101
|
Rapoport JL, Gogtay N. Childhood onset schizophrenia: support for a progressive neurodevelopmental disorder. Int J Dev Neurosci 2010; 29:251-8. [PMID: 20955775 DOI: 10.1016/j.ijdevneu.2010.10.003] [Citation(s) in RCA: 83] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2010] [Revised: 10/08/2010] [Accepted: 10/11/2010] [Indexed: 10/18/2022] Open
Abstract
Structural brain abnormalities have become an established feature of schizophrenia and increasing evidence points towards the progressive nature of these abnormalities. The brain abnormalities are most profound in early onset cases, which have a severe, treatment refractory phenotype and more salient genetic features. Unique insights could thus be gained in schizophrenia pathology from studying the earliest manifestations of the illness. This paper reviews and updates the findings on anatomic brain development in patients with very early onset schizophrenia while showing preliminary data from ongoing studies. Collectively, our studies demonstrate that childhood-onset schizophrenia (COS) subjects show progressive loss of gray matter, delayed/disrupted white matter (WM) growth, and a progressive decline in cerebellar volume, some of which are shared by their healthy siblings. The developmental patterns or the 'trajectories' of brain development are often more striking than anatomic brain differences at any one point in time; highlighting the importance of longitudinal studies. The sibling findings of partially shared gray matter (GM) deficits which appear to normalize with age, along with other genetic analyses, provide evidence that the brain developmental 'patterns/trajectories' for several regions at particular ages could be useful endophenotypes (trait markers).
Collapse
|
102
|
Abstract
Modeling of human neuropsychiatric disorders in animals is extremely challenging given the subjective nature of many symptoms, the lack of biomarkers and objective diagnostic tests, and the early state of the relevant neurobiology and genetics. Nonetheless, progress in understanding pathophysiology and in treatment development would benefit greatly from improved animal models. Here we review the current state of animal models of mental illness, with a focus on schizophrenia, depression and bipolar disorder. We argue for areas of focus that might increase the likelihood of creating more useful models, at least for some disorders, and for explicit guidelines when animal models are reported.
Collapse
Affiliation(s)
- Eric J Nestler
- Fishberg Department of Neuroscience, Mount Sinai School of Medicine, New York, New York, USA.
| | | |
Collapse
|
103
|
Rosso IM, Makris N, Thermenos HW, Hodge SM, Brown A, Kennedy D, Caviness VS, Faraone SV, Tsuang MT, Seidman LJ. Regional prefrontal cortex gray matter volumes in youth at familial risk for schizophrenia from the Harvard Adolescent High Risk Study. Schizophr Res 2010; 123:15-21. [PMID: 20705433 PMCID: PMC2939267 DOI: 10.1016/j.schres.2010.06.015] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/22/2010] [Revised: 06/16/2010] [Accepted: 06/22/2010] [Indexed: 11/25/2022]
Abstract
BACKGROUND Regional prefrontal cortex gray matter reductions have been identified in schizophrenia, likely reflecting a combination of genetic vulnerability and disease effects. Few morphometric studies to date have examined regional prefrontal abnormalities in non-psychotic biological relatives who have not passed through the age range of peak risk for onset of psychosis. We conducted a region-of-interest morphometric study of prefrontal subregions in adolescent and young adult relatives of schizophrenia patients. METHODS Twenty-seven familial high-risk (FHR) first-degree relatives of schizophrenia patients and forty-eight control subjects without a family history of psychosis (ages 13-28) underwent high-resolution magnetic resonance imaging at 1.5Tesla. The prefrontal cortex was parcellated into polar, dorsolateral, ventrolateral, ventromedial and orbital subregions. The Chapman scales measured subpsychotic symptoms. General linear models examined associations of prefrontal subregion volumes with familial risk and subpsychotic symptoms. RESULTS FHR subjects had significantly reduced bilateral ventromedial prefrontal and frontal pole gray matter volumes compared with controls. Ventromedial volume was significantly negatively correlated with magical ideation and anhedonia scores in FHR subjects. CONCLUSIONS Selective, regional prefrontal gray matter reductions may differentially mark genetic vulnerability and early symptom processes among non-psychotic young adults at familial risk for schizophrenia.
Collapse
Affiliation(s)
- Isabelle M. Rosso
- Department of Psychiatry, Harvard Medical School, Boston, MA,Neuroimaging Center, McLean Hospital, Belmont, MA
| | - Nikos Makris
- Department of Psychiatry, Harvard Medical School, Boston, MA,Center for Morphometric Analysis, Massachusetts General Hospital (MGH), Charlestown, MA,Departments of Neurology and Radiology Services, Harvard Medical School, Boston, MA
| | - Heidi W. Thermenos
- Department of Psychiatry, Harvard Medical School, Boston, MA,Massachusetts Mental Health Center Division of Public Psychiatry, Beth Israel Deaconess Medical Center, Boston, MA,Martinos Center for Biomedical Imaging (Massachusetts Institute of Technology, Harvard Medical School and MGH), Charlestown, MA
| | - Steven M. Hodge
- Center for Morphometric Analysis, Massachusetts General Hospital (MGH), Charlestown, MA
| | - Ariel Brown
- Clinical & Research Program in Pediatric Psychopharmacology, MGH, Boston, MA
| | - David Kennedy
- Center for Morphometric Analysis, Massachusetts General Hospital (MGH), Charlestown, MA,Departments of Neurology and Radiology Services, Harvard Medical School, Boston, MA
| | - Verne S. Caviness
- Center for Morphometric Analysis, Massachusetts General Hospital (MGH), Charlestown, MA,Departments of Neurology and Radiology Services, Harvard Medical School, Boston, MA
| | - Stephen V. Faraone
- Clinical & Research Program in Pediatric Psychopharmacology, MGH, Boston, MA,Departments of Psychiatry and Neuroscience and Physiology, SUNY Upstate Medical University, Syracuse, NY
| | - Ming T. Tsuang
- Department of Psychiatry, Harvard Medical School, Boston, MA,Department of Psychiatry, University of California San Diego, San Diego, CA
| | - Larry J. Seidman
- Department of Psychiatry, Harvard Medical School, Boston, MA,Massachusetts Mental Health Center Division of Public Psychiatry, Beth Israel Deaconess Medical Center, Boston, MA,Martinos Center for Biomedical Imaging (Massachusetts Institute of Technology, Harvard Medical School and MGH), Charlestown, MA,Clinical & Research Program in Pediatric Psychopharmacology, MGH, Boston, MA
| |
Collapse
|
104
|
Gilmore JH, Kang C, Evans DD, Wolfe HM, Smith JK, Lieberman JA, Lin W, Hamer RM, Styner M, Gerig G. Prenatal and neonatal brain structure and white matter maturation in children at high risk for schizophrenia. Am J Psychiatry 2010; 167:1083-91. [PMID: 20516153 PMCID: PMC3105376 DOI: 10.1176/appi.ajp.2010.09101492] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
OBJECTIVE Schizophrenia is a neurodevelopmental disorder associated with abnormalities of brain structure and white matter, although little is known about when these abnormalities arise. This study was conducted to identify structural brain abnormalities in the prenatal and neonatal periods associated with genetic risk for schizophrenia. METHOD Prenatal ultrasound scans and neonatal structural magnetic resonance imaging (MRI) and diffusion tensor imaging were prospectively obtained in the offspring of mothers with schizophrenia or schizoaffective disorder (N=26) and matched comparison mothers without psychiatric illness (N=26). Comparisons were made for prenatal lateral ventricle width and head circumference, for neonatal intracranial, CSF, gray matter, white matter, and lateral ventricle volumes, and for neonatal diffusion properties of the genu and splenium of the corpus callosum and corticospinal tracts. RESULTS Relative to the matched comparison subjects, the offspring of mothers with schizophrenia did not differ in prenatal lateral ventricle width or head circumference. Overall, the high-risk neonates had nonsignificantly larger intracranial, CSF, and lateral ventricle volumes. Subgroup analysis revealed that male high-risk infants had significantly larger intracranial, CSF, total gray matter, and lateral ventricle volumes; the female high-risk neonates were similar to the female comparison subjects. There were no group differences in white matter diffusion tensor properties. CONCLUSIONS Male neonates at genetic risk for schizophrenia had several larger than normal brain volumes, while females did not. To the authors' knowledge, this study provides the first evidence, in the context of its limitations, that early neonatal brain development may be abnormal in males at genetic risk for schizophrenia.
Collapse
|
105
|
Abstract
A pressing need for interrater reliability in the diagnosis of mental disorders emerged during the mid-twentieth century, prompted in part by the development of diverse new treatments. The Diagnostic and Statistical Manual of Mental Disorders (DSM), third edition answered this need by introducing operationalized diagnostic criteria that were field-tested for interrater reliability. Unfortunately, the focus on reliability came at a time when the scientific understanding of mental disorders was embryonic and could not yield valid disease definitions. Based on accreting problems with the current DSM-fourth edition (DSM-IV) classification, it is apparent that validity will not be achieved simply by refining criteria for existing disorders or by the addition of new disorders. Yet DSM-IV diagnostic criteria dominate thinking about mental disorders in clinical practice, research, treatment development, and law. As a result, the modern DSM system, intended to create a shared language, also creates epistemic blinders that impede progress toward valid diagnoses. Insights that are beginning to emerge from psychology, neuroscience, and genetics suggest possible strategies for moving forward.
Collapse
Affiliation(s)
- Steven E Hyman
- Department of Neurobiology, Harvard Medical School, Harvard University, Cambridge, Massachusetts 02138, USA.
| |
Collapse
|
106
|
Abstract
Working memory performance is significantly influenced by genetic factors. Here, we assessed genetic contributions to both working memory performance and neuroimaging measures focused on the network of brain regions associated with working memory by using a sample of 467 human participants from extended families. Imaging measures included diffusion tensor imaging indices in major white matter tracts thought to be associated with working memory and structural magnetic resonance imaging measures of frontal and parietal gray matter density. Analyses directly addressed whether working memory performance and neural structural integrity are influenced by common genetic factors (e.g., pleiotropy). While all cognitive measures, gray matter regions, and white matter tracts assessed were heritable, only performance on a spatial delayed response task and integrity of the superior longitudinal fasciculus (a primary fronto-parietal connection) shared genetic factors. As working memory may be a core component of other higher level processes, such as general intelligence, this finding has implications for the heritability of complex cognitive functions, as well as for our understanding of the transmission of cognitive deficits in mental and neurological disorders.
Collapse
|
107
|
Ide M, Lewis DA. Altered cortical CDC42 signaling pathways in schizophrenia: implications for dendritic spine deficits. Biol Psychiatry 2010; 68:25-32. [PMID: 20385374 PMCID: PMC2900524 DOI: 10.1016/j.biopsych.2010.02.016] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/19/2010] [Revised: 02/18/2010] [Accepted: 02/23/2010] [Indexed: 10/19/2022]
Abstract
BACKGROUND Spine density on the basilar dendrites of pyramidal neurons is lower in layer 3, but not in layers 5 and 6, in the dorsolateral prefrontal cortex (DLPFC) of subjects with schizophrenia. The expression of CDC42 (cell division cycle 42), a RhoGTPase that regulates the outgrowth of the actin cytoskeleton and promotes spine formation, is also lower in schizophrenia; however, CDC42 mRNA is lower across layers 3-6, suggesting that other lamina-specific molecular alterations are critical for the spine deficits in the illness. The CDC42 effector proteins 3 and 4 (CDC42EP3, CDC42EP4) are preferentially expressed in DLPFC layers 2 and 3, and CDC42EP3 appears to assemble septin filaments in spine necks. Therefore, alterations in CDC42EP3 could contribute to the lamina-specific spine deficits in schizophrenia. METHODS We measured transcript levels of CDC42, CDC42EP3, CDC42EP4; their interacting proteins (septins [SEPT2, 3, 5, 6, 7, 8, and 11], anillin), and other spine-specific proteins (spinophilin, PSD-95, and synaptopodin) in the DLPFC from 31 subjects with schizophrenia and matched normal comparison subjects. RESULTS The expression of CDC42EP3 mRNA was significantly increased by 19.7%, and SEPT7 mRNA was significantly decreased by 6.9% in subjects with schizophrenia. Cortical levels of CDC42EP3 and SEPT7 mRNAs were not altered in monkeys chronically exposed to antipsychotic medications. CONCLUSIONS Activated CDC42 is thought to disrupt septin filaments transiently in spine necks, allowing the molecular translocations required for synaptic potentiation. Thus, altered CDC42 signaling via CDC42EP3 may perturb synaptic plasticity and contribute to the spine deficits observed in layer 3 pyramidal neurons in schizophrenia.
Collapse
|
108
|
Short SJ, Lubach GR, Karasin AI, Olsen CW, Styner M, Knickmeyer RC, Gilmore JH, Coe CL. Maternal influenza infection during pregnancy impacts postnatal brain development in the rhesus monkey. Biol Psychiatry 2010; 67:965-73. [PMID: 20079486 PMCID: PMC3235476 DOI: 10.1016/j.biopsych.2009.11.026] [Citation(s) in RCA: 142] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2009] [Revised: 11/23/2009] [Accepted: 11/24/2009] [Indexed: 01/22/2023]
Abstract
BACKGROUND Maternal infection with influenza and other pathogens during pregnancy has been associated with increased risk for schizophrenia and neurodevelopmental disorders. In rodent studies, maternal inflammatory responses to influenza affect fetal brain development. However, to verify the relevance of these findings to humans, research is needed in a primate species with more advanced prenatal corticogenesis. METHODS Twelve pregnant rhesus monkeys were infected with influenza, A/Sydney/5/97 (H3N2), 1 month before term (early third trimester) and compared with 7 control pregnancies. Nasal swabs and blood samples confirmed viral shedding and immune activation. Structural magnetic resonance imaging was conducted at 1 year; behavioral development and cortisol reactivity were also assessed. RESULTS Maternal infections were mild and self-limiting. At birth, maternally derived influenza-specific immunoglobulin G was present in the neonate, but there was no evidence of direct viral exposure. Birth weight and gestation length were not affected, nor were infant neuromotor, behavioral, and endocrine responses. However, magnetic resonance imaging analyses revealed significant reductions in cortical gray matter in flu-exposed animals. Regional analyses indicated the largest gray matter reductions occurred bilaterally in cingulate and parietal areas; white matter was also reduced significantly in the parietal lobe. CONCLUSIONS Influenza infection during pregnancy affects neural development in the monkey, reducing gray matter throughout most of the cortex and decreasing white matter in parietal cortex. These brain alterations are likely to be permanent, given that they were still present at the monkey-equivalent of older childhood and thus might increase the likelihood of later behavioral pathology.
Collapse
Affiliation(s)
- Sarah J Short
- Department of Psychology, Harlow Center for Biological Psychology, University of Wisconsin, Madison, Wisconsin, USA.
| | | | | | | | | | | | | | | |
Collapse
|
109
|
Borgwardt SJ, Picchioni MM, Ettinger U, Toulopoulou T, Murray R, McGuire PK. Regional gray matter volume in monozygotic twins concordant and discordant for schizophrenia. Biol Psychiatry 2010; 67:956-64. [PMID: 20006324 DOI: 10.1016/j.biopsych.2009.10.026] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/02/2009] [Revised: 10/08/2009] [Accepted: 10/11/2009] [Indexed: 10/20/2022]
Abstract
BACKGROUND Alterations in gray matter volume (GMV) are a robust feature of schizophrenia. However, it is not clear to what extent these abnormalities are correlates of the genetic liability to the disorder, as opposed to environmental factors and the disorder itself. We investigated the influence of genetic and environmental risk on GMV in monozygotic (MZ) twin pairs concordant and discordant for schizophrenia. METHODS Total and regional GMVs were measured from magnetic resonance images of 80 twins: 14 MZ pairs concordant for schizophrenia, 9 pairs discordant for schizophrenia, and 17 healthy MZ twin pairs. RESULTS Total GMV was smaller in twins with schizophrenia (t = -3.17, p = .003) and nonpsychotic cotwins from discordant pairs (t = -2.66, p = .011) than in healthy control twins. Twin pairs concordant for schizophrenia displayed reduced regional GMV in the inferior frontal, medial frontal, and anterior cingulate gyri; the caudate; lingual gyrus; and cerebellum relative to healthy twins (p < .05, corrected). Within discordant pairs, twins with schizophrenia had less GMV than their nonpsychotic cotwins in the insula; superior/medial frontal, pre/postcentral, cingulate, and superior temporal gyri; and the paracentral lobule. There were no significant differences in regional GMV between nonpsychotic cotwins and healthy control subjects. CONCLUSIONS The presence of schizophrenia was specifically related to reduced GMV in frontal, insular, cingulate, medial parietal, and temporal cortex, over and above effects of genetic risk for the disorder. These changes could be related to the pathophysiology of the disorder itself or to unique environmental factors acting etiologically or because of the illness.
Collapse
Affiliation(s)
- Stefan J Borgwardt
- Section of Neuroimaging, Institute of Psychiatry, King's College London, London, United Kingdom.
| | | | | | | | | | | |
Collapse
|
110
|
Ivleva EI, Morris DW, Moates AF, Suppes T, Thaker GK, Tamminga CA. Genetics and intermediate phenotypes of the schizophrenia--bipolar disorder boundary. Neurosci Biobehav Rev 2010; 34:897-921. [PMID: 19954751 DOI: 10.1016/j.neubiorev.2009.11.022] [Citation(s) in RCA: 115] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2009] [Revised: 11/20/2009] [Accepted: 11/23/2009] [Indexed: 12/20/2022]
Abstract
Categorization of psychotic illnesses into schizophrenic and affective psychoses remains an ongoing controversy. Although Kraepelinian subtyping of psychosis was historically beneficial, modern genetic and neurophysiological studies do not support dichotomous conceptualization of psychosis. Evidence suggests that schizophrenia and bipolar disorder rather present a clinical continuum with partially overlapping symptom dimensions, neurophysiology, genetics and treatment responses. Recent large scale genetic studies have produced inconsistent findings and exposed an urgent need for re-thinking phenomenology-based approach in psychiatric research. Epidemiological, linkage and molecular genetic studies, as well as studies in intermediate phenotypes (neurocognitive, neurophysiological and anatomical imaging) in schizophrenia and bipolar disorders are reviewed in order to support a dimensional conceptualization of psychosis. Overlapping and unique genetic and intermediate phenotypic signatures of the two psychoses are comprehensively recapitulated. Alternative strategies which may be implicated into genetic research are discussed.
Collapse
Affiliation(s)
- Elena I Ivleva
- Department of Psychiatry, UT Southwestern Medical Center, Dallas, TX 75235, USA.
| | | | | | | | | | | |
Collapse
|
111
|
Harms MP, Wang L, Campanella C, Aldridge K, Moffitt AJ, Kuelper J, Ratnanather JT, Miller MI, Barch DM, Csernansky JG. Structural abnormalities in gyri of the prefrontal cortex in individuals with schizophrenia and their unaffected siblings. Br J Psychiatry 2010; 196:150-7. [PMID: 20118463 PMCID: PMC2815937 DOI: 10.1192/bjp.bp.109.067314] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
BACKGROUND The relatives of individuals with schizophrenia exhibit deficits of overall frontal lobe volume, consistent with a genetic contribution to these deficits. AIMS To quantify the structure of gyral-defined subregions of prefrontal cortex in individuals with schizophrenia and their siblings. METHOD Grey matter volume, cortical thickness, and surface area of the superior, middle and inferior frontal gyri were measured in participants with schizophrenia and their unaffected (non-psychotic) siblings (n = 26 pairs), and controls and their siblings (n = 40 pairs). RESULTS Grey matter volume was reduced in the middle and inferior frontal gyri of individuals with schizophrenia, relative to controls. However, only inferior frontal gyrus volume was also reduced in the unaffected siblings of those with schizophrenia, yielding a volume intermediate between their affected siblings and controls. CONCLUSIONS The structure of subregions of the prefrontal cortex may be differentially influenced by genetic factors in schizophrenia, with inferior frontal gyrus volume being most related to familial risk.
Collapse
|
112
|
Gogtay N, Thompson PM. Mapping gray matter development: implications for typical development and vulnerability to psychopathology. Brain Cogn 2010; 72:6-15. [PMID: 19796863 PMCID: PMC2815268 DOI: 10.1016/j.bandc.2009.08.009] [Citation(s) in RCA: 224] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Recent studies with brain magnetic resonance imaging (MRI) have scanned large numbers of children and adolescents repeatedly over time, as their brains develop, tracking volumetric changes in gray and white matter in remarkable detail. Focusing on gray matter changes specifically, here we explain how earlier studies using lobar volumes of specific anatomical regions showed how different lobes of the brain matured at different rates. With the advent of more sophisticated brain mapping methods, it became possible to chart the dynamic trajectory of cortical maturation using detailed 3D and 4D (dynamic) models, showing spreading waves of changes evolving through the cortex. This led to a variety of time-lapse films revealing characteristic deviations from normal development in schizophrenia, bipolar illness, and even in siblings at genetic risk for these disorders. We describe how these methods have helped clarify how cortical development relates to cognitive performance, functional recovery or decline in illness, and ongoing myelination processes. These time-lapse maps have also been used to study effects of genotype and medication on cortical maturation, presenting a powerful framework to study factors that influence the developing brain.
Collapse
Affiliation(s)
- Nitin Gogtay
- Child Psychiatry Branch, NIMH, NIH, Building 10, Rm 3N202, 10 Center Drive, MSC-1600, Bethesda, MD 20892, USA.
| | | |
Collapse
|
113
|
Narr KL, Szeszko PR, Lencz T, Woods RP, Hamilton LS, Phillips O, Robinson D, Burdick KE, DeRosse P, Kucherlapati R, Thompson PM, Toga AW, Malhotra AK, Bilder RM. DTNBP1 is associated with imaging phenotypes in schizophrenia. Hum Brain Mapp 2010; 30:3783-94. [PMID: 19449336 DOI: 10.1002/hbm.20806] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Dystrobrevin binding protein 1 (DTNBP1) has been identified as putative schizophrenia susceptibility gene, but it remains unknown whether polymorphisms relate to altered cerebral structure. We examined relationships between a previously implicated DTNBP1 risk variant [P1578] and global and segmented brain tissue volumes and regional cortical thickness in schizophrenia (n = 62; 24 risk carriers) and healthy subjects (n = 42; 11 risk carriers), across ethnic groups and within Caucasians. Schizophrenia patients showed similar brain volumes, but significantly reduced brain-size adjusted gray matter and CSF volumes and cortical thinning in a widespread neocortical distribution compared to controls. DTNBP1 risk was found associated with reduced brain volume, but not with tissue sub-compartments. Cortical thickness, which was weakly associated with brain size, showed regional variations in association with genetic risk, although effects were dominated by highly significant genotype by diagnosis interactions over broad areas of cortex. Risk status was found associated with regional cortical thinning in patients, particularly in temporal networks, but with thickness increases in controls. DTNBP1 effects for brain volume and cortical thickness appear driven by different neurobiological processes. Smaller brain volumes observed in risk carriers may relate to previously reported DTNBP1/cognitive function relationships irrespective of diagnosis. Regional cortical thinning in patient, but not in control risk carriers, may suggest that DTNBP1 interacts with other schizophrenia-related risk factors to affect laminar thickness. Alternatively, DTNBP1 may influence neural processes for which individuals with thicker cortex are less vulnerable. Although DTNBP1 relates to cortical thinning in schizophrenia, morphological changes in the disorder are influenced by additional genetic and/or environmental factors.
Collapse
Affiliation(s)
- Katherine L Narr
- Laboratory of Neuro Imaging and Ahmanson-Lovelace Brain Mapping Center, Department of Neurology, Geffen School of Medicine at UCLA, Los Angeles, California 90095, USA.
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
114
|
Abstract
After decades of research aimed at elucidating the pathophysiology and etiology of schizophrenia, it has become increasingly apparent that it is an illness knowing few boundaries. Psychopathological manifestations extend across several domains, impacting multiple facets of real-world functioning for the affected individual. Even within one such domain, arguably the most enduring, difficult to treat, and devastating to long-term functioning-executive impairment-there are not only a host of disrupted component processes, but also a complex underlying dysfunctional neural architecture. Further, just as implicated brain structures (eg, dorsolateral prefrontal cortex) through postmortem and neuroimaging techniques continue to show alterations in multiple, interacting signaling pathways, so too does evolving understanding of genetic risk factors suggest multiple molecular entry points to illness liability. With this expansive network of interactions in mind, the present chapter takes a systems-level approach to executive dysfunction in schizophrenia, by identifying key regions both within and outside of the frontal lobes that show changes in schizophrenia and are important in cognitive control neural circuitry, summarizing current knowledge of their relevant functional interactions, and reviewing emerging links between schizophrenia risk genetics and characteristic executive circuit aberrancies observed with neuroimaging methods.
Collapse
|
115
|
Brain surface contraction mapped in first-episode schizophrenia: a longitudinal magnetic resonance imaging study. Mol Psychiatry 2009; 14:976-86. [PMID: 18607377 PMCID: PMC2773126 DOI: 10.1038/mp.2008.34] [Citation(s) in RCA: 114] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Schizophrenia is associated with structural brain abnormalities, but the timing of onset and course of these changes remains unclear. Longitudinal magnetic resonance imaging (MRI) studies have demonstrated progressive brain volume decreases in patients around and after the onset of illness, although considerable discrepancies exist regarding which brain regions are affected. The anatomical pattern of these progressive changes in schizophrenia is largely unknown. In this study, MRI scans were acquired repeatedly from 16 schizophrenia patients approximately 2 years apart following their first episode of illness, and also from 14 age-matched healthy subjects. Cortical Pattern Matching, in combination with Structural Image Evaluation, using Normalisation, of Atrophy, was applied to compare the rates of cortical surface contraction between patients and controls. Surface contraction in the dorsal surfaces of the frontal lobe was significantly greater in patients with first-episode schizophrenia (FESZ) compared with healthy controls. Overall, brain surface contraction in patients and healthy controls showed similar anatomical patterns, with that of the former group exaggerated in magnitude across the entire brain surface. That the pattern of structural change in the early course of schizophrenia corresponds so closely to that associated with normal development is consistent with the hypothesis that a schizophrenia-related factor interacts with normal adolescent brain developmental processes in the pathophysiology of schizophrenia. The exaggerated progressive changes seen in patients with schizophrenia may reflect an increased rate of synaptic pruning, resulting in excessive loss of neuronal connectivity, as predicted by the late neurodevelopmental hypothesis of the illness.
Collapse
|
116
|
de Krom M, Bauer F, Collier D, Adan RAH, la Fleur SE. Genetic variation and effects on human eating behavior. Annu Rev Nutr 2009; 29:283-304. [PMID: 19400703 DOI: 10.1146/annurev-nutr-080508-141124] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Feeding is a physiological process, influenced by genetic factors and the environment. In recent years, many studies have been performed to unravel the involvement of genetics in both eating behavior and its pathological forms: eating disorders and obesity. In this review, we provide a condensed introduction on the neurological aspects of eating and we describe the current status of research into the genetics of eating behavior, primarily focused on specific traits such as taste, satiation, and hunger. This is followed by an overview on the genetic studies done to unravel the heritable background of obesity and eating disorders. We examine the discussion currently taking place in the field of genetics of complex disorders and phenotypes on how to perform good and powerful studies, with the use of large-scale whole-genome association studies as one of the possible solutions. In the final part of this review, we give our view on the latest developments, including endophenotype approaches and animal studies. Studies of endophenotypes of eating behavior may help to identify core traits that are genetically influenced. Such studies would yield important knowledge on the underlying biological scaffold on which diagnostic criteria for eating disorders could be based and would provide information to influence eating behavior toward healthier living.
Collapse
Affiliation(s)
- Mariken de Krom
- Rudolf Magnus Institute of Neuroscience, Department of Neuroscience & Pharmacology, UMC Utrecht, Utrecht, The Netherlands.
| | | | | | | | | |
Collapse
|
117
|
Peters BD, Schmitz N, Dingemans PM, van Amelsvoort TA, Linszen DH, de Haan L, Majoie CB, den Heeten GJ. Preliminary evidence for reduced frontal white matter integrity in subjects at ultra-high-risk for psychosis. Schizophr Res 2009; 111:192-3. [PMID: 19372031 DOI: 10.1016/j.schres.2009.03.018] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/05/2008] [Revised: 03/09/2009] [Accepted: 03/09/2009] [Indexed: 11/26/2022]
|
118
|
Brun CC, Leporé N, Pennec X, Lee AD, Barysheva M, Madsen SK, Avedissian C, Chou YY, de Zubicaray GI, McMahon KL, Wright MJ, Toga AW, Thompson PM. Mapping the regional influence of genetics on brain structure variability--a tensor-based morphometry study. Neuroimage 2009; 48:37-49. [PMID: 19446645 DOI: 10.1016/j.neuroimage.2009.05.022] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2008] [Revised: 05/04/2009] [Accepted: 05/05/2009] [Indexed: 11/29/2022] Open
Abstract
Genetic and environmental factors influence brain structure and function profoundly. The search for heritable anatomical features and their influencing genes would be accelerated with detailed 3D maps showing the degree to which brain morphometry is genetically determined. As part of an MRI study that will scan 1150 twins, we applied Tensor-Based Morphometry to compute morphometric differences in 23 pairs of identical twins and 23 pairs of same-sex fraternal twins (mean age: 23.8+/-1.8 SD years). All 92 twins' 3D brain MRI scans were nonlinearly registered to a common space using a Riemannian fluid-based warping approach to compute volumetric differences across subjects. A multi-template method was used to improve volume quantification. Vector fields driving each subject's anatomy onto the common template were analyzed to create maps of local volumetric excesses and deficits relative to the standard template. Using a new structural equation modeling method, we computed the voxelwise proportion of variance in volumes attributable to additive (A) or dominant (D) genetic factors versus shared environmental (C) or unique environmental factors (E). The method was also applied to various anatomical regions of interest (ROIs). As hypothesized, the overall volumes of the brain, basal ganglia, thalamus, and each lobe were under strong genetic control; local white matter volumes were mostly controlled by common environment. After adjusting for individual differences in overall brain scale, genetic influences were still relatively high in the corpus callosum and in early-maturing brain regions such as the occipital lobes, while environmental influences were greater in frontal brain regions that have a more protracted maturational time-course.
Collapse
Affiliation(s)
- Caroline C Brun
- Laboratory of Neuro Imaging, Department of Neurology, UCLA School of Medicine, 635 Charles Young Drive South Suite 225, Los Angeles, CA 90095-7334, USA
| | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
119
|
Abnormal prefrontal cortical activity and connectivity during response selection in first episode psychosis, chronic schizophrenia, and unaffected siblings of individuals with schizophrenia. Schizophr Res 2009; 109:182-90. [PMID: 19179050 DOI: 10.1016/j.schres.2008.11.028] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/09/2008] [Revised: 11/23/2008] [Accepted: 11/25/2008] [Indexed: 11/23/2022]
Abstract
The search for genes conferring liability for schizophrenia may be aided by the identification of endophenotypes. Response selection is a heritable cognitive function that is impaired in patients with schizophrenia and their unaffected siblings. The abnormalities in cerebral function that presumably underlie the deficit in patients and unaffected siblings remain to be elucidated. Cerebral neurophysiology during performance of a 4-choice reaction time (CRT) task in 25 patients with schizophrenia (15 medication free first episode (FEP) and 10 chronic patients), 32 controls, and 12 unaffected siblings of individuals with schizophrenia was investigated using fMRI. CRT was impaired in both medication free FEP and chronic patients with schizophrenia, and unaffected siblings. FEP patients, chronic patients, and unaffected siblings demonstrated greater BOLD response in the right dorsolateral prefrontal cortex (dlPFC) during CRT task blocks. The nature of the altered activation in the dlPFC was further examined using functional connectivity analysis. This revealed marked reductions in connectivity between the right dlPFC and multiple brain regions in both patient groups and, to a lesser degree, unaffected siblings. The magnitude of connectivity between right dlPFC and inferior parietal lobule correlated with task performance in the combined patient/unaffected siblings group, but not controls suggesting that the network of brain regions recruited to perform the task differed as a function of genetic liability for schizophrenia. The findings suggest that altered activity and connectivity of the right dlPFC appears to be related to genetic vulnerability for schizophrenia and may represent a potential endophenotype of the disorder.
Collapse
|
120
|
Takahashi T, Kosaka H, Murata T, Omori M, Narita K, Mitsuya H, Takahashi K, Kimura H, Wada Y. Application of a multifractal analysis to study brain white matter abnormalities of schizophrenia on T2-weighted magnetic resonance imaging. Psychiatry Res 2009; 171:177-88. [PMID: 19217265 DOI: 10.1016/j.pscychresns.2008.03.009] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/18/2007] [Revised: 02/08/2008] [Accepted: 03/26/2008] [Indexed: 11/29/2022]
Abstract
Multifractal analysis provides a precise quantitative description of the structural complexity of white matter (WM) on magnetic resonance imaging (MRI). To test this new technique as an aid to elucidating the pathology of schizophrenia, we examined a multifractal dimension (i.e. Deltaalpha) of WM in schizophrenia patients and their relations to clinical variables. We examined 16 patients with schizophrenia and 16 controls matched for age, sex and handedness. Delta alpha value of WM in the prefrontal and frontoparietal lobes and the corpus callosum (genu and splenium) on T2-weighted MRI was calculated. Delta alpha was not significantly different between groups in either region of interest. However, group-by-side interaction for Deltaalpha was found in the frontoparietal WM; post-hoc analysis revealed normal left dominant asymmetry in Deltaalpha for frontoparietal WM in control subjects, which was absent in schizophrenia patients. Furthermore, the patients with schizophrenia had a lower asymmetry coefficient ([R-L]/[R+L]) for Deltaalpha in frontoparietal WM. Relations to clinical symptoms from the Positive and Negative Syndrome Scale, Deltaalpha in corpus callosum, and the asymmetry coefficient in prefrontal WM were correlated with negative and general psychopathology symptom scores. Our results support the left-sided dysfunction hypothesis of schizophrenia and its relation to schizophrenic symptoms. Multifractal analysis reveals abnormal patterns of WM structures in schizophrenia that could be implicated in the disorder's etiology.
Collapse
Affiliation(s)
- Tetsuya Takahashi
- Department of Neuropsychiatry, Faculty of Medical Sciences, University of Fukui, Fukui, Japan
| | | | | | | | | | | | | | | | | |
Collapse
|
121
|
Progressive brain structural changes mapped as psychosis develops in 'at risk' individuals. Schizophr Res 2009; 108:85-92. [PMID: 19138834 PMCID: PMC2670732 DOI: 10.1016/j.schres.2008.11.026] [Citation(s) in RCA: 219] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/13/2008] [Revised: 11/20/2008] [Accepted: 11/21/2008] [Indexed: 12/21/2022]
Abstract
BACKGROUND Schizophrenia and related psychoses are associated with brain structural abnormalities. Recent findings in 'at risk' populations have identified progressive changes in various brain regions preceding illness onset, while changes especially in prefrontal and superior temporal regions have been demonstrated in first-episode schizophrenia patients. However, the timing of the cortical changes and their regional extent, relative to the emergence of psychosis, has not been clarified. We followed individuals at high-risk for psychosis to determine whether structural changes in the cerebral cortex occur with the onset of psychosis. We hypothesized that progressive volume loss occurs in prefrontal regions during the transition to psychosis. METHODS 35 individuals at ultra-high risk (UHR) for developing psychosis, of whom 12 experienced psychotic onset by 1-year follow-up ('converters'), participated in a longitudinal structural MRI study. Baseline and follow-up T1-weighted MR images were acquired and longitudinal brain surface contractions were assessed using Cortical Pattern Matching. RESULTS Significantly greater brain contraction was found in the right prefrontal region in the 'converters' compared with UHR cases who did not develop psychosis ('non-converters'). CONCLUSIONS These findings show cortical volume loss is associated with the onset of psychosis, indicating ongoing pathological processes during the transition stage to illness. The prefrontal volume loss is in line with structural and functional abnormalities in schizophrenia, suggesting a critical role for this change in the development of psychosis.
Collapse
|
122
|
Neuroanatomical differences between familial and sporadic schizophrenia and their parents: an optimized voxel-based morphometry study. Psychiatry Res 2009; 171:71-81. [PMID: 19168334 DOI: 10.1016/j.pscychresns.2008.02.004] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/08/2007] [Revised: 01/24/2008] [Accepted: 02/13/2008] [Indexed: 02/05/2023]
Abstract
Symptomatic differences have been reported between patients with familial and sporadic schizophrenia. The present study examined neuroanatomical differences between the two subgroups and their parents using voxel-based morphometry. High-resolution T1-weighted images were obtained using 3 Tesla magnetic resonance imaging from 20 patients with schizophrenia (familial subgroup, n=10; sporadic subgroup, n=10), 20 of their parents (familial subgroup, n=10; sporadic subgroup, n=10) and 20 healthy volunteers. Gray matter density (GMD) was compared between groups on a voxel-by-voxel basis. Compared with the sporadic patients, the familial patients had significantly reduced GMD in the thalamus bilaterally. Reduction of GMD in bilateral thalami was also found in familial parents in comparison with sporadic parents. Compared with controls, both familial and sporadic patients had lower GMD involving bilateral insula, right temporal lobe, right occipital lobe, left lenticular nucleus and right cerebellum. However, only familial patients showed lower GMD than controls in the right thalamus. Compared with controls, only familial parents showed lower GMD in the right insula extending to the right temporal lobe and the right parietal lobule. The present data suggest that familial schizophrenia is associated with more severe structural abnormalities than sporadic schizophrenia, especially in the thalamus.
Collapse
|
123
|
Chou YY, Leporé N, Chiang MC, Avedissian C, Barysheva M, McMahon KL, de Zubicaray GI, Meredith M, Wright MJ, Toga AW, Thompson PM. Mapping genetic influences on ventricular structure in twins. Neuroimage 2009; 44:1312-23. [PMID: 19041405 PMCID: PMC2773138 DOI: 10.1016/j.neuroimage.2008.10.036] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2008] [Revised: 10/15/2008] [Accepted: 10/21/2008] [Indexed: 11/16/2022] Open
Abstract
Despite substantial progress in measuring the anatomical and functional variability of the human brain, little is known about the genetic and environmental causes of these variations. Here we developed an automated system to visualize genetic and environmental effects on brain structure in large brain MRI databases. We applied our multi-template segmentation approach termed "Multi-Atlas Fluid Image Alignment" to fluidly propagate hand-labeled parameterized surface meshes, labeling the lateral ventricles, in 3D volumetric MRI scans of 76 identical (monozygotic, MZ) twins (38 pairs; mean age=24.6 (SD=1.7)); and 56 same-sex fraternal (dizygotic, DZ) twins (28 pairs; mean age=23.0 (SD=1.8)), scanned as part of a 5-year research study that will eventually study over 1000 subjects. Mesh surfaces were averaged within subjects to minimize segmentation error. We fitted quantitative genetic models at each of 30,000 surface points to measure the proportion of shape variance attributable to (1) genetic differences among subjects, (2) environmental influences unique to each individual, and (3) shared environmental effects. Surface-based statistical maps, derived from path analysis, revealed patterns of heritability, and their significance, in 3D. Path coefficients for the 'ACE' model that best fitted the data indicated significant contributions from genetic factors (A=7.3%), common environment (C=38.9%) and unique environment (E=53.8%) to lateral ventricular volume. Earlier-maturing occipital horn regions may also be more genetically influenced than later-maturing frontal regions. Maps visualized spatially-varying profiles of environmental versus genetic influences. The approach shows promise for automatically measuring gene-environment effects in large image databases.
Collapse
Affiliation(s)
- Yi-Yu Chou
- Department of Neurology, UCLA School of Medicine, Laboratory of Neuro Imaging, Los Angeles, CA 90095-7332, USA
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
124
|
Reig S, Moreno C, Moreno D, Burdalo M, Janssen J, Parellada M, Zabala A, Desco M, Arango C. Progression of brain volume changes in adolescent-onset psychosis. Schizophr Bull 2009; 35:233-43. [PMID: 18222929 PMCID: PMC2643965 DOI: 10.1093/schbul/sbm160] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Little is known about the changes that take place in the adolescent brain over the first few years following the onset of psychosis. The present longitudinal study builds on an earlier cross-sectional report demonstrating brain abnormalities in adolescent-onset psychosis patients with a recent-onset first episode of psychosis. Magnetic resonance imaging studies were obtained at baseline and 2 years later from 21 adolescents with psychosis and 34 healthy controls matched for age, gender, and years of education. Whole-brain volumes and gray matter (GM) and cerebrospinal fluid (CSF) volumes of the frontal, parietal, temporal, and occipital lobes were measured at baseline and at 2-year follow-up. In the frontal lobe, the rate of GM volume loss was significantly higher in male patients (2.9% and 2.0%, respectively, for left and right) than in controls (1.2% and 0.7%, respectively, for left and right). In the left frontal lobe, male patients showed a significantly higher rate of CSF volume increase than controls (8.6% vs 6.4%). These differences in rates of volume change were observed in male and female patients, although only males showed significant time x diagnosis interactions. This negative finding in females should be interpreted with caution as the study was underpowered to detect change in women due to limited sample size. An exploratory analysis revealed that schizophrenia and nonschizophrenia psychotic disorders showed similar volume change patterns relative to controls. Change in clinical status was not correlated with longitudinal brain changes. Our results support progression of frontal lobe changes in males with adolescent-onset psychosis.
Collapse
Affiliation(s)
| | - Carmen Moreno
- Adolescent Unit, Department of Psychiatry, Hospital General Universitario Gregorio Marañón, Madrid, Spain
| | - Dolores Moreno
- Adolescent Unit, Department of Psychiatry, Hospital General Universitario Gregorio Marañón, Madrid, Spain
| | - Maite Burdalo
- Adolescent Unit, Department of Psychiatry, Hospital General Universitario Gregorio Marañón, Madrid, Spain
| | - Joost Janssen
- Department of Experimental Medicine,Adolescent Unit, Department of Psychiatry, Hospital General Universitario Gregorio Marañón, Madrid, Spain
| | - Mara Parellada
- Adolescent Unit, Department of Psychiatry, Hospital General Universitario Gregorio Marañón, Madrid, Spain
| | - Arantzazu Zabala
- Adolescent Unit, Department of Psychiatry, Hospital General Universitario Gregorio Marañón, Madrid, Spain
| | | | - Celso Arango
- Adolescent Unit, Department of Psychiatry, Hospital General Universitario Gregorio Marañón, Madrid, Spain,To whom correspondence should be addressed; Adolescent Unit, Department of Psychiatry, Hospital General Universitario Gregorio Marañón, Dr Esquerdo 46, Madrid 28007, Spain; tel: 34-914265057, fax: 34-914265108, e-mail:
| |
Collapse
|
125
|
Kaymaz N, van Os J. Heritability of Structural Brain Traits. NOVEL APPROACHES TO STUDYING BASAL GANGLIA AND RELATED NEUROPSYCHIATRIC DISORDERS 2009; 89:85-130. [DOI: 10.1016/s0074-7742(09)89005-3] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
|
126
|
Potkin SG, Turner JA, Brown GG, McCarthy G, Greve DN, Glover GH, Manoach DS, Belger A, Diaz M, Wible CG, Ford JM, Mathalon DH, Gollub R, Lauriello J, O'Leary D, van Erp TGM, Toga AW, Preda A, Lim KO. Working memory and DLPFC inefficiency in schizophrenia: the FBIRN study. Schizophr Bull 2009; 35:19-31. [PMID: 19042912 PMCID: PMC2643959 DOI: 10.1093/schbul/sbn162] [Citation(s) in RCA: 256] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
BACKGROUND The Functional Imaging Biomedical Informatics Network is a consortium developing methods for multisite functional imaging studies. Both prefrontal hyper- or hypoactivity in chronic schizophrenia have been found in previous studies of working memory. METHODS In this functional magnetic resonance imaging (fMRI) study of working memory, 128 subjects with chronic schizophrenia and 128 age- and gender-matched controls were recruited from 10 universities around the United States. Subjects performed the Sternberg Item Recognition Paradigm1,2 with memory loads of 1, 3, or 5 items. A region of interest analysis examined the mean BOLD signal change in an atlas-based demarcation of the dorsolateral prefrontal cortex (DLPFC), in both groups, during both the encoding and retrieval phases of the experiment over the various memory loads. RESULTS Subjects with schizophrenia performed slightly but significantly worse than the healthy volunteers and showed a greater decrease in accuracy and increase in reaction time with increasing memory load. The mean BOLD signal in the DLPFC was significantly greater in the schizophrenic group than the healthy group, particularly in the intermediate load condition. A secondary analysis matched subjects for mean accuracy and found the same BOLD signal hyperresponse in schizophrenics. CONCLUSIONS The increase in BOLD signal change from minimal to moderate memory loads was greater in the schizophrenic subjects than in controls. This effect remained when age, gender, run, hemisphere, and performance were considered, consistent with inefficient DLPFC function during working memory. These findings from a large multisite sample support the concept not of hyper- or hypofrontality in schizophrenia, but rather DLPFC inefficiency that may be manifested in either direction depending on task demands. This redirects the focus of research from direction of difference to neural mechanisms of inefficiency.
Collapse
Affiliation(s)
- S. G. Potkin
- Department of Psychiatry and Human Behavior, University of California Irvine, Irvine, CA 92697,To whom correspondence should be addressed; Department of Psychiatry and Human Behavior, University of California, Irvine, 5251 California Avenue, Suite 240, Irvine, CA 92617; tel: 949-824-8040, fax: 949-824-3324, e-mail:
| | - J. A. Turner
- Department of Psychiatry and Human Behavior, University of California Irvine, Irvine, CA 92697
| | - G. G. Brown
- Department of Psychiatry, University of California San Diego, San Diego, CA 92161
| | - G. McCarthy
- Department of Psychiatry, Yale University, New Haven, CT 06520
| | - D. N. Greve
- Neuroimaging Division, Department of Psychiatry, Massachusetts General Hospital, Charlestown, MA 02129
| | - G. H. Glover
- Lucas Imaging Center, Stanford University, Palo Alto, CA
| | - D. S. Manoach
- Neuroimaging Division, Department of Psychiatry, Massachusetts General Hospital, Charlestown, MA 02129
| | - A. Belger
- University of North Carolina, Chapel Hill, NC,Brain Imaging and Analysis Center, Duke University Medical Center, Durham, NC 27710
| | - M. Diaz
- Brain Imaging and Analysis Center, Duke University Medical Center, Durham, NC 27710
| | - C. G. Wible
- Department of Psychiatry, Harvard Medical School and Brockton VAMC, Radiology, Brigham Woman's Hospital, Boston, MA 02115
| | - J. M. Ford
- University of California, San Francisco, CA
| | | | - R. Gollub
- Neuroimaging Division, Department of Psychiatry, Massachusetts General Hospital, Charlestown, MA 02129
| | - J. Lauriello
- Department of Psychiatry, University of New Mexico, Albuquerque, NM 87131,The Mind Research Network, Albuquerque, NM 87131
| | - D. O'Leary
- Department of Psychiatry, University of Iowa, Iowa City, IA 52242
| | - T. G. M. van Erp
- Department of Psychology, University of California Los Angeles, CA 90095
| | - A. W. Toga
- Department of Neurology, University of California Los Angeles, CA 90095
| | - A. Preda
- Department of Psychiatry and Human Behavior, University of California Irvine, Irvine, CA 92697
| | - K. O. Lim
- Department of Psychiatry, University of Minnesota, Minneapolis, MN
| | | |
Collapse
|
127
|
Schubert MI, Porkess MV, Dashdorj N, Fone KCF, Auer DP. Effects of social isolation rearing on the limbic brain: a combined behavioral and magnetic resonance imaging volumetry study in rats. Neuroscience 2008; 159:21-30. [PMID: 19141315 DOI: 10.1016/j.neuroscience.2008.12.019] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2008] [Revised: 12/08/2008] [Accepted: 12/12/2008] [Indexed: 01/26/2023]
Abstract
Rearing rats in social isolation from weaning induces robust behavioral and neurobiological alterations resembling some of the core symptoms of schizophrenia, such as reduction in prepulse inhibition of acoustic startle (PPI) and locomotor hyperactivity in a novel arena. The aim of this study was to investigate whether social isolation rearing induces volumetric remodeling of the limbic system, and to probe for anatomical structure-behavioral interrelations. Isolation- (n=8) and group-reared (n=8) rats were examined by magnetic resonance (MR) volumetry using high-resolution T2-weighted imaging at 7 T. Volumes of medial prefrontal cortex (mPFC), anterior cingulate cortex (ACC), retrosplenial cortex (RSC) and hippocampal formation were compared between groups and with behavioral measures, i.e. PPI and locomotor activity in a novel arena. Isolation rearing induced locomotor hyperactivity and impaired PPI compared with group-housed rats. The right mPFC was significantly reduced (5.4%) in isolation-reared compared with group-reared rats, with a similar trend on the left side (5.2%). mPFC volumes changes were unrelated to behavioral abnormalities. No significant volume changes were observed in ACC, RSC or hippocampal formation. Hippocampal volumes were associated with the magnitude of PPI response in control but not in isolation-reared rats. Rearing rats in social isolation induced remodeling of the limbic brain with selective prefrontal cortex volume loss. In addition, a dissociation of the interrelation between hippocampal volume and PPI was noted in the isolation-reared rats. Taken together, limbic morphometry is sensitive to the effects of social isolation rearing but did not reveal direct brain-behavior interrelations, calling for more detailed circuitry analysis.
Collapse
Affiliation(s)
- M I Schubert
- Division of Academic Radiology, School of Clinical Sciences, University of Nottingham, Queen's Medical Centre, West Block, B Floor, Nottingham NG7 2UH, UK.
| | | | | | | | | |
Collapse
|
128
|
Abstract
OBJECTIVE The current study combined baseline voxel-based morphometry and 1-year clinical follow-up assessments to examine whether and where regional gray matter (GM) volumes differed between a control group and diagnostic subgroups of early-onset first-episode psychosis (FEP). METHOD Magnetic resonance imaging brain scans were obtained from 70 patients with early-onset FEP, and 51 non-FEP controls. Early-onset FEP was defined as age younger than 18 years and a duration of positive symptoms of less than 6 months. The age range of the sample was 7 to 18 years. After a 1-year follow-up, patients were stratified into three subgroups: schizophrenia (n = 25), bipolar I disorder (n = 20), and other psychoses (n = 25). Regional GM volumes of each patient subgroup were compared with those of the control group. RESULTS A follow-up diagnosis of schizophrenia was associated with GM volume deficits in the left medial and left middle frontal gyrus; bipolar I disorder was related to a GM volume deficit in the left medial frontal gyrus; and not having a follow-up diagnosis of schizophrenia or bipolar disorder was associated with smaller bilateral GM volumes in the insula and right middle occipital gyrus. CONCLUSIONS Left medial frontal GM volume deficits were common in the groups with schizophrenia and bipolar I disorder, which may point to shared underlying pathological findings.
Collapse
|
129
|
Mittal VA, Ellman LM, Cannon TD. Gene-environment interaction and covariation in schizophrenia: the role of obstetric complications. Schizophr Bull 2008; 34:1083-94. [PMID: 18635675 PMCID: PMC2632505 DOI: 10.1093/schbul/sbn080] [Citation(s) in RCA: 136] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
While genetic factors account for a significant proportion of liability to schizophrenia, a body of evidence attests to a significant environmental contribution. Understanding the mechanisms through which genetic and environmental factors coalesce in influencing schizophrenia is critical for elucidating the pathways underlying psychotic illness and for developing primary prevention strategies. Although obstetric complications (OCs) remain among the most well-documented environmental indicators of risk for schizophrenia, the pathogenic role they play in the etiology of schizophrenia continues to remain poorly understood. A question of major importance is do these factors result from a genetic diathesis to schizophrenia (as in gene-environment covariation), act additively or interactively with predisposing genes for the disorder in influencing disease risk, or independently cause disease onset? In this review, we evaluate 3 classes of OCs commonly related to schizophrenia including hypoxia-associated OCs, maternal infection during pregnancy, and maternal stress during pregnancy. In addition, we discuss several mechanisms by which OCs impact on genetically susceptible brain regions, increasing constitutional vulnerability to neuromaturational events and stressors later in life (ie, adolescence), which may in turn contribute to triggering psychosis.
Collapse
Affiliation(s)
- Vijay A. Mittal
- Department of Psychiatry and Biobehavioral Sciences, University of California Los Angeles, Los Angeles, CA
- Department of Psychology, University of California Los Angeles, Los Angeles, CA
| | | | - Tyrone D. Cannon
- Department of Psychiatry and Biobehavioral Sciences, University of California Los Angeles, Los Angeles, CA
- Department of Psychology, University of California Los Angeles, Los Angeles, CA
| |
Collapse
|
130
|
Three-dimensional brain growth abnormalities in childhood-onset schizophrenia visualized by using tensor-based morphometry. Proc Natl Acad Sci U S A 2008; 105:15979-84. [PMID: 18852461 DOI: 10.1073/pnas.0806485105] [Citation(s) in RCA: 105] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Earlier studies revealed progressive cortical gray matter (GM) loss in childhood-onset schizophrenia (COS) across both lateral and medial surfaces of the developing brain. Here, we use tensor-based morphometry to visualize white matter (WM) growth abnormalities in COS throughout the brain. Using high-dimensional elastic image registration, we compared 3D maps of local WM growth rates in COS patients and healthy children over a 5-year period, based on analyzing longitudinal brain MRIs from 12 COS patients and 12 healthy controls matched for age, gender, and scan interval. COS patients showed up to 2.2% slower growth rates per year than healthy controls in WM (P = 0.02, all P values corrected). The greatest differences were in the right hemisphere (P = 0.006). This asymmetry was attributable to a right slower than left hemisphere growth rate mapped in COS patients (P = 0.037) but not in healthy controls. WM growth rates reached 2.6% per year in healthy controls (P = 0.0002). COS patients showed only a 1.3% per year trend for growth in the left hemisphere (P = 0.066). In COS, WM growth rates were associated with improvement in the Children's Global Assessment Scale (R = 0.64, P = 0.029). Growth rates were reduced throughout the brain in COS, but this process appeared to progress in a front-to-back (frontal-parietal) fashion, and this effect was not attributable to lower IQ. Growth rates were correlated with functional prognosis and were visualized as detailed 3D maps. Finally, these findings also confirm that the progressive GM deficits seen in schizophrenia are not the result of WM overgrowth.
Collapse
|
131
|
Developmental disruptions in neural connectivity in the pathophysiology of schizophrenia. Dev Psychopathol 2008; 20:1297-327. [DOI: 10.1017/s095457940800062x] [Citation(s) in RCA: 115] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
AbstractSchizophrenia has been thought of as a disorder of reduced functional and structural connectivity. Recent advances in neuroimaging techniques such as functional magnetic resonance imaging, structural magnetic resonance imaging, diffusion tensor imaging, and small animal imaging have advanced our ability to investigate this hypothesis. Moreover, the power of longitudinal designs possible with these noninvasive techniques enable the study of not just how connectivity is disrupted in schizophrenia, but when this disruption emerges during development. This article reviews genetic and neurodevelopmental influences on structural and functional connectivity in human populations with or at risk for schizophrenia and in animal models of the disorder. We conclude that the weight of evidence across these diverse lines of inquiry points to a developmental disruption of neural connectivity in schizophrenia and that this disrupted connectivity likely involves susceptibility genes that affect processes involved in establishing intra- and interregional connectivity.
Collapse
|
132
|
Summary of the 1st Schizophrenia International Research Society Conference oral sessions, Venice, Italy, June 21-25, 2008: the rapporteur reports. Schizophr Res 2008; 105:289-383. [PMID: 18819775 DOI: 10.1016/j.schres.2008.08.015] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The Schizophrenia International Research Society held its first scientific conference in Venice, Italy, June 21 to 25th, 2008. A wide range of controversial topics were presented in overlapping and plenary oral sessions. These included new genetic studies, controversies about early detection of schizophrenia and the prodrome, treatment issues, clinical characteristics, cognition, neuropathology and neurophysiology, other etiological considerations, substance abuse co-morbidity, and animal models for investigating disease etiology and for use as targets in drug studies. Young investigators in the field were awarded travel grants to participate in the congress and one of their roles was to summarize the oral sessions and subsequent discussions. The reports that follow are the culmination of this work produced by 30 young investigators who attended the congress. It is hoped that these summaries will be useful synopses of what actually occurred at the congress for those who did not attend each session or were unable to be present. The abstracts of all presentations, as submitted by the authors a few months prior, were previously published as supplement 2 to volume 102/1-3, June 2008.
Collapse
|
133
|
Childhood-onset schizophrenia: insights from neuroimaging studies. J Am Acad Child Adolesc Psychiatry 2008; 47:1120-4. [PMID: 20566189 DOI: 10.1097/chi.0b013e31817eed7a] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 03/31/2008] [Indexed: 11/25/2022]
|
134
|
Prasad KM, Keshavan MS. Structural cerebral variations as useful endophenotypes in schizophrenia: do they help construct "extended endophenotypes"? Schizophr Bull 2008; 34:774-90. [PMID: 18408230 PMCID: PMC2632444 DOI: 10.1093/schbul/sbn017] [Citation(s) in RCA: 76] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Endophenotypes represent intermediate phenotypes on the putative causal pathway from the genotype to the phenotype. They offer a potentially valuable strategy to examine the molecular etiopathology of complex behavioral phenotypes such as schizophrenia. Neurocognitive and neurophysiological impairments that suggest functional impairments associated with schizophrenia have been proposed as endophenotypes. However, few studies have examined the structural variations in the brain that might underlie the functional impairments as useful endophenotypes for schizophrenia. Over the past three decades, there has been an impressive body of literature supporting brain structural alterations in schizophrenia. We critically reviewed the extant literature on the neuroanatomical variations in schizophrenia in this paper to evaluate their candidacy as endophenotypes and how useful they are in furthering the understanding of etiology and pathophysiology of schizophrenia. Brain morphometric measures meet many of the criteria set by different investigators, such as being robustly associated with schizophrenia, heritable, quantifiable, and present in unaffected family members more frequently than in the general population. We conclude that the brain morphometric alterations appear largely to meet the criteria for endophenotypes in psychotic disorders. Some caveats for the utility of endophenotypes are discussed. A proposal to combine more than one endophenotype ("extended endophenotype") is suggested. Further work is needed to examine how specific genes and their interactions with the environment may produce alterations in brain structure and function that accompany psychotic disorders.
Collapse
Affiliation(s)
- Konasale M. Prasad
- Western Psychiatric Institute and Clinic, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213
| | - Matcheri S. Keshavan
- Western Psychiatric Institute and Clinic, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213
- Department of Psychiatry and Behavioral Neuroscience, Wayne State University School of Medicine, Detroit, MI 48201
| |
Collapse
|
135
|
van Erp TG, Therman S, Pirkola T, Tuulio-Henriksson A, Glahn DC, Bachman P, Huttunen MO, Lönnqvist J, Hietanen M, Kaprio J, Koskenvuo M, Cannon TD. Verbal recall and recognition in twins discordant for schizophrenia. Psychiatry Res 2008; 159:271-80. [PMID: 18442861 PMCID: PMC2519867 DOI: 10.1016/j.psychres.2007.03.003] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/24/2005] [Revised: 10/31/2006] [Accepted: 03/11/2007] [Indexed: 10/22/2022]
Abstract
The nature, neural underpinnings, and etiology of deficits in verbal declarative memory in patients with schizophrenia remain unclear. To examine the contributions of genes and environment to verbal recall and recognition performance in this disorder, the California Verbal Learning Test was administered to a large population-based Finnish twin sample, which included schizophrenic and schizoaffective patients, their non-ill monozygotic (MZ) and dizygotic (DZ) co-twins, and healthy control twins. Compared with controls, patients and their co-twins showed relatively greater performance deficits on free recall compared with recognition. Intra-pair differences between patients and their non-ill co-twins in hippocampal volume and memory performance were highly positively correlated. These findings are consistent with the view that genetic influences are associated with reduced verbal recall in schizophrenia, but that non-genetic influences further compromise these abnormalities in patients who manifest the full-blown schizophrenia phenotype, with this additional degree of disease-related declarative memory deficit mediated in part by hippocampal pathology.
Collapse
Affiliation(s)
| | - Sebastian Therman
- Department of Mental Health and Alcohol Research, National Public Health Institute of Finland, Helsinki, Finland
| | - Tiia Pirkola
- Department of Mental Health and Alcohol Research, National Public Health Institute of Finland, Helsinki, Finland
| | - Annamari Tuulio-Henriksson
- Department of Mental Health and Alcohol Research, National Public Health Institute of Finland, Helsinki, Finland
| | - David C. Glahn
- Department of Psychiatry and Research Imaging Center, UTHSCA, San Antonio, TX, U. S.A
| | - Peter Bachman
- Department of Psychology, UCLA, Los Angeles, CA, U.S.A
| | - Matti O. Huttunen
- Department of Mental Health and Alcohol Research, National Public Health Institute of Finland, Helsinki, Finland
| | - Jouko Lönnqvist
- Department of Mental Health and Alcohol Research, National Public Health Institute of Finland, Helsinki, Finland
| | - Marja Hietanen
- Department of Neurology, University of Helsinki, Helsinki, Finland
| | - Jaakko Kaprio
- Department of Mental Health and Alcohol Research, National Public Health Institute of Finland, Helsinki, Finland, Department of Public Health, University of Helsinki, Helsinki, Finland
| | - Markku Koskenvuo
- Department of Public Health, University of Helsinki, Helsinki, Finland
| | - Tyrone D. Cannon
- Department of Psychology, UCLA, Los Angeles, CA, U.S.A., Department of Psychiatry and Biobehavioral Sciences, and Human Genetics, UCLA, CA, U.S.A
| |
Collapse
|
136
|
Arango C, Moreno C, Martínez S, Parellada M, Desco M, Moreno D, Fraguas D, Gogtay N, James A, Rapoport J. Longitudinal brain changes in early-onset psychosis. Schizophr Bull 2008; 34:341-53. [PMID: 18234701 PMCID: PMC2632400 DOI: 10.1093/schbul/sbm157] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Progressive losses of cortical gray matter volumes and increases in ventricular volumes have been reported in patients with childhood-onset schizophrenia (COS) during adolescence. Longitudinal studies suggest that the rate of cortical loss seen in COS during adolescence plateaus during early adulthood. Patients with first-episode adolescent-onset schizophrenia show less marked progressive changes, although the number of studies in this population is small. Some studies show that, although less exaggerated, progressive changes are also present in nonschizophrenia early-onset psychosis. The greater loss of brain tissue seen in COS, even some years after the first episode, as compared to adolescent- or adult-onset schizophrenia may be due to variables such as sample bias (more severe, treatment refractory sample of childhood-onset patients studied), a process uniquely related to adolescent development in COS, differential brain effects of drug treatment in this population, clinical outcome, or interactions among these variables. Findings from both cross-sectional studies of first-episode patients and longitudinal studies in COS and adolescent onset support the concept of early-onset schizophrenia as a progressive neurodevelopmental disorder with both early and late developmental abnormalities. Future studies should look for correlates at a cellular level and for pathophysiological explanations of volume changes in these populations. The association of risk genes involved in circuitries associated with schizophrenia and their relationship to developmental trajectories is another promising area of future research.
Collapse
Affiliation(s)
- Celso Arango
- Adolescent Unit, Department of Psychiatry, Hospital General Universitario Gregorio Marañón, Madrid, Spain.
| | - Carmen Moreno
- Adolescent Unit, Department of Psychiatry, Hospital General Universitario Gregorio Marañón, Madrid, Spain
| | - Salvador Martínez
- Instituto de Neurociencias, Universidad Miguel Hernandez, Alicante, Spain
| | - Mara Parellada
- Adolescent Unit, Department of Psychiatry, Hospital General Universitario Gregorio Marañón, Madrid, Spain
| | - Manuel Desco
- Unidad de Medicina y Cirugía Experimental, Hospital General Universitario Gregorio Marañón, Madrid, Spain
| | | | - David Fraguas
- Adolescent Unit, Department of Psychiatry, Hospital General Universitario Gregorio Marañón, Madrid, Spain
| | - Nitin Gogtay
- Child Psychiatry Branch, National Institute of Mental Health, Room 3N202, Building 10, Center Drive, Bethesda, MD 20892
| | - Anthony James
- Highfield Adolescent Unit, Warneford Hospital, Oxford, UK
| | - Judith Rapoport
- Child Psychiatry Branch, National Institute of Mental Health, Room 3N202, Building 10, Center Drive, Bethesda, MD 20892
| |
Collapse
|
137
|
Honea RA, Meyer-Lindenberg A, Hobbs KB, Pezawas L, Mattay VS, Egan MF, Verchinski B, Passingham RE, Weinberger DR, Callicott JH. Is gray matter volume an intermediate phenotype for schizophrenia? A voxel-based morphometry study of patients with schizophrenia and their healthy siblings. Biol Psychiatry 2008; 63:465-74. [PMID: 17689500 PMCID: PMC2390785 DOI: 10.1016/j.biopsych.2007.05.027] [Citation(s) in RCA: 153] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/06/2007] [Revised: 04/30/2007] [Accepted: 05/22/2007] [Indexed: 02/06/2023]
Abstract
BACKGROUND Shared neuropathological characteristics of patients with schizophrenia and their siblings might represent intermediate phenotypes that could be used to investigate genetic susceptibility to the illness. We sought to discover previously unidentified gray matter volume differences in patients with schizophrenia and their siblings with optimized voxel-based morphometry. METHODS We studied 169 patients with schizophrenia, 213 of their unaffected siblings, and 212 healthy volunteers from the Clinical Brain Disorders Branch/National Institute of Mental Health Genetic Study of Schizophrenia with magnetic resonance imaging. RESULTS Patients with schizophrenia had significant regional gray matter decreases in the frontal, temporal, and parietal cortices compared with healthy volunteers. Their unaffected siblings tended to share gray matter decreases in the medial frontal, superior temporal, and insular cortices, but these decreases were not significant after correction for multiple comparisons, even when we looked at a subgroup of siblings with a past history of mood disorder. As an exploratory analysis, we estimated heritability with regions of interest from the VBM analysis as well as from the hippocampus. Hippocampal volume was significantly correlated within sibling-pairs. CONCLUSIONS Our findings confirm and extend previous voxel-based morphometry analyses in ill subjects with schizophrenia. Furthermore, these data argue that although siblings might share some regional gray matter decreases with their affected siblings, the pattern of regional differences might be a weak intermediate phenotype for schizophrenia.
Collapse
Affiliation(s)
- Robyn A Honea
- Genes, Cognition and Psychosis Program, National Institute of Mental Health, Division of Intramural Research, National Institutes of Health, Department of Health and Human Services, Bethesda, Maryland 20892-1364, USA
| | | | | | | | | | | | | | | | | | | |
Collapse
|
138
|
Tan HY, Callicott JH, Weinberger DR. Intermediate phenotypes in schizophrenia genetics redux: is it a no brainer? Mol Psychiatry 2008; 13:233-8. [PMID: 18285755 DOI: 10.1038/sj.mp.4002145] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
|
139
|
Lawrie SM, McIntosh AM, Hall J, Owens DGC, Johnstone EC. Brain structure and function changes during the development of schizophrenia: the evidence from studies of subjects at increased genetic risk. Schizophr Bull 2008; 34:330-40. [PMID: 18227083 PMCID: PMC2632417 DOI: 10.1093/schbul/sbm158] [Citation(s) in RCA: 135] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
This article reviews the evidence for changes in the structure and function of the brain in subjects at high risk of schizophrenia for genetic reasons during the genesis of the disorder. We first highlight the structural and functional abnormalities in schizophrenia and whether any similar or lesser abnormalities are apparent in unaffected relatives. There is good evidence for subtle abnormalities of hippocampal and ventricle volume in relatives that are not as marked as the deficits in schizophrenia. In addition, the functional imaging literature suggests that prefrontal cortex function may deteriorate in those at risk who go on to develop the disorder. We then review the findings from longitudinal imaging studies of those at high risk, particularly the Edinburgh High-Risk Study, which report gray matter density reductions in medial and lateral temporal lobe because people develop schizophrenia, as well as functional abnormalities which precede onset. We conclude by quoting our own and others' imaging studies of the associations of genetic and other risk factors for schizophrenia, including stressful life events and cannabis use, which provide mechanistic examples of how these changes may be brought about. Overall, the literature supports the view that there are measurable changes in brain structure and function during the genesis of the disorder, which provide opportunities for early detection and intervention.
Collapse
Affiliation(s)
- Stephen M Lawrie
- Division of Psychiatry, University of Edinburgh, Royal Edinburgh Hospital, Edinburgh EH10 5HF, Scotland, UK.
| | | | | | | | | |
Collapse
|
140
|
Lawrie SM, Hall J, McIntosh AM, Cunningham-Owens DG, Johnstone EC. Neuroimaging and molecular genetics of schizophrenia: pathophysiological advances and therapeutic potential. Br J Pharmacol 2008; 153 Suppl 1:S120-4. [PMID: 18193072 DOI: 10.1038/sj.bjp.0707655] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
There is impressive evidence for the involvement of several genetic risk factors in the aetiopathogenesis of schizophrenia. Most of these genes impact on neuropharmacological systems. Examining their relationship with brain imaging indices is arguably the best currently available method of examining these effects in vivo. In a sample of young, initially healthy people at high genetic risk of schizophrenia brain structure was measured with structural magnetic resonance imaging (sMRI) and brain function was indexed with neuropsychological tests and functional MRI. Regular detailed clinical assessments established whether subjects had developed psychotic symptoms and/or schizophrenia itself. The Catechol-O-Methyl Transferase (COMT) Val allele increased the risk of schizophrenia in this cohort in a dose-dependent manner. Subjects with this allele had reduced grey matter density in anterior cingulate cortex and increased fMRI activation in lateral prefrontal cortex and anterior and posterior cingulate. The risk allele in the Neuregulin 1 (NRG1) promoter region, on the other hand, was associated with the development of psychotic symptoms, decreased premorbid IQ and decreased activation of pre-frontal and temporal lobe regions. The NRG1 gene appears to be a risk factor for an extended or intermediate phenotype, while the COMT Val allele, which decreases the rate at which cortical dopamine is degraded compared to the Met allele, is associated with an increased risk of schizophrenia in subjects at increased familial risk. We provide examples of how these advances in our knowledge could lead to the development of new treatments for psychosis.
Collapse
Affiliation(s)
- S M Lawrie
- Division of Psychiatry, University of Edinburgh, Edinburgh, UK.
| | | | | | | | | |
Collapse
|
141
|
Lenroot RK, Giedd JN. The changing impact of genes and environment on brain development during childhood and adolescence: initial findings from a neuroimaging study of pediatric twins. Dev Psychopathol 2008; 20:1161-75. [PMID: 18838036 PMCID: PMC2892674 DOI: 10.1017/s0954579408000552] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Human brain development is created through continuing complex interactions of genetic and environmental influences. The challenge of linking specific genetic or environmental risk factors to typical or atypical behaviors has led to interest in using brain structural features as an intermediate phenotype. Twin studies in adults have found that many aspects of brain anatomy are highly heritable, demonstrating that genetic factors provide a significant contribution to variation in brain structures. Less is known about the relative impact of genes and environment while the brain is actively developing. We summarize results from the ongoing National Institute of Mental Health child and adolescent twin study that suggest that heritability of different brain areas changes over the course of development in a regionally specific fashion. Areas associated with more complex reasoning abilities become increasingly heritable with maturation. The potential mechanisms by which gene-environment interactions may affect heritability values during development is discussed.
Collapse
|
142
|
Rapoport JL, Gogtay N. Brain neuroplasticity in healthy, hyperactive and psychotic children: insights from neuroimaging. Neuropsychopharmacology 2008; 33:181-97. [PMID: 17851542 DOI: 10.1038/sj.npp.1301553] [Citation(s) in RCA: 99] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Noninvasive brain imaging permits longitudinal studies of anatomic brain development in healthy and psychiatrically ill children. The time course for gray matter maturation varies by region and parallels earlier histological studies, indicating dynamic patterns of overproduction and regression. Developmental trajectories vary in relation to gender, intelligence, and overall functioning. Twin studies show high heritability for brain volumes, which varies with region and with age. Diagnostically specific, illness-related changes as well as outcome-associated plastic response are observed as illustrated for two pediatric populations, childhood-onset schizophrenia and attention-deficit/hyperactivity disorder, conditions which may be, in part, disorders of brain plasticity.
Collapse
|
143
|
Specific developmental disruption of disrupted-in-schizophrenia-1 function results in schizophrenia-related phenotypes in mice. Proc Natl Acad Sci U S A 2007; 104:18280-5. [PMID: 17984054 DOI: 10.1073/pnas.0706900104] [Citation(s) in RCA: 185] [Impact Index Per Article: 10.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Disrupted-in-schizophrenia 1 (DISC1) was initially discovered through a balanced translocation (1;11)(q42.1;q14.3) that results in loss of the C terminus of the DISC1 protein, a region that is thought to play an important role in brain development. Here, we use an inducible and reversible transgenic system to demonstrate that early postnatal, but not adult induction, of a C-terminal portion of DISC1 in mice results in a cluster of schizophrenia-related phenotypes, including reduced hippocampal dendritic complexity, depressive-like traits, abnormal spatial working memory, and reduced sociability. Accordingly, we report that individuals in a discordant twin sample with a DISC1 haplotype, associating with schizophrenia as well as working memory impairments and reduced gray matter density, were more likely to show deficits in sociability than those without the haplotype. Our findings demonstrate that alterations in DISC1 function during brain development contribute to schizophrenia pathogenesis.
Collapse
|
144
|
Szeszko PR, Hodgkinson CA, Robinson DG, Derosse P, Bilder RM, Lencz T, Burdick KE, Napolitano B, Betensky JD, Kane JM, Goldman D, Malhotra AK. DISC1 is associated with prefrontal cortical gray matter and positive symptoms in schizophrenia. Biol Psychol 2007; 79:103-10. [PMID: 18078707 DOI: 10.1016/j.biopsycho.2007.10.011] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2007] [Revised: 10/16/2007] [Accepted: 10/16/2007] [Indexed: 02/02/2023]
Abstract
BACKGROUND DISC1 is considered a susceptibility gene for schizophrenia and schizoaffective disorder, but little is known regarding the potential mechanisms through which it may confer increased risk. Given that DISC1 plays a role in cerebral cortex development, polymorphisms in this gene may have relevance for neurobiological models of schizophrenia that have implicated cortical deficits in its pathophysiology. METHODS We investigated whether the DISC1 leu607phe polymorphism was associated with prefrontal gray matter volumes using magnetic resonance imaging in a cohort of patients with schizophrenia (N=19) and healthy volunteers (N=25) and positive and negative symptoms in 200 patients with schizophrenia. RESULTS Among patients and healthy volunteers, phe carriers (N=11) had significantly less gray matter in the superior frontal gyrus and anterior cingulate gyrus compared to leu/leu homozygotes (N=33). Further, among patients left superior frontal gyrus gray matter volume was significantly negatively correlated with severity of hallucinations. In addition, patients who were phe carriers (N=144) had significantly greater severity of positive symptoms (hallucinations) compared to patients who were leu/leu homozygotes (N=56). DISCUSSION These findings implicate DISC1 in variation of prefrontal cortical volume and positive symptoms, thus providing a potential mechanism through which DISC1 may confer increased risk for schizophrenia or schizoaffective disorder.
Collapse
|
145
|
Abstract
To date, the diagnosis of mental disorders has been based on clinical observation, specifically: the identification of symptoms that tend to cluster together, the timing of the symptoms' appearance, and their tendency to resolve, recur or become chronic. The Diagnostic and Statistical Manual of Mental Disorders and the International Classification of Disease, the manuals that specify these diagnoses and the criteria for making them, are currently undergoing revision. It is thus timely to ask whether neuroscience has progressed to the point that the next editions of these manuals can usefully incorporate information about brain structure and function.
Collapse
Affiliation(s)
- Steven E Hyman
- Harvard University, Massachusetts Hall, Cambridge, Massachusetts 02138, USA.
| |
Collapse
|
146
|
|
147
|
Keshavan MS, Prasad KM, Pearlson G. Are brain structural abnormalities useful as endophenotypes in schizophrenia? Int Rev Psychiatry 2007; 19:397-406. [PMID: 17671872 DOI: 10.1080/09540260701486233] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Endophenotypes, which represent intermediate phenotypes on the causal pathway from the genotype to the phenotype, can help unravel the molecular etiopathology of complex psychiatric disorders such as schizophrenia. Several candidate endophenotypic markers have been proposed in schizophrenia, including neurocognitive and neurophysiological impairments. Over the past three decades, there has been an impressive body of literature in support of brain structural alterations in schizophrenia, but few studies have critically examined whether these abnormalities can be considered useful endophenotypic markers. We critically reviewed the extant literature on the neuroanatomy of schizophrenia in this paper to evaluate their candidacy as endophenotypes. Structural brain changes are robustly associated with schizophrenia, are state independent and may cut across the diagnostic boundaries of major psychotic illnesses. Brain morphometric measures are heritable, co-segregate with the broadly defined neurocognitive and behavioural phenotypes within the first degree relatives of schizophrenia patients and are present in unaffected family members more frequently than in the general population. Taken together, brain morphometric alterations appear largely to meet the criteria for endophenotypes in psychotic disorders. Further work is needed to examine how specific genes and their interactions with the environment may produce alterations in brain structure and function that accompany psychotic disorders.
Collapse
Affiliation(s)
- Matcheri S Keshavan
- Department of Psychiatry, Wayne State University School of Medicine, 4201 St. Antoine Boulevard, Detroit, MA 48201, USA.
| | | | | |
Collapse
|
148
|
Woodward ND, Tibbo P, Purdon SE. An fMRI investigation of procedural learning in unaffected siblings of individuals with schizophrenia. Schizophr Res 2007; 94:306-16. [PMID: 17544630 DOI: 10.1016/j.schres.2007.04.026] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/09/2006] [Revised: 04/06/2007] [Accepted: 04/06/2007] [Indexed: 11/22/2022]
Abstract
Vulnerability for schizophrenia is related, in part, to genetic predisposition. The identification of pathophysiological abnormalities associated with the disorder that are also present in unaffected family members of individuals with schizophrenia may assist in delineating the genetic contributions to vulnerability for schizophrenia. Previous functional Magnetic Resonance Imaging (fMRI) investigations of procedural learning in patients with schizophrenia identified reduced activity in the frontal cortex, basal ganglia, and parietal cortex during performance of the serial reaction time (SRT) task suggesting that abnormal function of these regions may relate to genetic vulnerability for schizophrenia. In order to examine this hypothesis, 12 unaffected siblings of patients and 15 controls underwent fMRI during performance of the SRT task. Unaffected siblings demonstrated normal performance on the SRT task. However, compared to controls unaffected siblings demonstrated less activity in regions of the frontal and parietal lobes and, to a lesser extent, basal ganglia, during procedural learning. Interestingly, unaffected siblings demonstrated greater activity in regions of the frontal cortex during the control condition compared to the procedural learning condition of the SRT task, an idiosyncratic pattern that was also observed in patient groups but not control subjects of two prior imaging studies. The findings support previous investigations suggesting that altered cerebral neurophysiology during performance of cognitive tasks may be related to genetic vulnerability for schizophrenia. Identification of genes related to the function of cerebral regions such as the prefrontal cortex, parietal lobe, and basal ganglia may assist in delineating the genetic contributions to schizophrenia.
Collapse
Affiliation(s)
- Neil D Woodward
- Department of Psychology, Vanderbilt University, Nashville, TN 37203, USA.
| | | | | |
Collapse
|
149
|
Bearden CE, van Erp TGM, Thompson PM, Toga AW, Cannon TD. Cortical mapping of genotype-phenotype relationships in schizophrenia. Hum Brain Mapp 2007; 28:519-32. [PMID: 17437284 PMCID: PMC3184848 DOI: 10.1002/hbm.20404] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Although schizophrenia is highly heritable, the search for susceptibility genes has been challenging. The "endophenotype" approach is an alternative method for measuring phenotypic variation that may make it easier to identify susceptibility genes in the context of complexly inherited traits. Neuroimaging methods in particular offer a powerful way to bridge the neurobiology of genes and behavior. Such investigations may be further empowered by complementary strategies involving chromosomal abnormalities associated with schizophrenia, which can help to localize causative genes and better understand the genetic complexity of the illness. Here, we illustrate our use of these convergent approaches, with a focus on neuroimaging studies using novel computational brain mapping algorithms, to investigate genetic influences on brain structure in the development of psychosis. These studies provide compelling evidence that specific genetic loci suspected to predispose to schizophrenia may affect quantitative variation in neural indicators underlying the neurobehavioral phenotype, and illustrate how genetic-neuroimaging paradigms can improve our understanding of the pathogenesis of this highly disabling mental illness.
Collapse
Affiliation(s)
- Carrie E Bearden
- Department of Psychiatry and Biobehavioral Sciences, Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, California 90095, USA.
| | | | | | | | | |
Collapse
|
150
|
Salisbury DF, Kuroki N, Kasai K, Shenton ME, McCarley RW. Progressive and interrelated functional and structural evidence of post-onset brain reduction in schizophrenia. ACTA ACUST UNITED AC 2007; 64:521-9. [PMID: 17485604 PMCID: PMC2903200 DOI: 10.1001/archpsyc.64.5.521] [Citation(s) in RCA: 293] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
CONTEXT Progressive brain abnormalities in schizophrenia remain controversial. Evidence of interrelated progressive functional impairment would buttress the case for structural progression. Mismatch negativity (MMN) is reduced in chronic but not first-hospitalized schizophrenia and may index progressive structural changes. OBJECTIVE To determine whether MMN shows associations with underlying auditory cortex gray matter at first hospitalization and progressive reduction longitudinally. DESIGN Cross-sectional (first hospitalization) and longitudinal (1.5-year follow-up). SETTING A private psychiatric hospital. PARTICIPANTS Protocol entrance: MMN and magnetic resonance imaging at first hospitalization in 20 subjects with schizophrenia, 21 subjects with bipolar disorder with psychosis, and 32 control subjects. Longitudinal electrophysiologic testing: MMN in 16 subjects with schizophrenia, 17 subjects with bipolar disorder, and 20 control subjects. Longitudinal electrophysiologic testing and magnetic resonance imaging: MMN and magnetic resonance imaging in 11 subjects with schizophrenia, 13 subjects with bipolar disorder, and 13 control subjects. At each time point, reported samples were group matched for age, handedness, and parental socioeconomic status. INTERVENTIONS Electrophysiologic testing and high-resolution structural magnetic resonance imaging. MAIN OUTCOME MEASURES Mismatch negativity amplitude and Heschl gyrus and planum temporale gray matter volumes. RESULTS Initially, groups did not differ in MMN amplitude. Subjects with schizophrenia showed associations between MMN and Heschl gyrus (r=-0.52; P=.02) not present in the other groups. At longitudinal MMN testing, schizophrenia showed MMN reduction (P=.004). Only schizophrenia evinced longitudinal left hemisphere Heschl gyrus reduction (P=.003), highly correlated with MMN reduction (r=0.6; P=.04). CONCLUSIONS At first hospitalization for schizophrenia, MMN indexed left hemisphere Heschl gyrus gray matter volume, consistent with variable progression of pre-hospitalization cortical reduction. Longitudinally, the interrelated progressive reduction of functional and structural measures suggests progressive pathologic processes early in schizophrenia. An active process of progressive cortical reduction presents a potential therapeutic target. Mismatch negativity may be a simple, sensitive, and inexpensive index not only of this progressive pathologic process but also of successful intervention.
Collapse
Affiliation(s)
- Dean F Salisbury
- Veterans Affairs Boston Healthcare System, Brockton Division, Brockton, Boston, MA, USA.
| | | | | | | | | |
Collapse
|