong Zhang
- Medical Engineering and Technology Research Center, Taishan Medical University, Taian, China
- Imaging-X Joint Laboratory, Taian, China
- College of Radiology, Taishan Medical University, Taian, China
- College of Mechanical and Electronic Engineering, Shandong University of Science and Technology, Qingdao, China
| | - Yue Zhao
- Medical Engineering and Technology Research Center, Taishan Medical University, Taian, China
- Imaging-X Joint Laboratory, Taian, China
- College of Radiology, Taishan Medical University, Taian, China
- College of Mechanical and Electronic Engineering, Shandong University of Science and Technology, Qingdao, China
| | - Xiaojing Liu
- Medical Engineering and Technology Research Center, Taishan Medical University, Taian, China
- Imaging-X Joint Laboratory, Taian, China
- College of Radiology, Taishan Medical University, Taian, China
| | - Chunhua Liu
- School of Basic Medical Sciences, Taishan Medical University, Taian, China
| | - Zhengmei Li
- Medical Engineering and Technology Research Center, Taishan Medical University, Taian, China
- Imaging-X Joint Laboratory, Taian, China
- College of Radiology, Taishan Medical University, Taian, China
| | - Dongsheng Zhang
- Medical Engineering and Technology Research Center, Taishan Medical University, Taian, China
- Imaging-X Joint Laboratory, Taian, China
- College of Radiology, Taishan Medical University, Taian, China
| | - Liting Shi
- Medical Engineering and Technology Research Center, Taishan Medical University, Taian, China
- Imaging-X Joint Laboratory, Taian, China
- College of Radiology, Taishan Medical University, Taian, China
| | - Zhipeng Liu
- Institute of Biomedical Engineering, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin, China
| | - Kun Hou
- Medical Engineering and Technology Research Center, Taishan Medical University, Taian, China
- Imaging-X Joint Laboratory, Taian, China
- College of Radiology, Taishan Medical University, Taian, China
| | - Wen Lu
- Medical Engineering and Technology Research Center, Taishan Medical University, Taian, China
- Imaging-X Joint Laboratory, Taian, China
- College of Radiology, Taishan Medical University, Taian, China
| | - Tao Yin
- Institute of Biomedical Engineering, Chinese Academy of Medical Sciences and Peking Union Medical College, Tianjin, China
| | - Jianfeng Qiu
- Medical Engineering and Technology Research Center, Taishan Medical University, Taian, China
- Imaging-X Joint Laboratory, Taian, China
- College of Radiology, Taishan Medical University, Taian, China
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28
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Naumann RK, Preston-Ferrer P, Brecht M, Burgalossi A. Structural modularity and grid activity in the medial entorhinal cortex. J Neurophysiol 2018. [PMID: 29513150 DOI: 10.1152/jn.00574.2017] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Following the groundbreaking discovery of grid cells, the medial entorhinal cortex (MEC) has become the focus of intense anatomical, physiological, and computational investigations. Whether and how grid activity maps onto cell types and cortical architecture is still an open question. Fundamental similarities in microcircuits, function, and connectivity suggest a homology between rodent MEC and human posteromedial entorhinal cortex. Both are specialized for spatial processing and display similar cellular organization, consisting of layer 2 pyramidal/calbindin cell patches superimposed on scattered stellate neurons. Recent data indicate the existence of a further nonoverlapping modular system (zinc patches) within the superficial MEC layers. Zinc and calbindin patches have been shown to receive largely segregated inputs from the presubiculum and parasubiculum. Grid cells are also clustered in the MEC, and we discuss possible structure-function schemes on how grid activity could map onto cortical patch systems. We hypothesize that in the superficial layers of the MEC, anatomical location can be predictive of function; thus relating functional properties and neuronal morphologies to the cortical modules will be necessary for resolving how grid activity maps onto cortical architecture. Imaging or cell identification approaches in freely moving animals will be required for testing this hypothesis.
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Affiliation(s)
- Robert K Naumann
- Bernstein Center for Computational Neuroscience, Humboldt University of Berlin , Berlin , Germany.,Max-Planck-Institute for Brain Research, Frankfurt am Main , Germany.,Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen University Town, Nanshan District, Shenzhen , China
| | | | - Michael Brecht
- Bernstein Center for Computational Neuroscience, Humboldt University of Berlin , Berlin , Germany.,German Center for Neurodegenerative Diseases , Berlin , Germany
| | - Andrea Burgalossi
- Werner-Reichardt Centre for Integrative Neuroscience , Tübingen , Germany
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29
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Lauer SM, Schneeweiß U, Brecht M, Ray S. Visualization of Cortical Modules in Flattened Mammalian Cortices. J Vis Exp 2018. [PMID: 29443106 DOI: 10.3791/56992] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The cortex of mammalian brains is parcellated into distinct substructures or modules. Cortical modules typically lie parallel to the cortical sheet, and can be delineated by certain histochemical and immunohistochemical methods. In this study, we highlight a method to isolate the cortex from mammalian brains and flatten them to obtain sections parallel to the cortical sheet. We further highlight selected histochemical and immunohistochemical methods to process these flattened tangential sections to visualize cortical modules. In the somatosensory cortex of various mammals, we perform cytochrome oxidase histochemistry to reveal body maps or cortical modules representing different parts of the body of the animal. In the medial entorhinal cortex, an area where grid cells are generated, we utilize immunohistochemical methods to highlight modules of genetically determined neurons which are arranged in a grid-pattern in the cortical sheet across several species. Overall, we provide a framework to isolate and prepare layer-wise flattened cortical sections, and visualize cortical modules using histochemical and immunohistochemical methods in a wide variety of mammalian brains.
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Affiliation(s)
- Simon M Lauer
- Bernstein Center for Computational Neuroscience, Humboldt University of Berlin
| | - Undine Schneeweiß
- Bernstein Center for Computational Neuroscience, Humboldt University of Berlin
| | - Michael Brecht
- Bernstein Center for Computational Neuroscience, Humboldt University of Berlin; NeuroCure Cluster of Excellence; German Center for Neurodegenerative Diseases
| | - Saikat Ray
- Bernstein Center for Computational Neuroscience, Humboldt University of Berlin;
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30
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Averill CL, Satodiya RM, Scott JC, Wrocklage KM, Schweinsburg B, Averill LA, Akiki TJ, Amoroso T, Southwick SM, Krystal JH, Abdallah CG. Posttraumatic Stress Disorder and Depression Symptom Severities Are Differentially Associated With Hippocampal Subfield Volume Loss in Combat Veterans. ACTA ACUST UNITED AC 2017. [PMID: 29520395 PMCID: PMC5839647 DOI: 10.1177/2470547017744538] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Background Two decades of human neuroimaging research have associated volume reductions
in the hippocampus with posttraumatic stress disorder. However, little is
known about the distribution of volume loss across hippocampal subfields.
Recent advances in neuroimaging methods have made it possible to accurately
delineate 10 gray matter hippocampal subfields. Here, we apply a volumetric
analysis of hippocampal subfields to data from a group of combat-exposed
Veterans. Method Veterans (total, n = 68, posttraumatic stress disorder, n = 36; combat
control, n = 32) completed high-resolution structural magnetic resonance
imaging. Based on previously validated methods, hippocampal subfield volume
measurements were conducted using FreeSurfer 6.0. The Clinician-Administered
PTSD Scale assessed posttraumatic stress disorder symptom severity; Beck
Depression Inventory assessed depressive symptom severity. Controlling for
age and intracranial volume, partial correlation analysis examined the
relationship between hippocampal subfields and symptom severity. Correction
for multiple comparisons was performed using false discovery rate. Gender,
intelligence, combat severity, comorbid anxiety, alcohol/substance use
disorder, and medication status were investigated as potential
confounds. Results In the whole sample, total hippocampal volume
negatively correlated with Clinician-Administered PTSD Scale and Beck Depression Inventory scores. Of the 10
hippocampal subfields, Clinician-Administered PTSD Scale symptom severity
negatively correlated with the hippocampus–amygdala
transition area (HATA). Beck Depression Inventory scores
negatively correlated with dentate gyrus, cornu ammonis 4 (CA4), HATA,
CA2/3, molecular layer, and CA1. Follow-up analysis limited to the
posttraumatic stress disorder group showed a negative correlation between
Clinician-Administered PTSD Scale symptom severity and each of HATA, CA2/3,
molecular layer, and CA4. Conclusion This study provides the first evidence relating posttraumatic stress disorder
and depression symptoms to abnormalities in the HATA, an anterior
hippocampal region highly connected to prefrontal-amygdala circuitry.
Notably, dentate gyrus abnormalities were associated with depression
severity but not posttraumatic stress disorder symptoms. Future confirmatory
studies should determine the extent to which dentate gyrus volume can
differentiate between posttraumatic stress disorder- and depression-related
pathophysiology.
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Affiliation(s)
- Christopher L Averill
- National Center for PTSD, Clinical Neurosciences Division, US Department of Veterans Affairs, West Haven, CT, USA.,Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
| | - Ritvij M Satodiya
- National Center for PTSD, Clinical Neurosciences Division, US Department of Veterans Affairs, West Haven, CT, USA.,Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
| | - J Cobb Scott
- Department of Psychiatry, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.,VISN4 Mental Illness Research, Education, and Clinical Center, Philadelphia VA Medical Center, Philadelphia, PA, USA
| | - Kristen M Wrocklage
- National Center for PTSD, Clinical Neurosciences Division, US Department of Veterans Affairs, West Haven, CT, USA.,Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA.,Gaylord Specialty Healthcare, Department of Psychology, Wallingford, CT, USA
| | - Brian Schweinsburg
- National Center for PTSD, Clinical Neurosciences Division, US Department of Veterans Affairs, West Haven, CT, USA.,Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
| | - Lynnette A Averill
- National Center for PTSD, Clinical Neurosciences Division, US Department of Veterans Affairs, West Haven, CT, USA.,Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
| | - Teddy J Akiki
- National Center for PTSD, Clinical Neurosciences Division, US Department of Veterans Affairs, West Haven, CT, USA.,Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
| | - Timothy Amoroso
- National Center for PTSD, Clinical Neurosciences Division, US Department of Veterans Affairs, West Haven, CT, USA.,Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
| | - Steven M Southwick
- National Center for PTSD, Clinical Neurosciences Division, US Department of Veterans Affairs, West Haven, CT, USA.,Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
| | - John H Krystal
- National Center for PTSD, Clinical Neurosciences Division, US Department of Veterans Affairs, West Haven, CT, USA.,Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
| | - Chadi G Abdallah
- National Center for PTSD, Clinical Neurosciences Division, US Department of Veterans Affairs, West Haven, CT, USA.,Department of Psychiatry, Yale University School of Medicine, New Haven, CT, USA
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31
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Transformation of the head-direction signal into a spatial code. Nat Commun 2017; 8:1752. [PMID: 29170377 PMCID: PMC5700966 DOI: 10.1038/s41467-017-01908-3] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Accepted: 10/24/2017] [Indexed: 12/18/2022] Open
Abstract
Animals integrate multiple sensory inputs to successfully navigate in their environments. Head direction (HD), boundary vector, grid and place cells in the entorhinal-hippocampal network form the brain’s navigational system that allows to identify the animal’s current location, but how the functions of these specialized neuron types are acquired remain to be understood. Here we report that activity of HD neurons is influenced by the ambulatory constraints imposed upon the animal by the boundaries of the explored environment, leading to spurious spatial information. However, in the post-subiculum, the main cortical stage of HD signal processing, HD neurons convey true spatial information in the form of border modulated activity through the integration of additional sensory modalities relative to egocentric position, unlike their driving thalamic inputs. These findings demonstrate how the combination of HD and egocentric information can be transduced into a spatial code. A cognitive map of space must integrate allocentric cues such as head direction (HD) with various egocentric cues. Here the authors report that anterior thalamic (ADn) neurons encode a pure HD signal, while neurons in post-subiculum represent a conjunction of HD and egocentric cues such as body posture with respect to environment boundaries.
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32
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D’Albis T, Kempter R. A single-cell spiking model for the origin of grid-cell patterns. PLoS Comput Biol 2017; 13:e1005782. [PMID: 28968386 PMCID: PMC5638623 DOI: 10.1371/journal.pcbi.1005782] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2017] [Revised: 10/12/2017] [Accepted: 09/18/2017] [Indexed: 11/19/2022] Open
Abstract
Spatial cognition in mammals is thought to rely on the activity of grid cells in the entorhinal cortex, yet the fundamental principles underlying the origin of grid-cell firing are still debated. Grid-like patterns could emerge via Hebbian learning and neuronal adaptation, but current computational models remained too abstract to allow direct confrontation with experimental data. Here, we propose a single-cell spiking model that generates grid firing fields via spike-rate adaptation and spike-timing dependent plasticity. Through rigorous mathematical analysis applicable in the linear limit, we quantitatively predict the requirements for grid-pattern formation, and we establish a direct link to classical pattern-forming systems of the Turing type. Our study lays the groundwork for biophysically-realistic models of grid-cell activity.
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Affiliation(s)
- Tiziano D’Albis
- Institute for Theoretical Biology, Department of Biology, Humboldt-Universität zu Berlin, Berlin, Germany
| | - Richard Kempter
- Institute for Theoretical Biology, Department of Biology, Humboldt-Universität zu Berlin, Berlin, Germany
- Bernstein Center for Computational Neuroscience Berlin, Berlin, Germany
- Einstein Center for Neurosciences Berlin, Berlin, Germany
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33
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Ray S, Burgalossi A, Brecht M, Naumann RK. Complementary Modular Microcircuits of the Rat Medial Entorhinal Cortex. Front Syst Neurosci 2017; 11:20. [PMID: 28443003 PMCID: PMC5385340 DOI: 10.3389/fnsys.2017.00020] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2017] [Accepted: 03/24/2017] [Indexed: 11/13/2022] Open
Abstract
The parahippocampal region is organized into different areas, with the medial entorhinal cortex (MEC), presubiculum and parasubiculum prominent in spatial memory. Here, we also describe a region at the extremity of the MEC and bordering the subicular complex, the medial-most part of the entorhinal cortex. While the subdivisions of hippocampus proper form more or less continuous cell sheets, the superficial layers of the parahippocampal region have a distinct modular architecture. We investigate the spatial distribution, laminar position, and putative connectivity of zinc-positive modules in layer 2 of the MEC of rats and relate them to the calbindin-positive patches previously described in the entorhinal cortex. We found that the zinc-positive modules are complementary to the previously described calbindin-positive patches. We also found that inputs from the presubiculum are directed toward the zinc-positive modules while the calbindin-positive patches received inputs from the parasubiculum. Notably, the dendrites of neurons from layers 3 and 5, positive for Purkinje Cell Protein 4 expression, overlap with the zinc modules. Our data thus indicate that these two complementary modular systems, the calbindin patches and zinc modules, are part of parallel information streams in the hippocampal formation.
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Affiliation(s)
- Saikat Ray
- Bernstein Center for Computational Neuroscience, Humboldt University of BerlinBerlin, Germany
| | - Andrea Burgalossi
- Werner-Reichardt Centre for Integrative NeuroscienceTübingen, Germany
| | - Michael Brecht
- Bernstein Center for Computational Neuroscience, Humboldt University of BerlinBerlin, Germany
- German Center for Neurodegenerative DiseasesBerlin, Germany
| | - Robert K. Naumann
- Bernstein Center for Computational Neuroscience, Humboldt University of BerlinBerlin, Germany
- Max-Planck-Institute for Brain ResearchFrankfurt, Germany
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34
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Diamantaki M, Frey M, Berens P, Preston-Ferrer P, Burgalossi A. Sparse activity of identified dentate granule cells during spatial exploration. eLife 2016; 5. [PMID: 27692065 PMCID: PMC5077296 DOI: 10.7554/elife.20252] [Citation(s) in RCA: 96] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Accepted: 10/01/2016] [Indexed: 01/20/2023] Open
Abstract
In the dentate gyrus - a key component of spatial memory circuits - granule cells (GCs) are known to be morphologically diverse and to display heterogeneous activity profiles during behavior. To resolve structure-function relationships, we juxtacellularly recorded and labeled single GCs in freely moving rats. We found that the vast majority of neurons were silent during exploration. Most active GCs displayed a characteristic spike waveform, fired at low rates and showed spatial activity. Primary dendritic parameters were sufficient for classifying neurons as active or silent with high accuracy. Our data thus support a sparse coding scheme in the dentate gyrus and provide a possible link between structural and functional heterogeneity among the GC population.
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Affiliation(s)
- Maria Diamantaki
- Werner-Reichardt Centre for Integrative Neuroscience, University of Tübingen, Tübingen, Germany.,Graduate Training Centre of Neuroscience - IMPRS, University of Tübingen, Tübingen, Germany
| | - Markus Frey
- Werner-Reichardt Centre for Integrative Neuroscience, University of Tübingen, Tübingen, Germany
| | - Philipp Berens
- Werner-Reichardt Centre for Integrative Neuroscience, University of Tübingen, Tübingen, Germany.,Institute for Ophthalmic Research, University of Tübingen, Tübingen, Germany.,Bernstein Centre for Computational Neuroscience, University of Tübingen, Tübingen, Germany
| | - Patricia Preston-Ferrer
- Werner-Reichardt Centre for Integrative Neuroscience, University of Tübingen, Tübingen, Germany
| | - Andrea Burgalossi
- Werner-Reichardt Centre for Integrative Neuroscience, University of Tübingen, Tübingen, Germany
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35
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Cell Type-Specific Differences in Spike Timing and Spike Shape in the Rat Parasubiculum and Superficial Medial Entorhinal Cortex. Cell Rep 2016; 16:1005-1015. [PMID: 27425616 PMCID: PMC4967475 DOI: 10.1016/j.celrep.2016.06.057] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Revised: 05/04/2016] [Accepted: 06/12/2016] [Indexed: 01/05/2023] Open
Abstract
The medial entorhinal cortex (MEC) and the adjacent parasubiculum are known for their elaborate spatial discharges (grid cells, border cells, etc.) and the precessing of spikes relative to the local field potential. We know little, however, about how spatio-temporal firing patterns map onto cell types. We find that cell type is a major determinant of spatio-temporal discharge properties. Parasubicular neurons and MEC layer 2 (L2) pyramids have shorter spikes, discharge spikes in bursts, and are theta-modulated (rhythmic, locking, skipping), but spikes phase-precess only weakly. MEC L2 stellates and layer 3 (L3) neurons have longer spikes, do not discharge in bursts, and are weakly theta-modulated (non-rhythmic, weakly locking, rarely skipping), but spikes steeply phase-precess. The similarities between MEC L3 neurons and MEC L2 stellates on one hand and parasubicular neurons and MEC L2 pyramids on the other hand suggest two distinct streams of temporal coding in the parahippocampal cortex. We find cell type-specific differences in spike shape, burstiness, and phase precession In vivo cell type specificity does not match predictions from previous in vitro studies Anatomical identity is a major determinant of spike patterns in the parahippocampal cortex
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Preston-Ferrer P, Coletta S, Frey M, Burgalossi A. Anatomical organization of presubicular head-direction circuits. eLife 2016; 5. [PMID: 27282390 PMCID: PMC4927294 DOI: 10.7554/elife.14592] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Accepted: 06/09/2016] [Indexed: 11/18/2022] Open
Abstract
Neurons coding for head-direction are crucial for spatial navigation. Here we explored the cellular basis of head-direction coding in the rat dorsal presubiculum (PreS). We found that layer2 is composed of two principal cell populations (calbindin-positive and calbindin-negative neurons) which targeted the contralateral PreS and retrosplenial cortex, respectively. Layer3 pyramidal neurons projected to the medial entorhinal cortex (MEC). By juxtacellularly recording PreS neurons in awake rats during passive-rotation, we found that head-direction responses were preferentially contributed by layer3 pyramidal cells, whose long-range axons branched within layer3 of the MEC. In contrast, layer2 neurons displayed distinct spike-shapes, were not modulated by head-direction but rhythmically-entrained by theta-oscillations. Fast-spiking interneurons showed only weak directionality and theta-rhythmicity, but were significantly modulated by angular velocity. Our data thus indicate that PreS neurons differentially contribute to head-direction coding, and point to a cell-type- and layer-specific routing of directional and non-directional information to downstream cortical targets. DOI:http://dx.doi.org/10.7554/eLife.14592.001
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Affiliation(s)
| | - Stefano Coletta
- Werner-Reichardt Centre for Integrative Neuroscience, Tübingen, Germany
| | - Markus Frey
- Werner-Reichardt Centre for Integrative Neuroscience, Tübingen, Germany
| | - Andrea Burgalossi
- Werner-Reichardt Centre for Integrative Neuroscience, Tübingen, Germany
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Ray S, Brecht M. Structural development and dorsoventral maturation of the medial entorhinal cortex. eLife 2016; 5:e13343. [PMID: 27036175 PMCID: PMC4876644 DOI: 10.7554/elife.13343] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2015] [Accepted: 03/27/2016] [Indexed: 12/11/2022] Open
Abstract
We investigated the structural development of superficial-layers of medial entorhinal cortex and parasubiculum in rats. The grid-layout and cholinergic-innervation of calbindin-positive pyramidal-cells in layer-2 emerged around birth while reelin-positive stellate-cells were scattered throughout development. Layer-3 and parasubiculum neurons had a transient calbindin-expression, which declined with age. Early postnatally, layer-2 pyramidal but not stellate-cells co-localized with doublecortin - a marker of immature neurons - suggesting delayed functional-maturation of pyramidal-cells. Three observations indicated a dorsal-to-ventral maturation of entorhinal cortex and parasubiculum: (i) calbindin-expression in layer-3 neurons decreased progressively from dorsal-to-ventral, (ii) doublecortin in layer-2 calbindin-positive-patches disappeared dorsally before ventrally, and (iii) wolframin-expression emerged earlier in dorsal than ventral parasubiculum. The early appearance of calbindin-pyramidal-grid-organization in layer-2 suggests that this pattern is instructed by genetic information rather than experience. Superficial-layer-microcircuits mature earlier in dorsal entorhinal cortex, where small spatial-scales are represented. Maturation of ventral-entorhinal-microcircuits - representing larger spatial-scales - follows later around the onset of exploratory behavior.
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Affiliation(s)
- Saikat Ray
- Bernstein Center for Computational
Neuroscience, Humboldt University of
Berlin, Berlin, Germany
| | - Michael Brecht
- Bernstein Center for Computational
Neuroscience, Humboldt University of
Berlin, Berlin, Germany
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Abstract
The medial entorhinal cortex (MEC) creates a neural representation of space through a set of functionally dedicated cell types: grid cells, border cells, head direction cells, and speed cells. Grid cells, the most abundant functional cell type in the MEC, have hexagonally arranged firing fields that tile the surface of the environment. These cells were discovered only in 2005, but after 10 years of investigation, we are beginning to understand how they are organized in the MEC network, how their periodic firing fields might be generated, how they are shaped by properties of the environment, and how they interact with the rest of the MEC network. The aim of this review is to summarize what we know about grid cells and point out where our knowledge is still incomplete.
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Affiliation(s)
- David C Rowland
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation, Norwegian University of Science and Technology, 7491 Trondheim, Norway; , , ,
| | - Yasser Roudi
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation, Norwegian University of Science and Technology, 7491 Trondheim, Norway; , , ,
| | - May-Britt Moser
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation, Norwegian University of Science and Technology, 7491 Trondheim, Norway; , , ,
| | - Edvard I Moser
- Kavli Institute for Systems Neuroscience and Centre for Neural Computation, Norwegian University of Science and Technology, 7491 Trondheim, Norway; , , ,
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