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Delavari F, Sandini C, Kojovic N, Saccaro LF, Eliez S, Van De Ville D, Bolton TAW. Thalamic contributions to psychosis susceptibility: Evidence from co-activation patterns accounting for intra-seed spatial variability (μCAPs). Hum Brain Mapp 2024; 45:e26649. [PMID: 38520364 PMCID: PMC10960557 DOI: 10.1002/hbm.26649] [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: 07/23/2023] [Revised: 02/20/2024] [Accepted: 02/22/2024] [Indexed: 03/25/2024] Open
Abstract
The temporal variability of the thalamus in functional networks may provide valuable insights into the pathophysiology of schizophrenia. To address the complexity of the role of the thalamic nuclei in psychosis, we introduced micro-co-activation patterns (μCAPs) and employed this method on the human genetic model of schizophrenia 22q11.2 deletion syndrome (22q11.2DS). Participants underwent resting-state functional MRI and a data-driven iterative process resulting in the identification of six whole-brain μCAPs with specific activity patterns within the thalamus. Unlike conventional methods, μCAPs extract dynamic spatial patterns that reveal partially overlapping and non-mutually exclusive functional subparts. Thus, the μCAPs method detects finer foci of activity within the initial seed region, retaining valuable and clinically relevant temporal and spatial information. We found that a μCAP showing co-activation of the mediodorsal thalamus with brain-wide cortical regions was expressed significantly less frequently in patients with 22q11.2DS, and its occurrence negatively correlated with the severity of positive psychotic symptoms. Additionally, activity within the auditory-visual cortex and their respective geniculate nuclei was expressed in two different μCAPs. One of these auditory-visual μCAPs co-activated with salience areas, while the other co-activated with the default mode network (DMN). A significant shift of occurrence from the salience+visuo-auditory-thalamus to the DMN + visuo-auditory-thalamus μCAP was observed in patients with 22q11.2DS. Thus, our findings support existing research on the gatekeeping role of the thalamus for sensory information in the pathophysiology of psychosis and revisit the evidence of geniculate nuclei hyperconnectivity with the audio-visual cortex in 22q11.2DS in the context of dynamic functional connectivity, seen here as the specific hyper-occurrence of these circuits with the task-negative brain networks.
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Affiliation(s)
- Farnaz Delavari
- Developmental Imaging and Psychopathology LaboratoryUniversity of Geneva School of MedicineGenevaSwitzerland
- Neuro‐X InstituteÉcole Polytechnique FÉdÉrale de LausanneGenevaSwitzerland
| | - Corrado Sandini
- Developmental Imaging and Psychopathology LaboratoryUniversity of Geneva School of MedicineGenevaSwitzerland
| | - Nada Kojovic
- Autism Brain and Behavior Lab, Faculty of MedicineUniversity of GenevaGenevaSwitzerland
| | - Luigi F. Saccaro
- Faculty of Medicine, Psychiatry DepartmentUniversity of GenevaGenevaSwitzerland
- Psychiatry DepartmentGeneva University HospitalGenevaSwitzerland
| | - Stephan Eliez
- Developmental Imaging and Psychopathology LaboratoryUniversity of Geneva School of MedicineGenevaSwitzerland
- Department of Genetic Medicine and DevelopmentUniversity of Geneva School of MedicineGenevaSwitzerland
| | - Dimitri Van De Ville
- Neuro‐X InstituteÉcole Polytechnique FÉdÉrale de LausanneGenevaSwitzerland
- Department of Radiology and Medical InformaticsUniversity of Geneva (UNIGE)GenevaSwitzerland
| | - Thomas A. W. Bolton
- Neuro‐X InstituteÉcole Polytechnique FÉdÉrale de LausanneGenevaSwitzerland
- Connectomics Laboratory, Department of RadiologyCentre Hospitalier Universitaire Vaudois (CHUV)LausanneSwitzerland
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Wagner MW, Bernhard N, Mndebele G, Vidarsson L, Ertl-Wagner BB. Volumetric differences of thalamic nuclei in children with trisomy 21. Neuroradiol J 2023; 36:581-587. [PMID: 36942548 PMCID: PMC10569191 DOI: 10.1177/19714009231166100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/23/2023] Open
Abstract
OBJECTIVES Histological studies have shown alterations of thalamic nuclei in patients with Down syndrome (DS). The correlation of these changes on MRI (magnetic resonance imaging) is unclear. Therefore, this study investigates volumetric differences of thalamic nuclei in children with DS compared to controls. METHODS Patients were retrospectively identified between 01/2000 and 10/2021. Patient inclusion criteria were: (1) 0-18 years of age, (2) diagnosis of DS, and (3) availability of a brain MRI without parenchymal injury and a non-motion-degraded volumetric T1-weighted sequence. Whole thalamus and thalamic nuclei (n = 25) volumes were analyzed bilaterally relative to the total brain volume (TBV). Two-sided t-tests were used to evaluate differences between groups. Differences were considered significant if the adjusted p-value was <0.05 after correction for multiple hypothesis testing using the Holm-Bonferroni method. RESULTS 21 children with DS (11 females, 52.4%, mean age: 8.6 ± 4.3 years) and 63 age- and sex-matched controls (32 females, 50.8%, 8.6 ± 4.3 years) were studied using automated volumetric segmentation. Significantly smaller ratios were found for nine thalamic nuclei and the whole thalamus on the right and five thalamic nuclei on the left. TBV was significantly smaller in patients with DS (p < 0.001). No significant differences were found between the groups for age and sex. CONCLUSIONS In this exploratory volumetric analysis of the thalamus and thalamic nuclei, we observed statistically significant volumetric changes in children with DS. Our findings confirm prior neuroimaging and histological studies and extend the range of involved thalamic nuclei in pediatric DS.
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Affiliation(s)
- Matthias W Wagner
- Department of Diagnostic Imaging, Division of Neuroradiology, The Hospital for Sick Children, Department of Medical Imaging, University of Toronto, Toronto, Canada
| | - Nirit Bernhard
- The Hospital for Sick Children Department of Paediatrics, University of Toronto, Toronto, Canada
| | - Gopolang Mndebele
- Department of Diagnostic Imaging, Division of Neuroradiology, The Hospital for Sick Children, Department of Medical Imaging, University of Toronto, Toronto, Canada
- Department of Diagnostic Imaging, Nelson Mandela Children’s Hospital, University of the Witwatersrand, Johannesburg, South Africa
| | - Logi Vidarsson
- Department of Diagnostic Imaging, Division of Neuroradiology, The Hospital for Sick Children, Department of Medical Imaging, University of Toronto, Toronto, Canada
| | - Birgit B Ertl-Wagner
- Department of Diagnostic Imaging, Division of Neuroradiology, The Hospital for Sick Children, Department of Medical Imaging, University of Toronto, Toronto, Canada
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Choi EY, Tian L, Su JH, Radovan MT, Tourdias T, Tran TT, Trelle AN, Mormino E, Wagner AD, Rutt BK. Thalamic nuclei atrophy at high and heterogenous rates during cognitively unimpaired human aging. Neuroimage 2022; 262:119584. [PMID: 36007822 PMCID: PMC9787236 DOI: 10.1016/j.neuroimage.2022.119584] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2022] [Revised: 08/09/2022] [Accepted: 08/21/2022] [Indexed: 02/02/2023] Open
Abstract
The thalamus is a central integration structure in the brain, receiving and distributing information among the cerebral cortex, subcortical structures, and the peripheral nervous system. Prior studies clearly show that the thalamus atrophies in cognitively unimpaired aging. However, the thalamus is comprised of multiple nuclei involved in a wide range of functions, and the age-related atrophy of individual thalamic nuclei remains unknown. Using a recently developed automated method of identifying thalamic nuclei (3T or 7T MRI with white-matter-nulled MPRAGE contrast and THOMAS segmentation) and a cross-sectional design, we evaluated the age-related atrophy rate for 10 thalamic nuclei (AV, CM, VA, VLA, VLP, VPL, pulvinar, LGN, MGN, MD) and an epithalamic nucleus (habenula). We also used T1-weighted images with the FreeSurfer SAMSEG segmentation method to identify and measure age-related atrophy for 11 extra-thalamic structures (cerebral cortex, cerebral white matter, cerebellar cortex, cerebellar white matter, amygdala, hippocampus, caudate, putamen, nucleus accumbens, pallidum, and lateral ventricle). In 198 cognitively unimpaired participants with ages spanning 20-88 years, we found that the whole thalamus atrophied at a rate of 0.45% per year, and that thalamic nuclei had widely varying age-related atrophy rates, ranging from 0.06% to 1.18% per year. A functional grouping analysis revealed that the thalamic nuclei involved in cognitive (AV, MD; 0.53% atrophy per year), visual (LGN, pulvinar; 0.62% atrophy per year), and auditory/vestibular (MGN; 0.64% atrophy per year) functions atrophied at significantly higher rates than those involved in motor (VA, VLA, VLP, and CM; 0.37% atrophy per year) and somatosensory (VPL; 0.32% atrophy per year) functions. A proximity-to-CSF analysis showed that the group of thalamic nuclei situated immediately adjacent to CSF atrophied at a significantly greater atrophy rate (0.59% atrophy per year) than that of the group of nuclei located farther from CSF (0.36% atrophy per year), supporting a growing hypothesis that CSF-mediated factors contribute to neurodegeneration. We did not find any significant hemispheric differences in these rates of change for thalamic nuclei. Only the CM thalamic nucleus showed a sex-specific difference in atrophy rates, atrophying at a greater rate in male versus female participants. Roughly half of the thalamic nuclei showed greater atrophy than all extra-thalamic structures examined (0% to 0.54% per year). These results show the value of white-matter-nulled MPRAGE imaging and THOMAS segmentation for measuring distinct thalamic nuclei and for characterizing the high and heterogeneous atrophy rates of the thalamus and its nuclei across the adult lifespan. Collectively, these methods and results advance our understanding of the role of thalamic substructures in neurocognitive and disease-related changes that occur with aging.
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Affiliation(s)
- Eun Young Choi
- Department of Neurosurgery, Stanford University, 300 Pasteur Drive, MC5327, Stanford, CA 94305, USA
| | - Lu Tian
- Department of Biomedical Data Science, 1265 Welch Road, MC5464, Stanford, CA 94305, USA
| | - Jason H. Su
- Department of Radiology, Stanford University, 300 Pasteur Drive, MC5488, Stanford, CA 94305, USA,Department of Electrical Engineering, Stanford University, 350 Jane Stanford Way, MC9505, Stanford, CA 94305, USA
| | - Matthew T. Radovan
- Department of Computer Science, Stanford University, 353 Jane Stanford Way, MC9025, Stanford, CA 94305, USA
| | - Thomas Tourdias
- Department of Neuroradiology, Bordeaux University Hospital, Bordeaux, France,INSERM U1215, Neurocentre Magendie, University of Bordeaux, France
| | - Tammy T. Tran
- Department of Psychology, Stanford University, Building 420, MC2130, Stanford, CA 94305, USA
| | - Alexandra N. Trelle
- Department of Psychology, Stanford University, Building 420, MC2130, Stanford, CA 94305, USA
| | - Elizabeth Mormino
- Department of Neurology and Neurological Sciences, Stanford, University, 300 Pasteur Drive, MC5235, Stanford, CA 94305, USA,Wu Tsai Neurosciences Institute, Stanford University, 290 Jane Stanford Way, Stanford, CA 94305, USA
| | - Anthony D. Wagner
- Department of Psychology, Stanford University, Building 420, MC2130, Stanford, CA 94305, USA,Wu Tsai Neurosciences Institute, Stanford University, 290 Jane Stanford Way, Stanford, CA 94305, USA
| | - Brian K. Rutt
- Department of Radiology, Stanford University, 300 Pasteur Drive, MC5488, Stanford, CA 94305, USA,Wu Tsai Neurosciences Institute, Stanford University, 290 Jane Stanford Way, Stanford, CA 94305, USA,Corresponding author. (B.K. Rutt)
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Spatial-temporal topography in neurogenesis of the macaque thalamus. Brain Struct Funct 2022; 227:1673-1682. [PMID: 35147755 DOI: 10.1007/s00429-022-02463-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Accepted: 01/23/2022] [Indexed: 11/02/2022]
Abstract
Maternal injection of 3H-thymidine ([3H]dT) during gestation in non-human primates (NHPs) has been used to determine the time of neurogenesis for various brain areas, including the lateral geniculate (LGN) and the pulvinar (PUL) nuclei of the caudal thalamus. Here, we examine neurogenesis in the rostral thalamus, with focus on the mediodorsal (MD) and the anterior nuclei (ANT), to determine if neurogenesis of rostral and caudal thalamic nuclei is concurrent or instead temporally staggered. The MacBrainResource (MBR) search function identified archived cases (N = 10) of [3H]dT labeled specimens, with injection dates ranging from embryonic day 25 (E25)-E50 and postnatal sacrifice dates. Slides were scanned to create digital images for subsequent analysis using Stereo Investigator software. Labeled neurons were mapped within a contour that encompassed the entire rostral thalamus. These maps were superimposed onto closely corresponding sections from the online BrainMaps macaque atlas to facilitate analysis. Our novel approach uncovered a previously undetected spatial-temporal patterning of neurogenesis in the thalamus. At E30, labeled neurons were located in a compact medial band; at E38-E40, labeling was dense ventrolaterally, and at E43, labeling predominated laterally at rostral levels and was widely distributed at caudal levels. Peak neurogenesis occurs earlier in MD (E30-E43) and ANT (E31-E43) than in LGN (E36-E43) and PUL (E36-E45). Birth-dating of neurons in MD and ANT, two higher order relay nuclei implicated in the pathology of schizophrenia, provides further insight into the critical period of vulnerability during which early developmental perturbation may increase incidence of schizophrenia later in life.
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Thalamic subnetworks as units of function. Nat Neurosci 2022; 25:140-153. [DOI: 10.1038/s41593-021-00996-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2020] [Accepted: 12/07/2021] [Indexed: 01/15/2023]
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Förster A, Model V, Gos T, Frodl T, Schiltz K, Dobrowolny H, Meyer-Lotz G, Guest PC, Mawrin C, Bernstein HG, Bogerts B, Schlaaff K, Steiner J. Reduced GABAergic neuropil and interneuron profiles in schizophrenia: Complementary analysis of disease course-related differences. J Psychiatr Res 2021; 145:50-59. [PMID: 34864489 DOI: 10.1016/j.jpsychires.2021.11.028] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Revised: 10/12/2021] [Accepted: 11/17/2021] [Indexed: 11/21/2022]
Abstract
BACKGROUND GABAergic interneuron dysfunction has been implicated in the pathophysiology of schizophrenia. Expression of glutamic acid decarboxylase (GAD), a key enzyme in GABA synthesis, may also be altered. Here, we have simultaneously evaluated GAD-immunoreactive (GAD-ir) neuropil and cell profiles in schizophrenia-relevant brain regions, and analysed disease-course related differences. METHODS GAD65/67 immunoreactivity was quantified in specific brain regions for profiles of fibres and cell bodies of interneurons by automated digital image analysis in post-mortem brains of 16 schizophrenia patients from paranoid (n = 10) and residual (n = 6) diagnostic subgroups and 16 matched controls. Regions of interest were superior temporal gyrus (STG) layers III and V, mediodorsal (MD) and laterodorsal (LD) thalamus, and hippocampal CA1 and dentate gyrus (DG) regions. RESULTS A reduction in GAD-ir neuropil profiles (p < 0.001), particularly in STG layer V (p = 0.012) and MD (p = 0.001), paralleled decreased GAD-ir cell profiles (p = 0.029) in schizophrenia patients compared to controls. Paranoid schizophrenia patients had lower GAD-ir neuron cell profiles in STG layers III (p = 0.007) and V (p = 0.001), MD (p = 0.002), CA1 (p = 0.001) and DG (p = 0.043) than residual patients. There was no difference in GAD-ir neuropil profiles between paranoid and residual subgroups (p = 0.369). CONCLUSIONS These results support the hypothesis of GABAergic dysfunction in schizophrenia. They show a more prominent reduction of GAD-ir interneurons in paranoid versus residual patients, suggestive of more pronounced GABAergic dysfunction in the former. Fully automated analyses of histological sections represent a step towards user-independent assessment of brain structure.
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Affiliation(s)
- Antonia Förster
- Department of Psychiatry, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany; Laboratory of Translational Psychiatry, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany; German Center for Mental Health (DZP), Center for Intervention and Research on Adaptive and Maladaptive Brain Circuits Underlying Mental Health (C-I-R-C), Jena-Magdeburg-Halle, Germany
| | - Vera Model
- Department of Psychiatry, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany; Laboratory of Translational Psychiatry, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany; German Center for Mental Health (DZP), Center for Intervention and Research on Adaptive and Maladaptive Brain Circuits Underlying Mental Health (C-I-R-C), Jena-Magdeburg-Halle, Germany
| | - Tomasz Gos
- Department of Psychiatry, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany; Laboratory of Translational Psychiatry, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany; Department of Forensic Medicine, Medical University of Gdańsk, Gdańsk, Poland
| | - Thomas Frodl
- Department of Psychiatry, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany; German Center for Mental Health (DZP), Center for Intervention and Research on Adaptive and Maladaptive Brain Circuits Underlying Mental Health (C-I-R-C), Jena-Magdeburg-Halle, Germany; Center for Behavioral Brain Sciences, Magdeburg, Germany
| | - Kolja Schiltz
- Department of Psychiatry, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany; Laboratory of Translational Psychiatry, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany; Center for Behavioral Brain Sciences, Magdeburg, Germany; Department of Forensic Psychiatry, Mental Hospital, Ludwig-Maximilians-University, Munich, Germany
| | - Henrik Dobrowolny
- Department of Psychiatry, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany; Laboratory of Translational Psychiatry, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany; German Center for Mental Health (DZP), Center for Intervention and Research on Adaptive and Maladaptive Brain Circuits Underlying Mental Health (C-I-R-C), Jena-Magdeburg-Halle, Germany
| | - Gabriela Meyer-Lotz
- Department of Psychiatry, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany; Laboratory of Translational Psychiatry, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany; German Center for Mental Health (DZP), Center for Intervention and Research on Adaptive and Maladaptive Brain Circuits Underlying Mental Health (C-I-R-C), Jena-Magdeburg-Halle, Germany
| | - Paul C Guest
- Laboratory of Neuroproteomics, Department of Biochemistry and Tissue Biology, University of Campinas (UNICAMP), Campinas, Brazil
| | - Christian Mawrin
- Center for Behavioral Brain Sciences, Magdeburg, Germany; Department of Neuropathology, University of Magdeburg, Magdeburg, Germany
| | - Hans-Gert Bernstein
- Department of Psychiatry, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany; Laboratory of Translational Psychiatry, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany
| | - Bernhard Bogerts
- Department of Psychiatry, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany; Laboratory of Translational Psychiatry, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany; Center for Behavioral Brain Sciences, Magdeburg, Germany; Salus Institute, Magdeburg, Germany
| | - Konstantin Schlaaff
- Department of Psychiatry, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany; Laboratory of Translational Psychiatry, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany; German Center for Mental Health (DZP), Center for Intervention and Research on Adaptive and Maladaptive Brain Circuits Underlying Mental Health (C-I-R-C), Jena-Magdeburg-Halle, Germany
| | - Johann Steiner
- Department of Psychiatry, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany; Laboratory of Translational Psychiatry, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany; German Center for Mental Health (DZP), Center for Intervention and Research on Adaptive and Maladaptive Brain Circuits Underlying Mental Health (C-I-R-C), Jena-Magdeburg-Halle, Germany; Center for Behavioral Brain Sciences, Magdeburg, Germany.
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Vigen TR, Brudek T, Pakkenberg B, Olesen MV. Quantitative Cellular Changes in the Thalamus of Patients with Multiple System Atrophy. Neuroscience 2021; 459:142-152. [PMID: 33577952 DOI: 10.1016/j.neuroscience.2021.02.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 01/29/2021] [Accepted: 02/02/2021] [Indexed: 01/10/2023]
Abstract
The thalamus is a brain region consisting of anatomical and functional connections between various spinal, subcortical, and cortical regions, which has a putative role in the clinical manifestation of Multiple System Atrophy (MSA). Previous stereological studies have reported significant anatomical alterations in diverse brain regions of MSA patients, including the cerebral cortex, basal ganglia and white matter, but no quantitative studies have examined the thalamus. To establish the extent of thalamic involvement, we applied stereological methods to estimate the total number of neurons and glial cells (oligodendrocytes, astrocytes and microglia) as well as the volume in two thalamic sub-regions, the mediodorsal nucleus (MDT) and the anterior principal nucleus (APn), in brains from ten MSA patients and 11 healthy control subjects. Compared to healthy controls, MSA patients had significantly fewer neurons (26%) in the MDT, but not the APn. We also found significantly more astrocytes (32%) and microglia (54%) in the MDT, with no such changes in the APn. Finally, we saw no group differences in the total number of oligodendrocytes. Our findings show a region-specific loss of thalamic neurons that occurs without loss of oligodendrocytes, whereas thalamic microgliosis seems to occur alongside astrogliosis. These pathological changes in the thalamus may contribute to the cognitive impairment seen in most patients with MSA.
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Affiliation(s)
- Tanya R Vigen
- Research Laboratory for Stereology and Neuroscience, Copenhagen University Hospital, Bispebjerg and Frederiksberg Hospital, Denmark
| | - Tomasz Brudek
- Research Laboratory for Stereology and Neuroscience, Copenhagen University Hospital, Bispebjerg and Frederiksberg Hospital, Denmark
| | - Bente Pakkenberg
- Research Laboratory for Stereology and Neuroscience, Copenhagen University Hospital, Bispebjerg and Frederiksberg Hospital, Denmark; Institute of Clinical Medicine, Faculty of Health and Medical Sciences, University of Copenhagen, DK-2200 Copenhagen, Denmark.
| | - Mikkel V Olesen
- Research Laboratory for Stereology and Neuroscience, Copenhagen University Hospital, Bispebjerg and Frederiksberg Hospital, Denmark
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Liu D, Zhao C, Wang W, Wang Y, Li R, Sun J, Liu J, Liu M, Zhang X, Liang Y, Li H. Altered Gray Matter Volume and Functional Connectivity in Human Immunodeficiency Virus-Infected Adults. Front Neurosci 2020; 14:601063. [PMID: 33343289 PMCID: PMC7744568 DOI: 10.3389/fnins.2020.601063] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Accepted: 11/05/2020] [Indexed: 01/10/2023] Open
Abstract
People living with human immunodeficiency virus (HIV) (PLWH) are at high risk of neurocognitive impairment. The pathogenesis of neurocognitive impairment remains unclear, and there is still no diagnostic biomarker. By coupling three-dimensional T1-weighted imaging and resting-state functional imaging, we explored structural and functional alterations in PLWH and examined whether such imaging alterations had the potential to denote neurocognitive function. A total of 98 PLWH and 47 seronegative controls aged 20–53 years were recruited. Structural alterations were first explored between HIV-negative controls and PLWH. Subsequently, brain regions showing gray matter alterations were used as seeds for separate whole-brain functional connectivity (FC) analysis. Finally, the relationships between imaging alterations and cognitive function were explored. PLWH suffered from thalamus, occipital lobe, and hippocampus/parahippocampus atrophy. Visual cortices in PLWH showed decreased anticorrelation with the posterior cingulate cortex and left angular gyrus of the default mode network. FC within the visual cortices (between the left calcarine and right calcarine) and in the thalamic prefrontal circuit and between the thalamus and somatosensory association cortex were also altered. In addition, FC between the left thalamus and right dorsolateral prefrontal cortex in the cognitively impaired group was significantly different from that in the cognitively normal group in PLWH. Partial correlation analysis uncorrected for multiple comparisons suggested that some imaging alterations can be associated with neurocognition. Our study supports the presence of brain atrophy and functional reconfiguration in PLWH. Imaging alterations can be associated with neurocognitive function. We hold that neuroimaging is a promising approach in evaluating PLWH and might have the potential to clarify the pathogenesis of HIV-associated neurocognitive disorder.
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Affiliation(s)
- Dan Liu
- Department of Radiology, Beijing Youan Hospital, Capital Medical University, Beijing, China
| | - Cui Zhao
- School of Biomedical Engineering, Capital Medical University, Beijing, China
| | - Wei Wang
- Department of Radiology, Beijing Youan Hospital, Capital Medical University, Beijing, China
| | - Yuanyuan Wang
- Department of Radiology, Beijing Second Hospital, Beijing, China
| | - Ruili Li
- Department of Radiology, Beijing Youan Hospital, Capital Medical University, Beijing, China
| | - Jun Sun
- Department of Radiology, Beijing Youan Hospital, Capital Medical University, Beijing, China
| | - Jiaojiao Liu
- Department of Radiology, Beijing Youan Hospital, Capital Medical University, Beijing, China
| | - Mingming Liu
- Physical Examination Center, Cangzhou Central Hospital, Hebei, China
| | - Xu Zhang
- School of Biomedical Engineering, Capital Medical University, Beijing, China
| | - Ying Liang
- School of Biomedical Engineering, Capital Medical University, Beijing, China
| | - Hongjun Li
- Department of Radiology, Beijing Youan Hospital, Capital Medical University, Beijing, China.,Beijing University of Aeronautics and Astronautics, Beijing, China
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Steullet P. Thalamus-related anomalies as candidate mechanism-based biomarkers for psychosis. Schizophr Res 2020; 226:147-157. [PMID: 31147286 DOI: 10.1016/j.schres.2019.05.027] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Revised: 05/15/2019] [Accepted: 05/17/2019] [Indexed: 02/08/2023]
Abstract
Identification of reliable biomarkers of prognosis in subjects with high risk to psychosis is an essential step to improve care and treatment of this population of help-seekers. Longitudinal studies highlight some clinical criteria, cognitive deficits, patterns of gray matter alterations and profiles of blood metabolites that provide some levels of prediction regarding the conversion to psychosis. Further effort is warranted to validate these results and implement these types of approaches in clinical settings. Such biomarkers may however fall short in entangling the biological mechanisms underlying the disease progression, an essential step in the development of novel therapies. Circuit-based approaches, which map on well-identified cerebral functions, could meet these needs. Converging evidence indicates that thalamus abnormalities are central to schizophrenia pathophysiology, contributing to clinical symptoms, cognitive and sensory deficits. This review highlights the various thalamus-related anomalies reported in individuals with genetic risks and in the different phases of the disorder, from prodromal to chronic stages. Several anomalies are potent endophenotypes, while others exist in clinical high-risk subjects and worsen in those who convert to full psychosis. Aberrant functional coupling between thalamus and cortex, low glutamate content and readouts from resting EEG carry predictive values for transition to psychosis or functional outcome. In this context, thalamus-related anomalies represent a valuable entry point to tackle circuit-based alterations associated with the emergence of psychosis. This review also proposes that longitudinal surveys of neuroimaging, EEG readouts associated with circuits encompassing the mediodorsal, pulvinar in high-risk individuals could unveil biological mechanisms contributing to this psychiatric disorder.
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Affiliation(s)
- Pascal Steullet
- Center of Psychiatric Neuroscience, Department of Psychiatry, Centre Hospitalier Universitaire Vaudois, Site de Cery, 1008 Prilly-Lausanne, Switzerland.
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10
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Geier KT, Buchsbaum BR, Parimoo S, Olsen RK. The role of anterior and medial dorsal thalamus in associative memory encoding and retrieval. Neuropsychologia 2020; 148:107623. [DOI: 10.1016/j.neuropsychologia.2020.107623] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2019] [Revised: 09/04/2020] [Accepted: 09/06/2020] [Indexed: 02/06/2023]
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11
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Selemon LD, Begovic A. Reduced Midbrain Dopamine Neuron Number in the Adult Non-human Primate Brain after Fetal Radiation Exposure. Neuroscience 2020; 442:193-201. [PMID: 32659340 DOI: 10.1016/j.neuroscience.2020.07.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Revised: 06/17/2020] [Accepted: 07/02/2020] [Indexed: 11/19/2022]
Abstract
Early gestation is a neurodevelopmental period that is especially vulnerable to environmental insult and one in which neurogenesis features prominently. Prenatal perturbation during early gestation has been linked to neuropsychiatric illnesses such as autism and schizophrenia, and severe environmental insult during this period can result in profound mental impairment. Midbrain dopamine neurons are generated during early gestation and play a key role in the motor, cognitive and reward circuitries implicated in neuropsychiatric disease and addiction. This study examined the impact of curtailing neurogenesis in early gestation on neuron number in the midbrain dopamine group, i.e., the substantia nigra and contiguous ventral tegmental area. Rhesus macaque monkeys were exposed in utero on embryonic days 39-41 to x-irradiation (3-4 exposures of 50 cGy over 3-7 days totalling <200 cGy) and allowed to mature to full adulthood. Stereologic cell counts of tyrosine hydroxylase-positive neurons in the midbrain dopamine group were performed in adult monkeys, as were measurements of somal size. Mean total neuron number in the irradiated monkeys was significantly reduced on average by 33% compared to that of the control group. Somal size did not differ between the groups, suggesting that the integrity of survivor populations was not impacted. Reduced midbrain dopamine neuron number in fetally irradiated, adult monkeys indicates that radiation exposure during the critical period of neurogenesis results in an enduring reduction of this population and underscores the susceptibility of early neurodevelopmental processes to irreversible damage from environmental exposures.
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Affiliation(s)
- Lynn D Selemon
- Department of Neuroscience, Yale University School of Medicine, New Haven, CT, United States.
| | - Anita Begovic
- Department of Neuroscience, Yale University School of Medicine, New Haven, CT, United States
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12
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Lee J, Choi JH, Rah JC. Frequency-dependent gating of feedforward inhibition in thalamofrontal synapses. Mol Brain 2020; 13:68. [PMID: 32375833 PMCID: PMC7201790 DOI: 10.1186/s13041-020-00608-2] [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: 02/23/2020] [Accepted: 04/22/2020] [Indexed: 11/10/2022] Open
Abstract
Thalamic recruitment of feedforward inhibition is known to enhance the fidelity of the receptive field by limiting the temporal window during which cortical neurons integrate excitatory inputs. Feedforward inhibition driven by the mediodorsal nucleus of the thalamus (MD) has been previously observed, but its physiological function and regulation remain unknown. Accumulating evidence suggests that elevated neuronal activity in the prefrontal cortex is required for the short-term storage of information. Furthermore, the elevated neuronal activity is supported by the reciprocal connectivity between the MD and the medial prefrontal cortex (mPFC). Therefore, detailed knowledge about the synaptic connections during high-frequency activity is critical for understanding the mechanism of short-term memory. In this study, we examined how feedforward inhibition of thalamofrontal connectivity is modulated by activity frequency. We observed greater short-term synaptic depression during disynaptic inhibition than in thalamic excitatory synapses during high-frequency activities. The strength of feedforward inhibition became weaker as the stimulation continued, which, in turn, enhanced the range of firing jitter in a frequency-dependent manner. We postulated that this phenomenon was primarily due to the increased failure rate of evoking action potentials in parvalbumin-expressing inhibitory neurons. These findings suggest that the MD-mPFC pathway is dynamically regulated by an excitatory-inhibitory balance in an activity-dependent manner. During low-frequency activities, excessive excitations are inhibited, and firing is restricted to a limited temporal range by the strong feedforward inhibition. However, during high-frequency activities, such as during short-term memory, the activity can be transferred in a broader temporal range due to the decreased feedforward inhibition.
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Affiliation(s)
- Jungmin Lee
- Korea Brain Research Institute, 61 Cheomdan-ro, Daegu, 41062, Republic of Korea.,Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science & Technology, Daegu, 42988, Republic of Korea
| | - Joon Ho Choi
- Korea Brain Research Institute, 61 Cheomdan-ro, Daegu, 41062, Republic of Korea
| | - Jong-Cheol Rah
- Korea Brain Research Institute, 61 Cheomdan-ro, Daegu, 41062, Republic of Korea. .,Department of Brain and Cognitive Sciences, Daegu Gyeongbuk Institute of Science & Technology, Daegu, 42988, Republic of Korea.
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Multiple Adenosine-Dopamine (A2A-D2 Like) Heteroreceptor Complexes in the Brain and Their Role in Schizophrenia. Cells 2020; 9:cells9051077. [PMID: 32349279 PMCID: PMC7290895 DOI: 10.3390/cells9051077] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2020] [Revised: 04/20/2020] [Accepted: 04/20/2020] [Indexed: 12/21/2022] Open
Abstract
In the 1980s and 1990s, the concept was introduced that molecular integration in the Central Nervous System could develop through allosteric receptor–receptor interactions in heteroreceptor complexes presents in neurons. A number of adenosine–dopamine heteroreceptor complexes were identified that lead to the A2A-D2 heteromer hypothesis of schizophrenia. The hypothesis is based on strong antagonistic A2A-D2 receptor–receptor interactions and their presence in the ventral striato-pallidal GABA anti-reward neurons leading to reduction of positive symptoms. Other types of adenosine A2A heteroreceptor complexes are also discussed in relation to this disease, such as A2A-D3 and A2A-D4 heteroreceptor complexes as well as higher order A2A-D2-mGluR5 and A2A-D2-Sigma1R heteroreceptor complexes. The A2A receptor protomer can likely modulate the function of the D4 receptors of relevance for understanding cognitive dysfunction in schizophrenia. A2A-D2-mGluR5 complex is of interest since upon A2A/mGluR5 coactivation they appear to synergize in producing strong inhibition of the D2 receptor protomer. For understanding the future of the schizophrenia treatment, the vulnerability of the current A2A-D2like receptor complexes will be tested in animal models of schizophrenia. A2A-D2-Simag1R complexes hold the highest promise through Sigma1R enhancement of inhibition of D2R function. In line with this work, Lara proposed a highly relevant role of adenosine for neurobiology of schizophrenia.
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Differential Roles of Mediodorsal Nucleus of the Thalamus and Prefrontal Cortex in Decision-Making and State Representation in a Cognitive Control Task Measuring Deficits in Schizophrenia. J Neurosci 2020; 40:1650-1667. [PMID: 31941665 DOI: 10.1523/jneurosci.1703-19.2020] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Revised: 12/12/2019] [Accepted: 01/05/2020] [Indexed: 11/21/2022] Open
Abstract
The mediodorsal nucleus of the thalamus (MD) is reciprocally connected with the prefrontal cortex (PFC), and although the MD has been implicated in a range of PFC-dependent cognitive functions (Watanabe and Funahashi, 2012; Mitchell and Chakraborty, 2013; Parnaudeau et al., 2018), little is known about how MD neurons in the primate participate specifically in cognitive control, a capability that reflects the ability to use contextual information (such as a rule) to modify responses to environmental stimuli. To learn how the MD-PFC thalamocortical network is engaged to mediate forms of cognitive control that are selectively disrupted in schizophrenia, we trained male monkeys to perform a variant of the AX continuous performance task, which reliably measures cognitive control deficits in patients (Henderson et al., 2012) and used linear multielectrode arrays to record neural activity in the MD and PFC simultaneously. We found that the two structures made clearly different contributions to distributed processing for cognitive control: MD neurons were specialized for decision-making and response selection, whereas prefrontal neurons were specialized to preferentially encode the environmental state on which the decision was based. In addition, we observed that functional coupling between MD and PFC was strongest when the decision as to which of the two responses in the task to execute was being made. These findings delineate unique contributions of MD and PFC to distributed processing for cognitive control and characterized neural dynamics in this network associated with normative cognitive control performance.SIGNIFICANCE STATEMENT Cognitive control is fundamental to healthy human executive functioning (Miller and Cohen, 2001) and deficits in patients with schizophrenia relate to decreased functional activation of the MD thalamus and the prefrontal cortex (Minzenberg et al., 2009), which are reciprocally linked (Goldman-Rakic and Porrino, 1985; Xiao et al., 2009). We carry out simultaneous neural recordings in the MD and PFC while monkeys perform a cognitive control task translated from patients with schizophrenia to relate thalamocortical dynamics to cognitive control performance. Our data suggest that state representation and decision-making computations for cognitive control are preferentially performed by PFC and MD, respectively. This suggests experiments to parse decision-making and state representation deficits in patients while providing novel computational targets for future therapies.
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15
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Dehghani N, Wimmer RD. A Computational Perspective of the Role of the Thalamus in Cognition. Neural Comput 2019; 31:1380-1418. [PMID: 31113299 DOI: 10.1162/neco_a_01197] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The thalamus has traditionally been considered as only a relay source of cortical inputs, with hierarchically organized cortical circuits serially transforming thalamic signals to cognitively relevant representations. Given the absence of local excitatory connections within the thalamus, the notion of thalamic relay seemed like a reasonable description over the past several decades. Recent advances in experimental approaches and theory provide a broader perspective on the role of the thalamus in cognitively relevant cortical computations and suggest that only a subset of thalamic circuit motifs fits the relay description. Here, we discuss this perspective and highlight the potential role for the thalamus, and specifically the mediodorsal (MD) nucleus, in the dynamic selection of cortical representations through a combination of intrinsic thalamic computations and output signals that change cortical network functional parameters. We suggest that through the contextual modulation of cortical computation, the thalamus and cortex jointly optimize the information and cost trade-off in an emergent fashion. We emphasize that coordinated experimental and theoretical efforts will provide a path to understanding the role of the thalamus in cognition, along with an understanding to augment cognitive capacity in health and disease.
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Affiliation(s)
- Nima Dehghani
- Department of Physics and Center for Brains, Minds and Machines (CBMM), MIT, Cambridge, MA 02139, U.S.A.
| | - Ralf D Wimmer
- Department of Brain and Cognitive Sciences, MIT, Cambridge, MA 02139, U.S.A.
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16
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Abnormal Effective Connectivity of the Anterior Forebrain Regions in Disorders of Consciousness. Neurosci Bull 2018; 34:647-658. [PMID: 29959668 DOI: 10.1007/s12264-018-0250-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2018] [Accepted: 04/25/2018] [Indexed: 01/21/2023] Open
Abstract
A number of studies have indicated that disorders of consciousness result from multifocal injuries as well as from the impaired functional and anatomical connectivity between various anterior forebrain regions. However, the specific causal mechanism linking these regions remains unclear. In this study, we used spectral dynamic causal modeling to assess how the effective connections (ECs) between various regions differ between individuals. Next, we used connectome-based predictive modeling to evaluate the performance of the ECs in predicting the clinical scores of DOC patients. We found increased ECs from the striatum to the globus pallidus as well as from the globus pallidus to the posterior cingulate cortex, and decreased ECs from the globus pallidus to the thalamus and from the medial prefrontal cortex to the striatum in DOC patients as compared to healthy controls. Prediction of the patients' outcome was effective using the negative ECs as features. In summary, the present study highlights a key role of the thalamo-basal ganglia-cortical loop in DOCs and supports the anterior forebrain mesocircuit hypothesis. Furthermore, EC could be potentially used to assess the consciousness level.
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17
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Penner J, Osuch EA, Schaefer B, Théberge J, Neufeld RWJ, Menon RS, Rajakumar N, Bourne JA, Williamson PC. Higher order thalamic nuclei resting network connectivity in early schizophrenia and major depressive disorder. Psychiatry Res Neuroimaging 2018; 272:7-16. [PMID: 29247717 DOI: 10.1016/j.pscychresns.2017.12.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/13/2017] [Revised: 12/05/2017] [Accepted: 12/06/2017] [Indexed: 12/21/2022]
Abstract
The pulvinar and the mediodorsal (MDN) nuclei of the thalamus are higher order nuclei which have been implicated in directed effort and corollary discharge systems. We used seed-based resting fMRI to examine functional connectivity to bilateral pulvinar and MDN in 24 schizophrenic patients (SZ), 24 major depressive disorder patients (MDD), and 24 age-matched healthy controls. SZ had less connectivity than controls between the left pulvinar and precuneus, left ventral-lateral prefrontal cortex (vlPFC), and superior and medial-frontal regions, between the right pulvinar and right frontal pole, and greater connectivity between the right MDN and left dorsolateral prefrontal cortex (dlPFC). SZ had less connectivity than MDD between the left pulvinar and ventral anterior cingulate (vACC), left vlPFC, anterior insula, posterior cingulate cortex (PCC), and right hippocampus, between the right pulvinar and right PCC, and between the right MDN and right dorsal anterior cingulate (dACC). This is the first study to measure the functional connectivity to the higher order nuclei of the thalamus in both SZ and MDD. We observed less connectivity in SZ than MDD between pulvinar and emotional encoding regions, a directed effort region, and a region involved in representation and salience, and between MDN and a directed effort region.
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Affiliation(s)
- Jacob Penner
- Department of Psychiatry, University of Western Ontario, London, Ontario, Canada; Imaging Division, Lawson Health Research Institute, London, Ontario, Canada; First Episode Mood & Anxiety Program (FEMAP), London Health Sciences Centre, London, Ontario, Canada.
| | - Elizabeth A Osuch
- Department of Psychiatry, University of Western Ontario, London, Ontario, Canada; Department of Medical Biophysics, University of Western Ontario, London, Ontario, Canada; First Episode Mood & Anxiety Program (FEMAP), London Health Sciences Centre, London, Ontario, Canada
| | - Betsy Schaefer
- Department of Psychiatry, University of Western Ontario, London, Ontario, Canada
| | - Jean Théberge
- Department of Psychiatry, University of Western Ontario, London, Ontario, Canada; Department of Medical Biophysics, University of Western Ontario, London, Ontario, Canada; Imaging Division, Lawson Health Research Institute, London, Ontario, Canada
| | - Richard W J Neufeld
- Department of Psychiatry, University of Western Ontario, London, Ontario, Canada; Department of Psychology, University of Western Ontario, London, Ontario, Canada; Department of Neuroscience Program, University of Western Ontario, London, Ontario, Canada
| | - Ravi S Menon
- Department of Medical Biophysics, University of Western Ontario, London, Ontario, Canada; Centre for Functional and Metabolic Mapping, Robarts Research Institute, London, Ontario, Canada; Imaging Division, Lawson Health Research Institute, London, Ontario, Canada
| | - Nagalingam Rajakumar
- Department of Psychiatry, University of Western Ontario, London, Ontario, Canada; Department of Anatomy and Cell Biology, University of Western Ontario, London, Ontario, Canada
| | - James A Bourne
- Australian Regenerative Medicine Institute, Monash University, Clayton, Australia
| | - Peter C Williamson
- Department of Psychiatry, University of Western Ontario, London, Ontario, Canada; Department of Medical Biophysics, University of Western Ontario, London, Ontario, Canada; Imaging Division, Lawson Health Research Institute, London, Ontario, Canada
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18
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Ouhaz Z, Fleming H, Mitchell AS. Cognitive Functions and Neurodevelopmental Disorders Involving the Prefrontal Cortex and Mediodorsal Thalamus. Front Neurosci 2018; 12:33. [PMID: 29467603 PMCID: PMC5808198 DOI: 10.3389/fnins.2018.00033] [Citation(s) in RCA: 88] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2017] [Accepted: 01/15/2018] [Indexed: 11/13/2022] Open
Abstract
The mediodorsal nucleus of the thalamus (MD) has been implicated in executive functions (such as planning, cognitive control, working memory, and decision-making) because of its significant interconnectivity with the prefrontal cortex (PFC). Yet, whilst the roles of the PFC have been extensively studied, how the MD contributes to these cognitive functions remains relatively unclear. Recently, causal evidence in monkeys has demonstrated that in everyday tasks involving rapid updating (e.g., while learning something new, making decisions, or planning the next move), the MD and frontal cortex are working in close partnership. Furthermore, researchers studying the MD in rodents have been able to probe the underlying mechanisms of this relationship to give greater insights into how the frontal cortex and MD might interact during the performance of these essential tasks. This review summarizes the circuitry and known neuromodulators of the MD, and considers the most recent behavioral, cognitive, and neurophysiological studies conducted in monkeys and rodents; in total, this evidence demonstrates that MD makes a critical contribution to cognitive functions. We propose that communication occurs between the MD and the frontal cortex in an ongoing, fluid manner during rapid cognitive operations, via the means of efference copies of messages passed through transthalamic routes; the conductance of these messages may be modulated by other brain structures interconnected to the MD. This is similar to the way in which other thalamic structures have been suggested to carry out forward modeling associated with rapid motor responding and visual processing. Given this, and the marked thalamic pathophysiology now identified in many neuropsychiatric disorders, we suggest that changes in the different subdivisions of the MD and their interconnections with the cortex could plausibly give rise to a number of the otherwise disparate symptoms (including changes to olfaction and cognitive functioning) that are associated with many different neuropsychiatric disorders. In particular, we will focus here on the cognitive symptoms of schizophrenia and suggest testable hypotheses about how changes to MD-frontal cortex interactions may affect cognitive processes in this disorder.
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Affiliation(s)
- Zakaria Ouhaz
- Department of Experimental Psychology, University of Oxford, Oxford, United Kingdom
| | - Hugo Fleming
- Department of Experimental Psychology, University of Oxford, Oxford, United Kingdom
| | - Anna S Mitchell
- Department of Experimental Psychology, University of Oxford, Oxford, United Kingdom
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19
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Determining the Neural Substrate for Encoding a Memory of Human Pain and the Influence of Anxiety. J Neurosci 2017; 37:11806-11817. [PMID: 29097595 PMCID: PMC5719969 DOI: 10.1523/jneurosci.0750-17.2017] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2017] [Revised: 08/31/2017] [Accepted: 09/05/2017] [Indexed: 12/02/2022] Open
Abstract
To convert a painful stimulus into a briefly maintainable construct when the painful stimulus is no longer accessible is essential to guide human behavior and avoid dangerous situations. Because of the aversive nature of pain, this encoding process might be influenced by emotional aspects and could thus vary across individuals, but we have yet to understand both the basic underlying neural mechanisms as well as potential interindividual differences. Using fMRI in combination with a delayed-discrimination task in healthy volunteers of both sexes, we discovered that brain regions involved in this working memory encoding process were dissociable according to whether the to-be-remembered stimulus was painful or not, with the medial thalamus and the rostral anterior cingulate cortex encoding painful and the primary somatosensory cortex encoding nonpainful stimuli. Encoding of painful stimuli furthermore significantly enhanced functional connectivity between the thalamus and medial prefrontal cortex (mPFC). With regards to emotional aspects influencing encoding processes, we observed that more anxious participants showed significant performance advantages when encoding painful stimuli. Importantly, only during the encoding of pain, the interindividual differences in anxiety were associated with the strength of coupling between medial thalamus and mPFC, which was furthermore related to activity in the amygdala. These results indicate not only that there is a distinct signature for the encoding of a painful experience in humans, but also that this encoding process involves a strong affective component. SIGNIFICANCE STATEMENT To convert the sensation of pain into a briefly maintainable construct is essential to guide human behavior and avoid dangerous situations. Although this working memory encoding process is implicitly contained in the majority of studies, the underlying neural mechanisms remain unclear. Using fMRI in a delayed-discrimination task, we found that the encoding of pain engaged the activation of the medial thalamus and the functional connectivity between the thalamus and medial prefrontal cortex. These fMRI data were directly and indirectly related to participants' self-reported trait and state anxiety. Our findings indicate that the mechanisms responsible for the encoding of noxious stimuli differ from those for the encoding of innocuous stimuli, and that these mechanisms are shaped by an individual's anxiety levels.
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20
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Furth KE, McCoy AJ, Dodge C, Walters JR, Buonanno A, Delaville C. Neuronal correlates of ketamine and walking induced gamma oscillations in the medial prefrontal cortex and mediodorsal thalamus. PLoS One 2017; 12:e0186732. [PMID: 29095852 PMCID: PMC5667758 DOI: 10.1371/journal.pone.0186732] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2017] [Accepted: 10/08/2017] [Indexed: 01/19/2023] Open
Abstract
Alterations in the function of the medial prefrontal cortex (mPFC) and its major thalamic source of innervation, the mediodorsal (MD) thalamus, have been hypothesized to contribute to the symptoms of schizophrenia. The NMDAR antagonist ketamine, used to model schizophrenia, elicits a brain state resembling early stage schizophrenia characterized by cognitive deficits and increases in cortical low gamma (40-70 Hz) power. Here we sought to determine how ketamine differentially affects spiking and gamma local field potential (LFP) activity in the rat mPFC and MD thalamus. Additionally, we investigated the ability of drugs targeting the dopamine D4 receptor (D4R) to modify the effects of ketamine on gamma activity as a measure of potential cognitive therapeutic efficacy. Rats were trained to walk on a treadmill to reduce confounds related to hyperactivity after ketamine administration (10 mg/kg s.c.) while recordings were obtained from electrodes chronically implanted in the mPFC and MD thalamus. Ketamine increased gamma LFP power in mPFC and MD thalamus in a similar frequency range, yet did not increase thalamocortical synchronization. Ketamine also increased firing rates and spike synchronization to gamma oscillations in the mPFC but decreased both measures in MD thalamus. Conversely, walking alone increased both firing rates and spike-gamma LFP correlations in both mPFC and MD thalamus. The D4R antagonist alone (L-745,870) had no effect on gamma LFP power during treadmill walking, although it reversed increases induced by the D4R agonist (A-412997) in both mPFC and MD thalamus. Neither drug altered ketamine-induced changes in gamma power or firing rates in the mPFC. However, in MD thalamus, the D4R agonist increased ketamine-induced gamma power and prevented ketamine's inhibitory effect on firing rates. Results provide new evidence that ketamine differentially modulates spiking and gamma power in MD thalamus and mPFC, supporting a potential role for both areas in contributing to ketamine-induced schizophrenia-like symptoms.
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Affiliation(s)
- Katrina E. Furth
- Neurophysiological Pharmacology Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, United States of America
- Graduate Program for Neuroscience, Boston University, Boston, Massachusetts, United States of America
- Section on Molecular Neurobiology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Alex J. McCoy
- Neurophysiological Pharmacology Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Caroline Dodge
- Neurophysiological Pharmacology Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Judith R. Walters
- Neurophysiological Pharmacology Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Andres Buonanno
- Section on Molecular Neurobiology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland, United States of America
| | - Claire Delaville
- Neurophysiological Pharmacology Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland, United States of America
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21
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von Bartheld CS. Myths and truths about the cellular composition of the human brain: A review of influential concepts. J Chem Neuroanat 2017; 93:2-15. [PMID: 28873338 DOI: 10.1016/j.jchemneu.2017.08.004] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2017] [Revised: 08/16/2017] [Accepted: 08/17/2017] [Indexed: 11/17/2022]
Abstract
Over the last 50 years, quantitative methodology has made important contributions to our understanding of the cellular composition of the human brain. Not all of the concepts that emerged from quantitative studies have turned out to be true. Here, I examine the history and current status of some of the most influential notions. This includes claims of how many cells compose the human brain, and how different cell types contribute and in what ratios. Additional concepts entail whether we lose significant numbers of neurons with normal aging, whether chronic alcohol abuse contributes to cortical neuron loss, whether there are significant differences in the quantitative composition of cerebral cortex between male and female brains, whether superior intelligence in humans correlates with larger numbers of brain cells, and whether there are secular (generational) changes in neuron number. Do changes in cell number or changes in ratios of cell types accompany certain diseases, and should all counting methods, even the theoretically unbiased ones, be validated and calibrated? I here examine the origin and the current status of major influential concepts, and I review the evidence and arguments that have led to either confirmation or refutation of such concepts. I discuss the circumstances, assumptions and mindsets that perpetuated erroneous views, and the types of technological advances that have, in some cases, challenged longstanding ideas. I will acknowledge the roles of key proponents of influential concepts in the sometimes convoluted path towards recognition of the true cellular composition of the human brain.
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Affiliation(s)
- Christopher S von Bartheld
- Department of Physiology and Cell Biology, University of Nevada, Reno School of Medicine, Mailstop 352, Reno, NV 89557, USA.
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22
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Scott BH, Saleem KS, Kikuchi Y, Fukushima M, Mishkin M, Saunders RC. Thalamic connections of the core auditory cortex and rostral supratemporal plane in the macaque monkey. J Comp Neurol 2017; 525:3488-3513. [PMID: 28685822 DOI: 10.1002/cne.24283] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2016] [Revised: 06/29/2017] [Accepted: 06/30/2017] [Indexed: 01/06/2023]
Abstract
In the primate auditory cortex, information flows serially in the mediolateral dimension from core, to belt, to parabelt. In the caudorostral dimension, stepwise serial projections convey information through the primary, rostral, and rostrotemporal (AI, R, and RT) core areas on the supratemporal plane, continuing to the rostrotemporal polar area (RTp) and adjacent auditory-related areas of the rostral superior temporal gyrus (STGr) and temporal pole. In addition to this cascade of corticocortical connections, the auditory cortex receives parallel thalamocortical projections from the medial geniculate nucleus (MGN). Previous studies have examined the projections from MGN to auditory cortex, but most have focused on the caudal core areas AI and R. In this study, we investigated the full extent of connections between MGN and AI, R, RT, RTp, and STGr using retrograde and anterograde anatomical tracers. Both AI and R received nearly 90% of their thalamic inputs from the ventral subdivision of the MGN (MGv; the primary/lemniscal auditory pathway). By contrast, RT received only ∼45% from MGv, and an equal share from the dorsal subdivision (MGd). Area RTp received ∼25% of its inputs from MGv, but received additional inputs from multisensory areas outside the MGN (30% in RTp vs. 1-5% in core areas). The MGN input to RTp distinguished this rostral extension of auditory cortex from the adjacent auditory-related cortex of the STGr, which received 80% of its thalamic input from multisensory nuclei (primarily medial pulvinar). Anterograde tracers identified complementary descending connections by which highly processed auditory information may modulate thalamocortical inputs.
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Affiliation(s)
- Brian H Scott
- Laboratory of Neuropsychology, National Institute of Mental Health, National Institutes of Health (NIMH/NIH), Bethesda, Maryland
| | - Kadharbatcha S Saleem
- Laboratory of Neuropsychology, National Institute of Mental Health, National Institutes of Health (NIMH/NIH), Bethesda, Maryland
| | - Yukiko Kikuchi
- Laboratory of Neuropsychology, National Institute of Mental Health, National Institutes of Health (NIMH/NIH), Bethesda, Maryland
| | - Makoto Fukushima
- Laboratory of Neuropsychology, National Institute of Mental Health, National Institutes of Health (NIMH/NIH), Bethesda, Maryland
| | - Mortimer Mishkin
- Laboratory of Neuropsychology, National Institute of Mental Health, National Institutes of Health (NIMH/NIH), Bethesda, Maryland
| | - Richard C Saunders
- Laboratory of Neuropsychology, National Institute of Mental Health, National Institutes of Health (NIMH/NIH), Bethesda, Maryland
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23
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Yuan R, Taylor PA, Alvarez TL, Misra D, Biswal BB. MAPBOT: Meta-analytic parcellation based on text, and its application to the human thalamus. Neuroimage 2017. [PMID: 28629976 DOI: 10.1016/j.neuroimage.2017.06.032] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Meta-analysis of neuroimaging results has proven to be a popular and valuable method to study human brain functions. A number of studies have used meta-analysis to parcellate distinct brain regions. A popular way to perform meta-analysis is typically based on the reported activation coordinates from a number of published papers. However, in addition to the coordinates associated with the different brain regions, the text itself contains considerably amount of additional information. This textual information has been largely ignored in meta-analyses where it may be useful for simultaneously parcellating brain regions and studying their characteristics. By leveraging recent advances in document clustering techniques, we introduce an approach to parcellate the brain into meaningful regions primarily based on the text features present in a document from a large number of studies. This new method is called MAPBOT (Meta-Analytic Parcellation Based On Text). Here, we first describe how the method works and then the application case of understanding the sub-divisions of the thalamus. The thalamus was chosen because of the substantial body of research that has been reported studying this functional and structural structure for both healthy and clinical populations. However, MAPBOT is a general-purpose method that is applicable to parcellating any region(s) of the brain. The present study demonstrates the powerful utility of using text information from neuroimaging studies to parcellate brain regions.
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Affiliation(s)
- Rui Yuan
- Department of Biomedical Engineering, New Jersey Institute of Technology, Newark, NJ 07102, USA; Department of Electrical Engineering, New Jersey Institute of Technology, Newark, NJ 07102, USA
| | - Paul A Taylor
- Scientific and Statistical Computing Core, National Institute of Mental Health, National Institutes of Health, Department of Health and Human Services, USA
| | - Tara L Alvarez
- Department of Biomedical Engineering, New Jersey Institute of Technology, Newark, NJ 07102, USA
| | - Durga Misra
- Department of Electrical Engineering, New Jersey Institute of Technology, Newark, NJ 07102, USA
| | - Bharat B Biswal
- Department of Biomedical Engineering, New Jersey Institute of Technology, Newark, NJ 07102, USA; Department of Radiology, Rutgers, The State University of New Jersey, Newark, NJ 07102, USA.
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Postmortem structural studies of the thalamus in schizophrenia. Schizophr Res 2017; 180:28-35. [PMID: 27567291 PMCID: PMC5746188 DOI: 10.1016/j.schres.2016.08.007] [Citation(s) in RCA: 65] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Revised: 08/05/2016] [Accepted: 08/08/2016] [Indexed: 01/03/2023]
Abstract
In this review, we seek to answer the following question: Do findings in the current literature support the idea that thalamo-cortical dysfunction in schizophrenia is due to structural abnormalities in the thalamus? We base our review on the existing literature of design-unbiased stereological studies of the postmortem thalamus from subjects with schizophrenia. Thus, all reported results are based upon the use of unbiased principles of sampling to determine volume and/or total cell numbers of thalamus or its constituent nuclei. We found 28 such papers covering 26 studies. In a series of tables we list all positive and negative findings from the total thalamus, the mediodorsal, pulvinar and anterior nuclei, as well as less frequently studied thalamic regions. Only four studies examined the entire thalamus and the results were inconsistent. We found largely consistent evidence for structural changes (reduced volume and cell numbers) in the pulvinar located in the posterior thalamus. In contrast, findings in the mediodorsal thalamic nucleus are inconsistent, with the largest and most recent studies generally failing to support earlier reports of a lower number of neurons in schizophrenia. Thus, the current findings of stereological studies of the thalamus in schizophrenia support the idea that thalamo-cortical dysfunction in schizophrenia might be attributable, at least in part, to structural alterations in the pulvinar that could impair thalamic inputs to higher order cortical association areas in the frontal and parietal lobes. However, more studies are needed before robust conclusions can be drawn.
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Giraldo-Chica M, Woodward ND. Review of thalamocortical resting-state fMRI studies in schizophrenia. Schizophr Res 2017; 180:58-63. [PMID: 27531067 PMCID: PMC5297399 DOI: 10.1016/j.schres.2016.08.005] [Citation(s) in RCA: 140] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/02/2016] [Revised: 08/03/2016] [Accepted: 08/06/2016] [Indexed: 12/19/2022]
Abstract
Brain circuitry underlying cognition, emotion, and perception is abnormal in schizophrenia. There is considerable evidence that the neuropathology of schizophrenia includes the thalamus, a key hub of cortical-subcortical circuitry and an important regulator of cortical activity. However, the thalamus is a heterogeneous structure composed of several nuclei with distinct inputs and cortical connections. Limitations of conventional neuroimaging methods and conflicting findings from post-mortem investigations have made it difficult to determine if thalamic pathology in schizophrenia is widespread or limited to specific thalamocortical circuits. Resting-state fMRI has proven invaluable for understanding the large-scale functional organization of the brain and investigating neural circuitry relevant to psychiatric disorders. This article summarizes resting-state fMRI investigations of thalamocortical functional connectivity in schizophrenia. Particular attention is paid to the course, diagnostic specificity, and clinical correlates of thalamocortical network dysfunction.
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Schmitt LI, Halassa MM. Interrogating the mouse thalamus to correct human neurodevelopmental disorders. Mol Psychiatry 2017; 22:183-191. [PMID: 27725660 PMCID: PMC5258688 DOI: 10.1038/mp.2016.183] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Revised: 08/03/2016] [Accepted: 08/25/2016] [Indexed: 11/09/2022]
Abstract
While localizing sensory and motor deficits is one of the cornerstones of clinical neurology, behavioral and cognitive deficits in psychiatry remain impervious to this approach. In psychiatry, major challenges include the relative subtlety by which neural circuits are perturbed, and the limited understanding of how basic circuit functions relate to thought and behavior. Neurodevelopmental disorders offer a window to addressing the first challenge given their strong genetic underpinnings, which can be linked to biological mechanisms. Such links have benefited from genetic modeling in the mouse, and in this review we highlight how this small mammal is now allowing us to crack neural circuits as well. We review recent studies of mouse thalamus, discussing how they revealed general principles that may underlie human perception and attention. Controlling the magnitude (gain) of thalamic sensory responses is a mechanism of attention, and the mouse has enabled its functional dissection at an unprecedented resolution. Further, modeling human genetic neurodevelopmental disease in the mouse has shown how diminished thalamic gain control can lead to attention deficits. This breaks new ground in how we untangle the complexity of psychiatric diseases; by making thalamic circuits accessible to mechanistic dissection; the mouse has not only taught us how they fundamentally work, but also how their dysfunction can be precisely mapped onto behavioral and cognitive deficits. Future studies promise even more progress, with the hope that principled targeting of identified thalamic circuits can be uniquely therapeutic.
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Affiliation(s)
- L. Ian Schmitt
- The Neuroscience Institute, New York University School of Medicine, New York, NY
| | - Michael M. Halassa
- The Neuroscience Institute, New York University School of Medicine, New York, NY,Center for Neural Science, New York University, New York, NY,Department of Psychiatry, NYU Langone Medical Center, New York, NY
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27
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von Bartheld CS, Bahney J, Herculano-Houzel S. The search for true numbers of neurons and glial cells in the human brain: A review of 150 years of cell counting. J Comp Neurol 2016; 524:3865-3895. [PMID: 27187682 PMCID: PMC5063692 DOI: 10.1002/cne.24040] [Citation(s) in RCA: 552] [Impact Index Per Article: 69.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2015] [Revised: 05/13/2016] [Accepted: 05/16/2016] [Indexed: 12/13/2022]
Abstract
For half a century, the human brain was believed to contain about 100 billion neurons and one trillion glial cells, with a glia:neuron ratio of 10:1. A new counting method, the isotropic fractionator, has challenged the notion that glia outnumber neurons and revived a question that was widely thought to have been resolved. The recently validated isotropic fractionator demonstrates a glia:neuron ratio of less than 1:1 and a total number of less than 100 billion glial cells in the human brain. A survey of original evidence shows that histological data always supported a 1:1 ratio of glia to neurons in the entire human brain, and a range of 40-130 billion glial cells. We review how the claim of one trillion glial cells originated, was perpetuated, and eventually refuted. We compile how numbers of neurons and glial cells in the adult human brain were reported and we examine the reasons for an erroneous consensus about the relative abundance of glial cells in human brains that persisted for half a century. Our review includes a brief history of cell counting in human brains, types of counting methods that were and are employed, ranges of previous estimates, and the current status of knowledge about the number of cells. We also discuss implications and consequences of the new insights into true numbers of glial cells in the human brain, and the promise and potential impact of the newly validated isotropic fractionator for reliable quantification of glia and neurons in neurological and psychiatric diseases. J. Comp. Neurol. 524:3865-3895, 2016. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
| | - Jami Bahney
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, USA
| | - Suzana Herculano-Houzel
- Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, and Instituto Nacional de Neurociência Translacional, CNPq/MCT, Brasil
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28
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von Bartheld CS, Bahney J, Herculano-Houzel S. The search for true numbers of neurons and glial cells in the human brain: A review of 150 years of cell counting. J Comp Neurol 2016; 524:3865-3895. [PMID: 27187682 DOI: 10.1002/cne.2404] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2015] [Revised: 05/13/2016] [Accepted: 05/16/2016] [Indexed: 05/25/2023]
Abstract
For half a century, the human brain was believed to contain about 100 billion neurons and one trillion glial cells, with a glia:neuron ratio of 10:1. A new counting method, the isotropic fractionator, has challenged the notion that glia outnumber neurons and revived a question that was widely thought to have been resolved. The recently validated isotropic fractionator demonstrates a glia:neuron ratio of less than 1:1 and a total number of less than 100 billion glial cells in the human brain. A survey of original evidence shows that histological data always supported a 1:1 ratio of glia to neurons in the entire human brain, and a range of 40-130 billion glial cells. We review how the claim of one trillion glial cells originated, was perpetuated, and eventually refuted. We compile how numbers of neurons and glial cells in the adult human brain were reported and we examine the reasons for an erroneous consensus about the relative abundance of glial cells in human brains that persisted for half a century. Our review includes a brief history of cell counting in human brains, types of counting methods that were and are employed, ranges of previous estimates, and the current status of knowledge about the number of cells. We also discuss implications and consequences of the new insights into true numbers of glial cells in the human brain, and the promise and potential impact of the newly validated isotropic fractionator for reliable quantification of glia and neurons in neurological and psychiatric diseases. J. Comp. Neurol. 524:3865-3895, 2016. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
| | - Jami Bahney
- Department of Physiology and Cell Biology, University of Nevada School of Medicine, Reno, Nevada, USA
| | - Suzana Herculano-Houzel
- Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, and Instituto Nacional de Neurociência Translacional, CNPq/MCT, Brasil
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29
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Nagalski A, Puelles L, Dabrowski M, Wegierski T, Kuznicki J, Wisniewska MB. Molecular anatomy of the thalamic complex and the underlying transcription factors. Brain Struct Funct 2016; 221:2493-510. [PMID: 25963709 PMCID: PMC4884203 DOI: 10.1007/s00429-015-1052-5] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2014] [Accepted: 04/27/2015] [Indexed: 01/19/2023]
Abstract
Thalamocortical loops have been implicated in the control of higher-order cognitive functions, but advances in our understanding of the molecular underpinnings of neocortical organization have not been accompanied by similar analyses in the thalamus. Using expression-based correlation maps and the manual mapping of mouse and human datasets available in the Allen Brain Atlas, we identified a few individual regions and several sets of molecularly related nuclei that partially overlap with the classic grouping that is based on topographical localization and thalamocortical connections. These new molecular divisions of the adult thalamic complex are defined by the combinatorial expression of Tcf7l2, Lef1, Gbx2, Prox1, Pou4f1, Esrrg, and Six3 transcription factor genes. Further in silico and experimental analyses provided the evidence that TCF7L2 might be a pan-thalamic specifier. These results provide substantial insights into the "molecular logic" that underlies organization of the thalamic complex.
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Affiliation(s)
- Andrzej Nagalski
- Laboratory of Neurodegeneration, International Institute of Molecular and Cell Biology, Warsaw, 02-109, Poland
- Laboratory of Molecular Neurobiology, Centre of New Technologies, University of Warsaw, Warsaw, 00-927, Poland
| | - Luis Puelles
- Department of Human Anatomy, University of Murcia and IMIB, Murcia, 30071, Spain
| | - Michal Dabrowski
- Laboratory of Bioinformatics, Center of Neurobiology, Nencki Institute of Experimental Biology, Warsaw, 02-093, Poland
| | - Tomasz Wegierski
- Laboratory of Neurodegeneration, International Institute of Molecular and Cell Biology, Warsaw, 02-109, Poland
| | - Jacek Kuznicki
- Laboratory of Neurodegeneration, International Institute of Molecular and Cell Biology, Warsaw, 02-109, Poland
| | - Marta B Wisniewska
- Laboratory of Neurodegeneration, International Institute of Molecular and Cell Biology, Warsaw, 02-109, Poland.
- Laboratory of Molecular Neurobiology, Centre of New Technologies, University of Warsaw, Warsaw, 00-927, Poland.
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DNA Damage in Major Psychiatric Diseases. Neurotox Res 2016; 30:251-67. [PMID: 27126805 DOI: 10.1007/s12640-016-9621-9] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Revised: 03/31/2016] [Accepted: 04/09/2016] [Indexed: 12/21/2022]
Abstract
Human cells are exposed to exogenous insults and continuous production of different metabolites. These insults and unwanted metabolic products might interfere with the stability of genomic DNA. Recently, many studies have demonstrated that different psychiatric disorders show substantially high levels of oxidative DNA damage in the brain accompanied with morphological and functional alterations. It reveals that damaged genomic DNA may contribute to the pathophysiology of these mental illnesses. In this article, we review the roles of oxidative damage and reduced antioxidant ability in some vastly studied psychiatric disorders and emphasize the inclusion of treatment options involving DNA repair. In addition, while most currently used antidepressants are based on the manipulation of the neurotransmitter regulation in managing different mental abnormalities, they are able to prevent or reverse neurotoxin-induced DNA damage. Therefore, it may be plausible to target on genomic DNA alterations for psychiatric therapies, which is of pivotal importance for future antipsychiatric drug development.
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Lewis DA, Glausier JR. Alterations in Prefrontal Cortical Circuitry and Cognitive Dysfunction in Schizophrenia. NEBRASKA SYMPOSIUM ON MOTIVATION. NEBRASKA SYMPOSIUM ON MOTIVATION 2016; 63:31-75. [PMID: 27627824 DOI: 10.1007/978-3-319-30596-7_3] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
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Bakhshi K, Chance S. The neuropathology of schizophrenia: A selective review of past studies and emerging themes in brain structure and cytoarchitecture. Neuroscience 2015; 303:82-102. [DOI: 10.1016/j.neuroscience.2015.06.028] [Citation(s) in RCA: 92] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2014] [Revised: 06/16/2015] [Accepted: 06/17/2015] [Indexed: 01/12/2023]
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33
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Tu PC, Lee YC, Chen YS, Hsu JW, Li CT, Su TP. Network-specific cortico-thalamic dysconnection in schizophrenia revealed by intrinsic functional connectivity analyses. Schizophr Res 2015; 166:137-43. [PMID: 26081977 DOI: 10.1016/j.schres.2015.05.023] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/13/2014] [Revised: 04/15/2015] [Accepted: 05/01/2015] [Indexed: 11/29/2022]
Abstract
BACKGROUND Cortico-thalamic connections are thought to be abnormal in schizophrenia due to their important roles in sensory relay and higher cognitive control, both of which are affected by this devastating illness. This study tested the cortico-thalamic dysconnection hypothesis in schizophrenia and further explored cortico-thalamic network properties using functional connectivity MRI (fcMRI). METHODS Forty-eight participants with schizophrenia and 48 healthy controls underwent resting fMRI scans and clinical evaluations. Six a priori cortical regions of interests (ROIs) were used to derive the six networks: dorsal default mode network (dDMN), fronto-parietal network (FPN), cingulo-opercular network (CON), primary sensorimotor network (SM1), primary auditory network (A1) and primary visual network (V1). The cortico-thalamic connectivity for each network was calculated for each participant and then compared between groups. RESULTS A repeated measures analysis of variance (ANOVA) showed significant group×network interactions (F(5, 90)=9.5, P<0.001), which were driven by a significant increase in FC within the SM1 (t(94)=4.1, P<0.001) and A1 (t(94)=4.2, P<0.001) networks in schizophrenics, as well as a significant decrease within the CON (t(94)=-2.8, P=0.04). The cortico-thalamic dysconnection did not correlate with symptom severity, representing a state independent abnormality. CONCLUSION The network analysis indicates that cortico-thalamic dysconnection in schizophrenia involves multiple networks and shows network specific changes. The findings provide support for dysfunctional thalamus-related networks in schizophrenia and further elaborate their network properties.
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Affiliation(s)
- Pei-Chi Tu
- Department of Medical Research and Education, Taipei Veterans General Hospital, Taipei 112, Taiwan; Department of Psychiatry, Taipei Veterans General Hospital, Taipei 112, Taiwan; Institute of Philosophy of Mind and Cognition, National Yang-Ming University, Taipei, Taiwan; Department of Psychiatry, Faculty of Medicine, National Yang-Ming University, Taipei, Taiwan
| | - Ying-Chiao Lee
- Department of Psychiatry, Taipei Veterans General Hospital, Taipei 112, Taiwan; Department of Psychiatry, Faculty of Medicine, National Yang-Ming University, Taipei, Taiwan
| | - Ying-Shiue Chen
- Department of Psychiatry, Taipei Veterans General Hospital, Taipei 112, Taiwan; Department of Psychiatry, Faculty of Medicine, National Yang-Ming University, Taipei, Taiwan
| | - Ju-Wei Hsu
- Department of Psychiatry, Taipei Veterans General Hospital, Taipei 112, Taiwan; Department of Psychiatry, Faculty of Medicine, National Yang-Ming University, Taipei, Taiwan
| | - Cheng-Ta Li
- Department of Psychiatry, Taipei Veterans General Hospital, Taipei 112, Taiwan; Department of Psychiatry, Faculty of Medicine, National Yang-Ming University, Taipei, Taiwan
| | - Tung-Ping Su
- Department of Psychiatry, Taipei Veterans General Hospital, Taipei 112, Taiwan; Department of Psychiatry, Faculty of Medicine, National Yang-Ming University, Taipei, Taiwan.
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The role of the thalamus in schizophrenia from a neuroimaging perspective. Neurosci Biobehav Rev 2015; 54:57-75. [DOI: 10.1016/j.neubiorev.2015.01.013] [Citation(s) in RCA: 122] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2014] [Revised: 12/19/2014] [Accepted: 01/12/2015] [Indexed: 02/06/2023]
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Delta frequency optogenetic stimulation of the thalamic nucleus reuniens is sufficient to produce working memory deficits: relevance to schizophrenia. Biol Psychiatry 2015; 77:1098-107. [PMID: 25891221 PMCID: PMC4444380 DOI: 10.1016/j.biopsych.2015.01.020] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/18/2014] [Revised: 01/05/2015] [Accepted: 01/15/2015] [Indexed: 01/01/2023]
Abstract
BACKGROUND Low-frequency (delta/theta) oscillations in the thalamocortical system are elevated in schizophrenia during wakefulness and are also induced in the N-methyl-D-asparate receptor hypofunction rat model. To determine whether abnormal delta oscillations might produce functional deficits, we used optogenetic methods in awake rats. We illuminated channelrhodopsin-2 in the thalamic nucleus reuniens (RE) at delta frequency and measured the effect on working memory (WM) performance (the RE is involved in WM, a process affected in schizophrenia [SZ]). METHODS We injected RE with adeno-associated virus to transduce cells with channelrhodopsin-2. An optical fiber was implanted just dorsal to the hippocampus in order to illuminate RE axon terminals. RESULTS During optogenetic delta frequency stimulation, rats displayed a strong WM deficit. On the following day, performance was normal if illumination was omitted. CONCLUSIONS The optogenetic experiments show that delta frequency stimulation of a thalamic nucleus is sufficient to produce deficits in WM. This result supports the hypothesis that delta frequency bursting in particular thalamic nuclei has a causal role in producing WM deficits in SZ. The action potentials in these bursts may "jam" communication through the thalamus, thereby interfering with behaviors dependent on WM. Studies in thalamic slices using the N-methyl-D-asparate receptor hypofunction model show that delta frequency bursting is dependent on T-type Ca(2+) channels, a result that we confirmed here in vivo. These channels, which are strongly implicated in SZ by genome-wide association studies, may thus be a therapeutic target for treatment of SZ.
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Gan X, Xu B, Ji X, Lu W, Waxman D, Feng J. A statistical approach for detecting common features. J Neurosci Methods 2015; 247:1-12. [PMID: 25773994 DOI: 10.1016/j.jneumeth.2015.02.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2014] [Revised: 02/10/2015] [Accepted: 02/11/2015] [Indexed: 11/16/2022]
Abstract
BACKGROUND With increasing numbers of datasets in neuroimaging studies, it has become an important task to pool information, in order to increase the statistical power of tests and for cross validation. However, no robust global approach unambiguously identifies the common biological abnormalities in, for example, resting-state functional magnetic resonance imaging in a number of mental disorders, where there are multiple datasets/attributes. Here we propose a novel and efficient statistical approach to this problem that finds common features in multiple datasets. NEW METHOD By collecting the statistics of each dataset into a vector, our method uses a 'multi-dimensional local false discovery' rate to pool information and make full use of the joint distribution of datasets. RESULTS We have tested our approach extensively on both simulated and clinical datasets. By conducting simulation studies, we find that our approach has a higher statistical power than existing approaches, especially on correlated datasets. Employing our approach on clinical data yields findings that are consistent with the existing literature. COMPARISON WITH EXISTING METHODS Conventional methods cannot determine the false discovery rate underlying multiple datasets/attributes. Our approach can effectively handle these datasets. It has a solid Bayesian interpretation, and a higher power than other approaches in numerical simulations. This can be explained by the incorporation of correlations, between different attributes, into the new method. CONCLUSIONS In this work, we present a natural, novel and powerful statistical approach to tackle situations involving multiple datasets or attributes. This new method has significant advantages over existing approaches and wide applications.
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Affiliation(s)
- Xinjun Gan
- Centre for Computational Systems Biology and School of Mathematical Sciences, Fudan University, Shanghai 200433, PR China
| | - Bing Xu
- Centre for Computational Systems Biology and School of Mathematical Sciences, Fudan University, Shanghai 200433, PR China
| | - Xiaoxi Ji
- Centre for Computational Systems Biology and School of Mathematical Sciences, Fudan University, Shanghai 200433, PR China
| | - Wenlian Lu
- Centre for Computational Systems Biology and School of Mathematical Sciences, Fudan University, Shanghai 200433, PR China; Department of Computer Science, Warwick University, Coventry CV2 7AL, UK
| | - David Waxman
- Centre for Computational Systems Biology and School of Mathematical Sciences, Fudan University, Shanghai 200433, PR China
| | - Jianfeng Feng
- Centre for Computational Systems Biology and School of Mathematical Sciences, Fudan University, Shanghai 200433, PR China; Department of Computer Science, Warwick University, Coventry CV2 7AL, UK; Shanghai Center for Mathematical Sciences, Fudan University, Shanghai 200433, PR China; School of Life Science and the Collaborative Innovation Center for Brain Science, Fudan University, Shanghai 200433, PR China.
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Yuan R, Di X, Taylor PA, Gohel S, Tsai YH, Biswal BB. Functional topography of the thalamocortical system in human. Brain Struct Funct 2015; 221:1971-84. [PMID: 25924563 DOI: 10.1007/s00429-015-1018-7] [Citation(s) in RCA: 87] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2014] [Accepted: 02/24/2015] [Indexed: 12/21/2022]
Abstract
Various studies have indicated that the thalamus is involved in controlling both cortico-cortical information flow and cortical communication with the rest of the brain. Detailed anatomy and functional connectivity patterns of the thalamocortical system are essential to understanding the cortical organization and pathophysiology of a wide range of thalamus-related neurological and neuropsychiatric diseases. The current study used resting-state fMRI to investigate the topography of the human thalamocortical system from a functional perspective. The thalamus-related cortical networks were identified by performing independent component analysis on voxel-based thalamic functional connectivity maps across a large group of subjects. The resulting functional brain networks were very similar to well-established resting-state network maps. Using these brain network components in a spatial regression model with each thalamic voxel's functional connectivity map, we localized the thalamic subdivisions related to each brain network. For instance, the medial dorsal nucleus was shown to be associated with the default mode, the bilateral executive, the medial visual networks; and the pulvinar nucleus was involved in both the dorsal attention and the visual networks. These results revealed that a single nucleus may have functional connections with multiple cortical regions or even multiple functional networks, and may be potentially related to the function of mediation or modulation of multiple cortical networks. This observed organization of thalamocortical system provided a reference for studying the functions of thalamic sub-regions. The importance of intrinsic connectivity-based mapping of the thalamocortical relationship is discussed, as well as the applicability of the approach for future studies.
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Affiliation(s)
- Rui Yuan
- Department of Biomedical Engineering, New Jersey Institute of Technology, University Heights, Newark, NJ, 07102, USA
- Department of Electrical Engineering, New Jersey Institute of Technology, University Heights, Newark, NJ, 07102, USA
| | - Xin Di
- Department of Biomedical Engineering, New Jersey Institute of Technology, University Heights, Newark, NJ, 07102, USA
| | - Paul A Taylor
- MRC/UCT Medical Imaging Research Unit, Department of Human Biology, University of Cape Town, Cape Town, South Africa
- African Institute for Mathematical Sciences, Muizenberg, Western Cape, South Africa
| | - Suril Gohel
- Department of Biomedical Engineering, New Jersey Institute of Technology, University Heights, Newark, NJ, 07102, USA
| | - Yuan-Hsiung Tsai
- Department of Diagnostic Radiology, Chang Gung Memorial Hospital at Chiayi, College of Medicine and School of Medical Technology, Chang-Gung University, Taoyuan, Taiwan
| | - Bharat B Biswal
- Department of Biomedical Engineering, New Jersey Institute of Technology, University Heights, Newark, NJ, 07102, USA.
- Department of Radiology, Rutgers, The State University of New Jersey, Newark, NJ, 07102, USA.
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Herculano-Houzel S, von Bartheld CS, Miller DJ, Kaas JH. How to count cells: the advantages and disadvantages of the isotropic fractionator compared with stereology. Cell Tissue Res 2015; 360:29-42. [PMID: 25740200 DOI: 10.1007/s00441-015-2127-6] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2014] [Accepted: 01/15/2015] [Indexed: 01/12/2023]
Abstract
The number of cells comprising biological structures represents fundamental information in basic anatomy, development, aging, drug tests, pathology and genetic manipulations. Obtaining unbiased estimates of cell numbers, however, was until recently possible only through stereological techniques, which require specific training, equipment, histological processing and appropriate sampling strategies applied to structures with a homogeneous distribution of cell bodies. An alternative, the isotropic fractionator (IF), became available in 2005 as a fast and inexpensive method that requires little training, no specific software and only a few materials before it can be used to quantify total numbers of neuronal and non-neuronal cells in a whole organ such as the brain or any dissectible regions thereof. This method entails transforming a highly anisotropic tissue into a homogeneous suspension of free-floating nuclei that can then be counted under the microscope or by flow cytometry and identified morphologically and immunocytochemically as neuronal or non-neuronal. We compare the advantages and disadvantages of each method and provide researchers with guidelines for choosing the best method for their particular needs. IF is as accurate as unbiased stereology and faster than stereological techniques, as it requires no elaborate histological processing or sampling paradigms, providing reliable estimates in a few days rather than many weeks. Tissue shrinkage is also not an issue, since the estimates provided are independent of tissue volume. The main disadvantage of IF, however, is that it necessarily destroys the tissue analyzed and thus provides no spatial information on the cellular composition of biological regions of interest.
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Affiliation(s)
- Suzana Herculano-Houzel
- Instituto de Ciências Biomédicas, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil,
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Ferguson BR, Gao WJ. Development of thalamocortical connections between the mediodorsal thalamus and the prefrontal cortex and its implication in cognition. Front Hum Neurosci 2015; 8:1027. [PMID: 25620923 PMCID: PMC4288125 DOI: 10.3389/fnhum.2014.01027] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2014] [Accepted: 12/05/2014] [Indexed: 01/09/2023] Open
Abstract
The mediodorsal thalamus (MD) represents a fundamental subcortical relay to the prefrontal cortex (PFC), and is thought to be highly implicated in modulation of cognitive performance. Additionally, it undergoes highly conserved developmental stages, which, when dysregulated, can have detrimental consequences. Embryonically, the MD experiences a tremendous surge in neurogenesis and differentiation, and disruption of this process may underlie the pathology in certain neurodevelopmental disorders. However, during the postnatal period, a vast amount of cell loss in the MD occurs. These together may represent an extended critical period for postnatal development, in which disturbances in the normal growth or reduction of the MD afferents to the PFC, can result in PFC-dependent cognitive, affective, or psychotic abnormalities. In this review, we explore the current knowledge supporting this hypothesis of a protracted critical period, and propose how developmental changes in the MD contribute to successful prefrontal cortical development and function. Specifically, we elaborate on the unique properties of MD-PFC connections compared with other thalamocortical afferents in sensory cortices, examine how MD-PFC innervation modulates synaptic transmission in the local prefrontal circuitry, and speculate on what occurs during postnatal development, particularly within the early neonatal stage, as well as juvenile and adolescent periods. Finally, we discuss the questions that remain and propose future experiments in order to provide perspective and novel insights into the cause of neuropsychiatric disorders associated with MD-PFC development.
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Affiliation(s)
- Brielle R Ferguson
- Department of Neurobiology and Anatomy, Drexel University College of Medicine Philadelphia, PA, USA
| | - Wen-Jun Gao
- Department of Neurobiology and Anatomy, Drexel University College of Medicine Philadelphia, PA, USA
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40
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Vukadinovic Z. Elevated striatal dopamine attenuates nigrothalamic inputs and impairs transthalamic cortico-cortical communication in schizophrenia: A hypothesis. Med Hypotheses 2015; 84:47-52. [DOI: 10.1016/j.mehy.2014.11.014] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2014] [Revised: 10/28/2014] [Accepted: 11/11/2014] [Indexed: 12/12/2022]
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41
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Karlsen A, Korbo S, Uylings H, Pakkenberg B. A stereological study of the mediodorsal thalamic nucleus in Down syndrome. Neuroscience 2014; 279:253-9. [DOI: 10.1016/j.neuroscience.2014.08.046] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2014] [Revised: 08/15/2014] [Accepted: 08/31/2014] [Indexed: 11/28/2022]
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42
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Saalmann YB. Intralaminar and medial thalamic influence on cortical synchrony, information transmission and cognition. Front Syst Neurosci 2014; 8:83. [PMID: 24847225 PMCID: PMC4023070 DOI: 10.3389/fnsys.2014.00083] [Citation(s) in RCA: 202] [Impact Index Per Article: 20.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2013] [Accepted: 04/21/2014] [Indexed: 11/15/2022] Open
Abstract
The intralaminar and medial thalamic nuclei are part of the higher-order thalamus, which receives little sensory input, and instead forms extensive cortico-thalamo-cortical pathways. The large mediodorsal thalamic nucleus predominantly connects with the prefrontal cortex, the adjacent intralaminar nuclei connect with fronto-parietal cortex, and the midline thalamic nuclei connect with medial prefrontal cortex and medial temporal lobe. Taking into account this connectivity pattern, it is not surprising that the intralaminar and medial thalamus has been implicated in a variety of cognitive functions, including memory processing, attention and orienting, as well as reward-based behavior. This review addresses how the intralaminar and medial thalamus may regulate information transmission in cortical circuits. A key neural mechanism may involve intralaminar and medial thalamic neurons modulating the degree of synchrony between different groups of cortical neurons according to behavioral demands. Such a thalamic-mediated synchronization mechanism may give rise to large-scale integration of information across multiple cortical circuits, consequently influencing the level of arousal and consciousness. Overall, the growing evidence supports a general role for the higher-order thalamus in the control of cortical information transmission and cognitive processing.
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Affiliation(s)
- Yuri B Saalmann
- Department of Psychology, University of Wisconsin-Madison Madison, WI, USA
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43
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Boeckx C, Benítez-Burraco A. The shape of the human language-ready brain. Front Psychol 2014; 5:282. [PMID: 24772099 PMCID: PMC3983487 DOI: 10.3389/fpsyg.2014.00282] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2013] [Accepted: 03/17/2014] [Indexed: 12/14/2022] Open
Abstract
Our core hypothesis is that the emergence of our species-specific language-ready brain ought to be understood in light of the developmental changes expressed at the levels of brain morphology and neural connectivity that occurred in our species after the split from Neanderthals–Denisovans and that gave us a more globular braincase configuration. In addition to changes at the cortical level, we hypothesize that the anatomical shift that led to globularity also entailed significant changes at the subcortical level. We claim that the functional consequences of such changes must also be taken into account to gain a fuller understanding of our linguistic capacity. Here we focus on the thalamus, which we argue is central to language and human cognition, as it modulates fronto-parietal activity. With this new neurobiological perspective in place, we examine its possible molecular basis. We construct a candidate gene set whose members are involved in the development and connectivity of the thalamus, in the evolution of the human head, and are known to give rise to language-associated cognitive disorders. We submit that the new gene candidate set opens up new windows into our understanding of the genetic basis of our linguistic capacity. Thus, our hypothesis aims at generating new testing grounds concerning core aspects of language ontogeny and phylogeny.
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Affiliation(s)
- Cedric Boeckx
- Catalan Institute for Advanced Studies and Research (ICREA) Barcelona, Spain ; Department of Linguistics, Universitat de Barcelona Barcelona, Spain
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Guillozet-Bongaarts AL, Hyde TM, Dalley RA, Hawrylycz MJ, Henry A, Hof PR, Hohmann J, Jones AR, Kuan CL, Royall J, Shen E, Swanson B, Zeng H, Kleinman JE. Altered gene expression in the dorsolateral prefrontal cortex of individuals with schizophrenia. Mol Psychiatry 2014; 19:478-85. [PMID: 23528911 PMCID: PMC3965839 DOI: 10.1038/mp.2013.30] [Citation(s) in RCA: 81] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/01/2012] [Revised: 01/24/2013] [Accepted: 02/06/2013] [Indexed: 01/31/2023]
Abstract
The underlying pathology of schizophrenia (SZ) is likely as heterogeneous as its symptomatology. A variety of cortical and subcortical regions, including the prefrontal cortex, have been implicated in its pathology, and a number of genes have been identified as risk factors for disease development. We used in situ hybridization (ISH) to examine the expression of 58 genes in the dorsolateral prefrontal cortex (DLPFC, comprised of Brodmann areas 9 and 46) from 19 individuals with a premorbid diagnosis of SZ and 33 control individuals. Genes were selected based on: (1) previous identification as risk factors for SZ; (2) cell type markers or (3) laminar markers. Cell density and staining intensity were compared in the DLPFC, as well as separately in Brodmann areas 9 and 46. The expression patterns of a variety of genes, many of which are associated with the GABAergic system, were altered in SZ when compared with controls. Additional genes, including C8orf79 and NR4A2, showed alterations in cell density or staining intensity between the groups, highlighting the need for additional studies. Alterations were, with only a few exceptions, limited to Brodmann area 9, suggesting regional specificity of pathology in the DLPFC. Our results agree with previous studies on the GABAergic involvement in SZ, and suggest that areas 9 and 46 may be differentially affected in the disease. This study also highlights additional genes that may be altered in SZ, and indicates that these potentially interesting genes can be identified by ISH and high-throughput image analysis techniques.
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Affiliation(s)
- A L Guillozet-Bongaarts
- Allen Institute for Brain Science, Seattle, WA, USA,Data Annotations and Analysis, Allen Institute for Brain Science, 551North 34th Street, Seattle, WA 98103, USA. E-mail:
| | - T M Hyde
- Lieber Institute for Brain Development, Johns Hopkins Medical Campus, Baltimore, MD, USA,Clinical Brain Disorders Branch, Genes Cognition and Psychosis Program, Intramural Research Program, NIMH, NIH, Bethesda, MD, USA,Department of Psychiatry and Behavioral Sciences, and Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - R A Dalley
- Allen Institute for Brain Science, Seattle, WA, USA
| | | | - A Henry
- Allen Institute for Brain Science, Seattle, WA, USA
| | - P R Hof
- Fishberg Department of Neuroscience and Friedman Brain Institute, Icahn School of Medicine, Mount Sinai, New York, NY, USA
| | - J Hohmann
- Allen Institute for Brain Science, Seattle, WA, USA
| | - A R Jones
- Allen Institute for Brain Science, Seattle, WA, USA
| | - C L Kuan
- Allen Institute for Brain Science, Seattle, WA, USA
| | - J Royall
- Allen Institute for Brain Science, Seattle, WA, USA
| | - E Shen
- Allen Institute for Brain Science, Seattle, WA, USA
| | - B Swanson
- Allen Institute for Brain Science, Seattle, WA, USA
| | - H Zeng
- Allen Institute for Brain Science, Seattle, WA, USA
| | - J E Kleinman
- Lieber Institute for Brain Development, Johns Hopkins Medical Campus, Baltimore, MD, USA,Clinical Brain Disorders Branch, Genes Cognition and Psychosis Program, Intramural Research Program, NIMH, NIH, Bethesda, MD, USA
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Klingner CM, Langbein K, Dietzek M, Smesny S, Witte OW, Sauer H, Nenadic I. Thalamocortical connectivity during resting state in schizophrenia. Eur Arch Psychiatry Clin Neurosci 2014; 264:111-9. [PMID: 23892770 DOI: 10.1007/s00406-013-0417-0] [Citation(s) in RCA: 88] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/02/2013] [Accepted: 06/15/2013] [Indexed: 12/21/2022]
Abstract
Schizophrenia has been linked to disturbed connectivity between large-scale brain networks. Altered thalamocortical connectivity might be a major mechanism mediating regionally distributed dysfunction, yet it is only incompletely understood. We analysed functional magnetic resonance imaging data obtained during resting state from 22 DSM-IV schizophrenia patients and 22 matched healthy controls to directly assess the differences in thalamocortical functional connectivity. We identified significantly higher overall thalamocortical functional connectivity in patients, which was mostly accounted for by difference in thalamic connections to right ventrolateral prefrontal and bilateral secondary motor and sensory (superior temporal and lateral occipital) cortical areas. Voxelwise analysis showed group differences at the thalamic level to be mostly in medial and anterior thalamic nuclei and arising thalamocortical changes to be mostly due to higher positive correlations in prefrontal and superior temporal correlations, as well as absent negative correlations to sensory areas in patients. Our findings demonstrate that different types of thalamocortical dysfunction contribute to network alterations, including lack of inhibitory interaction attributed to the lack of significant negative thalamic/sensory cortical connections. These results emphasize the functional importance of the thalamus in the pathophysiology of schizophrenia.
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Affiliation(s)
- Carsten M Klingner
- Department of Psychiatry and Psychotherapy, Jena University Hospital, Philosophenweg 3, 07743, Jena, Germany
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Fuxe K, Borroto-Escuela DO, Romero-Fernandez W, Palkovits M, Tarakanov AO, Ciruela F, Agnati LF. Moonlighting proteins and protein-protein interactions as neurotherapeutic targets in the G protein-coupled receptor field. Neuropsychopharmacology 2014; 39:131-55. [PMID: 24105074 PMCID: PMC3857668 DOI: 10.1038/npp.2013.242] [Citation(s) in RCA: 72] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/18/2013] [Revised: 07/04/2013] [Accepted: 07/05/2013] [Indexed: 12/28/2022]
Abstract
There is serious interest in understanding the dynamics of the receptor-receptor and receptor-protein interactions in space and time and their integration in GPCR heteroreceptor complexes of the CNS. Moonlighting proteins are special multifunctional proteins because they perform multiple autonomous, often unrelated, functions without partitioning into different protein domains. Moonlighting through receptor oligomerization can be operationally defined as an allosteric receptor-receptor interaction, which leads to novel functions of at least one receptor protomer. GPCR-mediated signaling is a more complicated process than previously described as every GPCR and GPCR heteroreceptor complex requires a set of G protein interacting proteins, which interacts with the receptor in an orchestrated spatio-temporal fashion. GPCR heteroreceptor complexes with allosteric receptor-receptor interactions operating through the receptor interface have become major integrative centers at the molecular level and their receptor protomers act as moonlighting proteins. The GPCR heteroreceptor complexes in the CNS have become exciting new targets for neurotherapeutics in Parkinson's disease, schizophrenia, drug addiction, and anxiety and depression opening a new field in neuropsychopharmacology.
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Affiliation(s)
- Kjell Fuxe
- Department of Neuroscience, Karolinska Institutet,, Stockholm, Sweden
| | | | | | - Miklós Palkovits
- Department of Anatomy, Histology and Embryology, Hungarian Academy of Sciences and Semmelweis University, Budapest, Hungary
| | - Alexander O Tarakanov
- Russian Academy of Sciences, St. Petersburg Institute for Informatics and Automation, Saint Petersburg, Russia
| | - Francisco Ciruela
- Facultat de Medicina, Departament de Patologia i Terapèutica Experimental IDIBELL-Universitat de Barcelona, L'Hospitalet de Llobregat, Unitat de Farmacologia, Barcelona, Spain
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47
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Pergola G, Suchan B. Associative learning beyond the medial temporal lobe: many actors on the memory stage. Front Behav Neurosci 2013; 7:162. [PMID: 24312029 PMCID: PMC3832901 DOI: 10.3389/fnbeh.2013.00162] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2013] [Accepted: 10/28/2013] [Indexed: 12/23/2022] Open
Abstract
Decades of research have established a model that includes the medial temporal lobe, and particularly the hippocampus, as a critical node for episodic memory. Neuroimaging and clinical studies have shown the involvement of additional cortical and subcortical regions. Among these areas, the thalamus, the retrosplenial cortex, and the prefrontal cortices have been consistently related to episodic memory performance. This article provides evidences that these areas are in different forms and degrees critical for human memory function rather than playing only an ancillary role. First we briefly summarize the functional architecture of the medial temporal lobe with respect to recognition memory and recall. We then focus on the clinical and neuroimaging evidence available on thalamo-prefrontal and thalamo-retrosplenial networks. The role of these networks in episodic memory has been considered secondary, partly because disruption of these areas does not always lead to severe impairments; to account for this evidence, we discuss methodological issues related to the investigation of these regions. We propose that these networks contribute differently to recognition memory and recall, and also that the memory stage of their contribution shows specificity to encoding or retrieval in recall tasks. We note that the same mechanisms may be in force when humans perform non-episodic tasks, e.g., semantic retrieval and mental time travel. Functional disturbance of these networks is related to cognitive impairments not only in neurological disorders, but also in psychiatric medical conditions, such as schizophrenia. Finally we discuss possible mechanisms for the contribution of these areas to memory, including regulation of oscillatory rhythms and long-term potentiation. We conclude that integrity of the thalamo-frontal and the thalamo-retrosplenial networks is necessary for the manifold features of episodic memory.
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Affiliation(s)
- Giulio Pergola
- Department of Basic Medical Science, Neuroscience and Sense Organs, University of Bari ‘Aldo Moro’, Bari, Italy
- Neuroscience Area, International School for Advanced Studies (SISSA), Trieste, Italy
| | - Boris Suchan
- Department of Neuropsychology, Ruhr-University Bochum, Bochum, Germany
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Selemon LD, Friedman HR. Motor stereotypies and cognitive perseveration in non-human primates exposed to early gestational irradiation. Neuroscience 2013; 248:213-24. [PMID: 23769911 PMCID: PMC3823672 DOI: 10.1016/j.neuroscience.2013.06.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2013] [Revised: 05/31/2013] [Accepted: 06/04/2013] [Indexed: 01/18/2023]
Abstract
A number of psychiatric illnesses have been associated with prenatal disturbance of brain development, including autism, attention deficit hyperactivity disorder, and schizophrenia. Individuals afflicted with these disorders exhibit both repetitive motor and cognitive behavior. The potential role that environmental insult to the developing brain may play in generating these aberrant behaviors is unclear. Here we examine the behavioral consequences of an early gestational insult in the non-human primate. Rhesus macaques were exposed to x-irradiation during the first trimester of development to disrupt neurogenesis. The behavior of five fetally irradiated monkeys (FIMs) and five control monkeys (CONs) was observed as they matured from juvenile (1.5 years) to adult ages (4-5 years). Home-cage behavior was indistinguishable in the two groups. In the testing cage, circling was prevalent in both groups at juvenile ages, persisting to adulthood in three of the five FIMs. One FIM executed a ritualized motor sequence marked by semi-circling and undulating head movements. Seven macaques (4 FIMs, 3 CONs) were tested on a spatial Delayed Alternation (DA) task as adults. Perseverative errors and non-perseverative errors were recorded in early stages of the testing, at the 0 delay interval. While performing DA, FIMs made more errors of perseveration than CONs yet the number of total errors committed did not differ between groups. The presence of motor stereotypies and cognitive perseveration in fetally irradiated non-human primates suggests that environmental insult to the embryonic brain may contribute to repetitive motor and cognitive behaviors in neuropsychiatric diseases.
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Affiliation(s)
- L D Selemon
- Department of Neurobiology, Yale University School of Medicine, New Haven, CT, USA.
| | - H R Friedman
- Department of Neurobiology, Yale University School of Medicine, New Haven, CT, USA.
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The role of the thalamic nuclei in recognition memory accompanied by recall during encoding and retrieval: An fMRI study. Neuroimage 2013; 74:195-208. [DOI: 10.1016/j.neuroimage.2013.02.017] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2012] [Accepted: 02/02/2013] [Indexed: 11/23/2022] Open
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50
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Jenkins TA. Perinatal complications and schizophrenia: involvement of the immune system. Front Neurosci 2013; 7:110. [PMID: 23805069 PMCID: PMC3691516 DOI: 10.3389/fnins.2013.00110] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2013] [Accepted: 06/01/2013] [Indexed: 11/13/2022] Open
Abstract
The neurodevelopmental hypothesis of schizophrenia suggests that, at least in part, events occurring within the intrauterine or perinatal environment at critical times of brain development underlies emergence of the psychosis observed during adulthood, and brain pathologies that are hypothesized to be from birth. All potential risks stimulate activation of the immune system, and are suggested to act in parallel with an underlying genetic liability, such that an imperfect regulation of the genome mediates these prenatal or early postnatal environmental effects. Epidemiologically based animal models looking at environment and with genes have provided us with a wealth of knowledge in the understanding of the pathophysiology of schizophrenia, and give us the best possibility for interventions and treatments for schizophrenia.
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Affiliation(s)
- Trisha A Jenkins
- School of Medical Sciences, Health Innovations Research Institute, RMIT University Bundoora, VIC, Australia
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