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1.
Psychol Med ; 53(6): 2370-2379, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37310314

RESUMO

BACKGROUND: Psychotic-like experiences (PLEs) are risk factors for the development of psychiatric conditions like schizophrenia, particularly if associated with distress. As PLEs have been related to alterations in both white matter and cognition, we investigated whether cognition (g-factor and processing speed) mediates the relationship between white matter and PLEs. METHODS: We investigated two independent samples (6170 and 19 891) from the UK Biobank, through path analysis. For both samples, measures of whole-brain fractional anisotropy (gFA) and mean diffusivity (gMD), as indications of white matter microstructure, were derived from probabilistic tractography. For the smaller sample, variables whole-brain white matter network efficiency and microstructure were also derived from structural connectome data. RESULTS: The mediation of cognition on the relationships between white matter properties and PLEs was non-significant. However, lower gFA was associated with having PLEs in combination with distress in the full available sample (standardized ß = -0.053, p = 0.011). Additionally, lower gFA/higher gMD was associated with lower g-factor (standardized ß = 0.049, p < 0.001; standardized ß = -0.027, p = 0.003), and partially mediated by processing speed with a proportion mediated of 7% (p = < 0.001) for gFA and 11% (p < 0.001) for gMD. CONCLUSIONS: We show that lower global white matter microstructure is associated with having PLEs in combination with distress, which suggests a direction of future research that could help clarify how and why individuals progress from subclinical to clinical psychotic symptoms. Furthermore, we replicated that processing speed mediates the relationship between white matter microstructure and g-factor.


Assuntos
Transtornos Mentais , Substância Branca , Humanos , Substância Branca/diagnóstico por imagem , Bancos de Espécimes Biológicos , Cognição , Reino Unido
2.
Mol Psychiatry ; 26(6): 2651-2662, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33398085

RESUMO

Different brain regions can be grouped together, based on cross-sectional correlations among their cortical characteristics; this patterning has been used to make inferences about ageing processes. However, cross-sectional brain data conflate information on ageing with patterns that are present throughout life. We characterised brain cortical ageing across the eighth decade of life in a longitudinal ageing cohort, at ages ~73, ~76, and ~79 years, with a total of 1376 MRI scans. Volumetric changes among cortical regions of interest (ROIs) were more strongly correlated (average r = 0.805, SD = 0.252) than were cross-sectional volumes of the same ROIs (average r = 0.350, SD = 0.178). We identified a broad, cortex-wide, dimension of atrophy that explained 66% of the variance in longitudinal changes across the cortex. Our modelling also discovered more specific fronto-temporal and occipito-parietal dimensions that were orthogonal to the general factor and together explained an additional 20% of the variance. The general factor was associated with declines in general cognitive ability (r = 0.431, p < 0.001) and in the domains of visuospatial ability (r = 0.415, p = 0.002), processing speed (r = 0.383, p < 0.001) and memory (r = 0.372, p < 0.001). Individual differences in brain cortical atrophy with ageing are manifest across three broad dimensions of the cerebral cortex, the most general of which is linked with cognitive declines across domains. Longitudinal approaches are invaluable for distinguishing lifelong patterns of brain-behaviour associations from patterns that are specific to aging.


Assuntos
Disfunção Cognitiva , Idoso , Envelhecimento , Encéfalo/diagnóstico por imagem , Córtex Cerebral/diagnóstico por imagem , Estudos Transversais , Humanos
3.
Transl Psychiatry ; 10(1): 122, 2020 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-32341335

RESUMO

Schizophrenia is a highly heritable disorder with considerable phenotypic heterogeneity. Hallmark psychotic symptoms can be considered as existing on a continuum from non-clinical to clinical populations. Assessing genetic risk and psychotic-like experiences (PLEs) in non-clinical populations and their associated neurobiological underpinnings can offer valuable insights into symptom-associated brain mechanisms without the potential confounds of the effects of schizophrenia and its treatment. We leveraged a large population-based cohort (UKBiobank, N = 3875) including information on PLEs (obtained from the Mental Health Questionnaire (MHQ); UKBiobank Category: 144; N auditory hallucinations = 55, N visual hallucinations = 79, N persecutory delusions = 16, N delusions of reference = 13), polygenic risk scores for schizophrenia (PRSSZ) and multi-modal brain imaging in combination with network neuroscience. Morphometric (cortical thickness, volume) and water diffusion (fractional anisotropy) properties of the regions and pathways belonging to the salience, default-mode, and central-executive networks were computed. We hypothesized that these anatomical concomitants of functional dysconnectivity would be negatively associated with PRSSZ and PLEs. PRSSZ was significantly associated with a latent measure of cortical thickness across the salience network (r = -0.069, p = 0.010) and PLEs showed a number of significant associations, both negative and positive, with properties of the salience and default mode networks (involving the insular cortex, supramarginal gyrus, and pars orbitalis, pFDR < 0.050); with the cortical thickness of the insula largely mediating the relationship between PRSSZ and auditory hallucinations. Generally, these results are consistent with the hypothesis that higher genetic liability for schizophrenia is related to subtle disruptions in brain structure and may predispose to PLEs even among healthy participants. In addition, our study suggests that networks engaged during auditory hallucinations show structural associations with PLEs in the general population.


Assuntos
Transtornos Psicóticos , Esquizofrenia , Bancos de Espécimes Biológicos , Voluntários Saudáveis , Humanos , Imageamento por Ressonância Magnética , Transtornos Psicóticos/diagnóstico por imagem , Transtornos Psicóticos/genética , Fatores de Risco , Esquizofrenia/diagnóstico por imagem , Esquizofrenia/genética , Reino Unido
4.
Soc Psychiatry Psychiatr Epidemiol ; 54(12): 1505-1518, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31123787

RESUMO

BACKGROUND: Self-harm is common, debilitating and associated with completed suicide and increased all-cause mortality, but there is uncertainty about its causal risk factors, limiting risk assessment and effective management. Neuroticism is a stable personality trait associated with self-harm and suicidal ideation, and correlated with coping styles, but its value as an independent predictor of these outcomes is disputed. METHODS: Prior history of hospital-treated self-harm was obtained by record-linkage to administrative health data in Generation Scotland:Scottish Family Health Study (N = 15,798; self-harm cases = 339) and by a self-report variable in UK Biobank (N = 35,227; self-harm cases = 772). Neuroticism in both cohorts was measured using the Eysenck Personality Questionnaire-Short Form. Associations of neuroticism with self-harm were tested using multivariable regression following adjustment for age, sex, cognitive ability, educational attainment, socioeconomic deprivation, and relationship status. A subset of GS:SFHS was followed-up with suicidal ideation elicited by self-report (n = 3342, suicidal ideation cases = 158) and coping styles measured by the Coping Inventory for Stressful Situations. The relationship of neuroticism to suicidal ideation, and the role of coping style, was then investigated using multivariable logistic regression. RESULTS: Neuroticism was positively associated with hospital-associated self-harm in GS:SFHS (per EPQ-SF unit odds ratio 1.2 95% credible interval 1.1-1.2, pFDR 0.0003) and UKB (per EPQ-SF unit odds ratio 1.1 95% confidence interval 1.1-1.2, pFDR 9.8 × 10-17). Neuroticism, and the neuroticism-correlated coping style, emotion-oriented coping (EoC), were also associated with suicidal ideation in multivariable models. CONCLUSIONS: Neuroticism is an independent predictor of hospital-treated self-harm risk. Neuroticism and emotion-orientated coping styles are also predictive of suicidal ideation.


Assuntos
Neuroticismo , Comportamento Autodestrutivo/psicologia , Ideação Suicida , Adaptação Psicológica , Adolescente , Adulto , Emoções , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Análise de Regressão , Fatores de Risco , Escócia , Autorrelato , Estresse Psicológico/psicologia , Reino Unido , Adulto Jovem
5.
Neuroimage ; 183: 884-896, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-30179718

RESUMO

Higher polygenic risk score for schizophrenia (szPGRS) has been associated with lower cognitive function and might be a predictor of decline in brain structure in apparently healthy populations. Age-related declines in structural brain connectivity-measured using white matter diffusion MRI -are evident from cross-sectional data. Yet, it remains unclear how graph theoretical metrics of the structural connectome change over time, and whether szPGRS is associated with differences in ageing-related changes in human brain connectivity. Here, we studied a large, relatively healthy, same-year-of-birth, older age cohort over a period of 3 years (age ∼ 73 years, N = 731; age ∼76 years, N = 488). From their brain scans we derived tract-averaged fractional anisotropy (FA) and mean diffusivity (MD), and network topology properties. We investigated the cross-sectional and longitudinal associations between these structural brain variables and szPGRS. Higher szPGRS showed significant associations with longitudinal increases in MD in the splenium (ß = 0.132, pFDR = 0.040), arcuate (ß = 0.291, pFDR = 0.040), anterior thalamic radiations (ß = 0.215, pFDR = 0.040) and cingulum (ß = 0.165, pFDR = 0.040). Significant declines over time were observed in graph theory metrics for FA-weighted networks, such as mean edge weight (ß = -0.039, pFDR = 0.048) and strength (ß = -0.027, pFDR = 0.048). No significant associations were found between szPGRS and graph theory metrics. These results are consistent with the hypothesis that szPGRS confers risk for ageing-related degradation of some aspects of structural connectivity.


Assuntos
Encéfalo/patologia , Conectoma/métodos , Esquizofrenia/genética , Esquizofrenia/patologia , Substância Branca/patologia , Idoso , Encéfalo/diagnóstico por imagem , Estudos Transversais , Imagem de Tensor de Difusão , Humanos , Estudos Longitudinais , Herança Multifatorial , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/patologia , Fatores de Risco , Esquizofrenia/diagnóstico por imagem , Substância Branca/diagnóstico por imagem
6.
Psychol Med ; 48(9): 1532-1539, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29065934

RESUMO

BACKGROUND: Schizophrenia is a highly heritable disorder, linked to several structural abnormalities of the brain. More specifically, previous findings have suggested that increased gyrification in frontal and temporal regions are implicated in the pathogenesis of schizophrenia. METHODS: The current study included participants at high familial risk of schizophrenia who remained well (n = 31), who developed sub-diagnostic symptoms (n = 28) and who developed schizophrenia (n = 9) as well as healthy controls (HC) (n = 16). We first tested whether individuals at high familial risk of schizophrenia carried an increased burden of trait-associated alleles using polygenic risk score analysis. We then assessed the extent to which polygenic risk was associated with gyral folding in the frontal and temporal lobes. RESULTS: We found that individuals at high familial risk of schizophrenia who developed schizophrenia carried a significantly greater burden of risk-conferring variants for the disorder compared to those at high risk (HR) who developed sub-diagnostic symptoms or remained well and HC. Furthermore, within the HR cohort, there was a significant and positive association between schizophrenia polygenic risk score and bilateral frontal gyrification. CONCLUSIONS: These results suggest that polygenic risk for schizophrenia impacts upon early neurodevelopment to confer greater gyral folding in adulthood and an increased risk of developing the disorder.


Assuntos
Herança Multifatorial , Esquizofrenia/genética , Esquizofrenia/patologia , Lobo Temporal/patologia , Adolescente , Adulto , Feminino , Predisposição Genética para Doença , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Polimorfismo de Nucleotídeo Único , Estudos Prospectivos , Medição de Risco , Adulto Jovem
7.
Sci Rep ; 7: 42140, 2017 02 10.
Artigo em Inglês | MEDLINE | ID: mdl-28186152

RESUMO

Major depressive disorder (MDD), schizophrenia (SCZ) and bipolar disorder (BP) are common, disabling and heritable psychiatric diseases with a complex overlapping polygenic architecture. Individuals with these disorders, as well as their unaffected relatives, show widespread structural differences in corticostriatal and limbic networks. Structural variation in many of these brain regions is also heritable and polygenic but whether their genetic architecture overlaps with that of major psychiatric disorders is unknown. We sought to address this issue by examining the impact of polygenic risk of MDD, SCZ, and BP on subcortical brain volumes and white matter (WM) microstructure in a large single sample of neuroimaging data; the UK Biobank Imaging study. The first release of UK Biobank imaging data comprised participants with overlapping genetic data and subcortical volumes (N = 978) and WM measures (N = 816). The calculation of polygenic risk scores was based on genome-wide association study results generated by the Psychiatric Genomics Consortium. Our findings indicated no statistically significant associations between either subcortical volumes or WM microstructure, and polygenic risk for MDD, SCZ or BP. These findings suggest that subcortical brain volumes and WM microstructure may not be closely linked to the genetic mechanisms of major psychiatric disorders.


Assuntos
Transtorno Bipolar/diagnóstico por imagem , Córtex Cerebral/diagnóstico por imagem , Transtorno Depressivo Maior/diagnóstico por imagem , Herança Multifatorial , Esquizofrenia/diagnóstico por imagem , Substância Branca/diagnóstico por imagem , Adulto , Idoso , Bancos de Espécimes Biológicos , Transtorno Bipolar/genética , Transtorno Bipolar/metabolismo , Transtorno Bipolar/patologia , Mapeamento Encefálico , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Corpo Estriado/diagnóstico por imagem , Corpo Estriado/metabolismo , Corpo Estriado/patologia , Transtorno Depressivo Maior/genética , Transtorno Depressivo Maior/metabolismo , Transtorno Depressivo Maior/patologia , Feminino , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Humanos , Sistema Límbico/diagnóstico por imagem , Sistema Límbico/metabolismo , Sistema Límbico/patologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neuroimagem , Risco , Esquizofrenia/genética , Esquizofrenia/metabolismo , Esquizofrenia/patologia , Substância Branca/metabolismo , Substância Branca/patologia
8.
Transl Psychiatry ; 6(11): e938, 2016 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-27801894

RESUMO

Major depressive disorder (MDD) is known for its substantial clinical and suspected causal heterogeneity. It is characterized by low mood, psychomotor slowing and increased levels of the personality trait neuroticism; factors also associated with schizophrenia (SCZ). It is possible that some cases of MDD may have a substantial genetic loading for SCZ. The presence of SCZ-like MDD subgroups would be indicated by an interaction between MDD status and polygenic risk of SCZ on cognitive, personality and mood measures. Here, we hypothesized that higher SCZ polygenic risk would define larger MDD case-control differences in cognitive ability, and smaller differences in distress and neuroticism. Polygenic risk scores (PRSs) for SCZ and their association with cognitive variables, neuroticism, mood and psychological distress were estimated in a large population-based cohort (Generation Scotland: Scottish Family Health Study, GS:SFHS). The individuals were divided into those with, and without, depression (n=2587 and n=16 764, respectively) to test for the interactions between MDD status and schizophrenia risk. Replication was sought in UK Biobank (UKB; n=6049 and n=27 476 cases and controls, respectively). In both the cohorts, we found significant interactions between SCZ-PRS and MDD status for measures of psychological distress (ßGS=-0.04, PGS=0.014 and ßUKB=-0.09, PUKB⩽0.001 for GS:SFHS and UKB, respectively) and neuroticism (ßGS=-0.04, PGS=0.002 and ßUKB=-0.06, PUKB=0.023). In both the cohorts, there was a reduction of case-control differences on a background of higher genetic risk of SCZ. These findings suggest that depression on a background of high genetic risk for SCZ may show attenuated associations with distress and neuroticism. This may represent a causally distinct form of MDD more closely related to SCZ.


Assuntos
Transtorno Depressivo Maior/genética , Transtorno Depressivo Maior/psicologia , Predisposição Genética para Doença/genética , Herança Multifatorial/genética , Esquizofrenia/genética , Psicologia do Esquizofrênico , Adulto , Estudos de Casos e Controles , Estudos de Coortes , Feminino , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Neuroticismo , Polimorfismo de Nucleotídeo Único/genética , Medição de Risco , Escócia , Estatística como Assunto , Temperamento
9.
Psychol Med ; 46(11): 2351-61, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27282778

RESUMO

BACKGROUND: Previous neuroimaging studies indicate abnormalities in cortico-limbic circuitry in mood disorder. Here we employ prospective longitudinal voxel-based morphometry to examine the trajectory of these abnormalities during early stages of illness development. METHOD: Unaffected individuals (16-25 years) at high and low familial risk of mood disorder underwent structural brain imaging on two occasions 2 years apart. Further clinical assessment was conducted 2 years after the second scan (time 3). Clinical outcome data at time 3 was used to categorize individuals: (i) healthy controls ('low risk', n = 48); (ii) high-risk individuals who remained well (HR well, n = 53); and (iii) high-risk individuals who developed a major depressive disorder (HR MDD, n = 30). Groups were compared using longitudinal voxel-based morphometry. We also examined whether progress to illness was associated with changes in other potential risk markers (personality traits, symptoms scores and baseline measures of childhood trauma), and whether any changes in brain structure could be indexed using these measures. RESULTS: Significant decreases in right amygdala grey matter were found in HR MDD v. controls (p = 0.001) and v. HR well (p = 0.005). This structural change was not related to measures of childhood trauma, symptom severity or measures of sub-diagnostic anxiety, neuroticism or extraversion, although cross-sectionally these measures significantly differentiated the groups at baseline. CONCLUSIONS: These longitudinal findings implicate structural amygdala changes in the neurobiology of mood disorder. They also provide a potential biomarker for risk stratification capturing additional information beyond clinically ascertained measures.


Assuntos
Tonsila do Cerebelo/patologia , Transtorno Depressivo Maior/patologia , Predisposição Genética para Doença , Substância Cinzenta/patologia , Adolescente , Adulto , Tonsila do Cerebelo/diagnóstico por imagem , Transtorno Depressivo Maior/diagnóstico por imagem , Substância Cinzenta/diagnóstico por imagem , Humanos , Estudos Longitudinais , Risco , Adulto Jovem
10.
Schizophr Res ; 175(1-3): 42-47, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27179666

RESUMO

BACKGROUND: There is an established link between childhood adversity (CA) and schizophrenia. Hippocampus and amygdala abnormalities pre-date onset in those at high familial risk (fHR) of schizophrenia, but it is not clear whether these alterations are associated with CA in those at elevated risk of schizophrenia. METHODS: We examined hippocampal and amygdala volumes in those at fHR who had been referred to a social worker or the Children's Panel compared to those who had not. RESULTS: The right hippocampus and left amygdala were significantly smaller in those that had been referred to social work and Children's Panel. CONCLUSIONS: Our findings suggest that CA can influence structural changes in the brain in a cohort at fHR of schizophrenia. These findings provide further evidence that while genetic factors contribute to the structural changes found in schizophrenia, environmental factors such as CA can have a lasting impact on specific brain regions.


Assuntos
Adultos Sobreviventes de Eventos Adversos na Infância , Tonsila do Cerebelo/diagnóstico por imagem , Predisposição Genética para Doença , Hipocampo/diagnóstico por imagem , Esquizofrenia/genética , Estresse Psicológico/diagnóstico por imagem , Adultos Sobreviventes de Eventos Adversos na Infância/psicologia , Família , Feminino , Lateralidade Funcional , Humanos , Processamento de Imagem Assistida por Computador , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Tamanho do Órgão , Estudos Prospectivos , Esquizofrenia/diagnóstico por imagem , Serviço Social , Estresse Psicológico/genética , Adulto Jovem
12.
Genes Brain Behav ; 15(2): 221-30, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26586578

RESUMO

Brain-derived neurotrophic factor (BDNF) signaling is implicated in the etiology of many psychiatric disorders associated with altered emotional processing. Altered peripheral (plasma) BDNF levels have been proposed as a biomarker for neuropsychiatric disease risk in humans. However, the relationship between peripheral and central BDNF levels and emotional brain activation is unknown. We used heterozygous BDNF knockdown rats (BDNF(+/-)) to examine the effects of genetic variation in the BDNF gene on peripheral and central BDNF levels and emotional brain activation as assessed by awake functional magnetic resonance imaging (fMRI). BDNF(+/-) and control rats were trained to associate a flashing light (conditioned stimulus; CS) with foot-shock, and brain activation in response to the CS was measured 24 h later in awake rats using fMRI. Central and peripheral BDNF levels were decreased in BDNF(+/-) rats compared with control rats. Activation of fear circuitry (amygdala, periaqueductal gray, granular insular) was seen in control animals; however, activation of this circuitry was absent in BDNF(+/-) animals. Behavioral experiments confirmed impaired conditioned fear responses in BDNF(+/-) rats, despite intact innate fear responses. These data confirm a positive correlation [r = 0.86, 95% confidence interval (0.55, 0.96); P = 0.0004] between peripheral and central BDNF levels and indicate a functional relationship between BDNF levels and emotional brain activation as assessed by fMRI. The results demonstrate the use of rodent fMRI as a sensitive tool for measuring brain function in preclinical translational studies using genetically modified rats and support the use of peripheral BDNF as a biomarker of central affective processing.


Assuntos
Fator Neurotrófico Derivado do Encéfalo/metabolismo , Condicionamento Psicológico/fisiologia , Medo/fisiologia , Aprendizagem/fisiologia , Imageamento por Ressonância Magnética , Tonsila do Cerebelo/metabolismo , Animais , Fator Neurotrófico Derivado do Encéfalo/genética , Condicionamento Clássico/fisiologia , Feminino , Imageamento por Ressonância Magnética/métodos , Masculino , Estimulação Luminosa/métodos , Ratos Transgênicos , Vigília
13.
Schizophr Res ; 173(3): 146-151, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-25534070

RESUMO

Schizophrenia is associated with structural brain abnormalities that are likely to be present before disease onset. It remains unclear to what extent these represent general vulnerability indicators or are associated with the developing clinical state itself. It also remains unclear whether such state or trait alterations may be evident at any given time-point, or whether they progress over time. To investigate this, structural brain scans were acquired at two time-points (mean scan-interval 1.87years) in a cohort of young unaffected individuals at high familial risk of schizophrenia (baseline, n=142; follow-up, n=64) and healthy controls (baseline, n=36; follow-up, n=18). Sub-cortical reconstructions of the hippocampus and amygdala were generated using the longitudinal pipeline available with Freesurfer. The high risk cohort was subdivided into individuals that remained well during the study (HR[well], baseline, n=68; follow-up, n=30), transient and/or partial symptoms that were insufficient to support a formal diagnosis (HR[symp], baseline, n=57; follow-up, n=26) and individuals that subsequently developed schizophrenia according to ICD-10 criteria (HR[ill], baseline, n=17; follow-up, n=8). Longitudinal change in the hippocampus and amygdala was compared, focusing first on overall differences between high-risk individuals and controls and then on sub-group differences within the high-risk cohort. We found a significantly altered developmental trajectory for all high risk individuals compared to controls, with controls showing a significant increase in hippocampal volume over time compared to those at high risk. We did not find evidence of altered longitudinal trajectories based on clinical outcome within the high risk cohort. These results suggest that an altered developmental trajectory of hippocampal volume is associated with a general familial predisposition to develop schizophrenia, as this alteration was not related to subsequent clinical outcome.


Assuntos
Hipocampo/diagnóstico por imagem , Esquizofrenia/diagnóstico por imagem , Adolescente , Adulto , Idoso , Envelhecimento/patologia , Tonsila do Cerebelo/diagnóstico por imagem , Corpo Estriado/diagnóstico por imagem , Feminino , Seguimentos , Predisposição Genética para Doença , Humanos , Modelos Lineares , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Risco , Tálamo/diagnóstico por imagem , Adulto Jovem
14.
Psychol Med ; 46(4): 891-6, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26654172

RESUMO

BACKGROUND: There is now a well-established link between childhood adversity (CA) and schizophrenia. Similar structural abnormalities to those found in schizophrenia including alterations in grey-matter volume have also been shown in those who experience CA. METHOD: We examined whether global estimates of cortical thickness or surface area were altered in those familial high-risk subjects who had been referred to a social worker or the Children's Panel compared to those who had not. RESULTS: We found that the cortical surface area of those who were referred to the Children's Panel was significantly smaller than those who had not been referred, but cortical thickness was not significantly altered. There was also an effect of social work referral on cortical surface area but not on thickness. CONCLUSIONS: Cortical surface area increases post-natally more than cortical thickness. Our findings suggest that CA can influence structural changes in the brain and it is likely to have a greater impact on cortical surface area than on cortical thickness.


Assuntos
Adultos Sobreviventes de Eventos Adversos na Infância , Córtex Cerebral/patologia , Substância Cinzenta/patologia , Esquizofrenia/patologia , Adolescente , Adulto , Córtex Cerebral/diagnóstico por imagem , Feminino , Predisposição Genética para Doença , Substância Cinzenta/diagnóstico por imagem , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Tamanho do Órgão , Risco , Esquizofrenia/diagnóstico por imagem , Esquizofrenia/genética , Adulto Jovem
15.
Psychol Med ; 45(15): 3317-27, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26189425

RESUMO

BACKGROUND: Neurocognitive performance deficits have been observed in mood disorder patients and their unaffected relatives and may therefore qualify as endophenotypes. However, the precise time course of neurocognitive deficits has not been studied so that it is unknown whether neurocognitive abnormalities reflect the early effects of familial vulnerability to mood disorders or if they emerge at illness onset. METHOD: A neuropsychological test battery was administered at baseline and after a 2-year follow-up interval in 111 initially unaffected young adults at high familial risk of mood disorders and 93 healthy controls (HC). During the follow-up period, 20 high-risk subjects developed major depressive disorder (HR-MDD), with the remainder remaining well (HR-well). Linear mixed-effects models were used to investigate differences and longitudinal changes in the domains of attentional processing, working memory, verbal learning and memory, and cognitive flexibility. RESULTS: Reduced long delay verbal memory and extradimensional set-shifting performance across both time points were found in the HR-well group relative to controls. The HR-MDD group displayed decreased extradimensional set-shifting abilities across both time points as compared with the HC group only. There were no significant performance differences between the two high-risk groups. CONCLUSIONS: Reduced verbal memory and cognitive flexibility are familial trait markers for vulnerability to mood disorders in individuals with a close family history of bipolar disorder. Both neurocognitive performance deficits appear to be relatively stable over a 2-year time period and do not appear to be linked to the onset of MDD. These findings support their use as stable quantitative endophenotypes for mood disorders.


Assuntos
Transtorno Bipolar/complicações , Transtornos Cognitivos/etiologia , Transtorno Depressivo Maior/complicações , Endofenótipos , Predisposição Genética para Doença , Adulto , Feminino , Seguimentos , Humanos , Masculino , Risco , Adulto Jovem
16.
Psychol Med ; 45(6): 1207-18, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25229638

RESUMO

BACKGROUND: Abnormalities of emotion-related brain circuitry, including cortico-thalamic-limbic regions underpin core symptoms of bipolar disorder (BD) and major depressive disorder (MDD). It is unclear whether these abnormalities relate to symptoms of the disorder, are present in unaffected relatives, or whether they can predict future illness. METHOD: The Bipolar Family Study (BFS) is a prospective longitudinal study that has examined individuals at familial risk of mood disorder and healthy controls on three occasions, 2 years apart. The current study concerns imaging data from the second assessment; 51 controls and 81 high-risk (HR) individuals performing an emotional memory task. The latter group was divided into 61 HR individuals who were well, and 20 who met diagnostic criteria for MDD. At the time of the third assessment a further 11 HR individuals (from the Well group) had developed MDD. The current analyses focused on (i) differences between groups based on diagnostic status at the time of the scan, and (ii) predictors of future illness, comparing the 11 HR individuals who became unwell after the second scanning assessment to those who remained well. RESULTS: All groups demonstrated typical emotional modulation of memory and associated brain activations. For analysis (i) the HR MDD group demonstrated increased thalamic activation v. HR Well. (ii) HR Well individuals who subsequently became ill showed increased activation of thalamus, insula and anterior cingulate compared to those who remained well. CONCLUSIONS: These findings suggest evidence for specific changes related to the presence of illness and evidence that changes in brain function in cortico-thalamic-limbic regions precede clinical illness.


Assuntos
Córtex Cerebral/fisiopatologia , Transtorno Depressivo Maior/fisiopatologia , Emoções/fisiologia , Tálamo/fisiopatologia , Adulto , Transtorno Bipolar/fisiopatologia , Transtorno Depressivo Maior/diagnóstico , Suscetibilidade a Doenças , Feminino , Giro do Cíngulo/fisiopatologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Sintomas Prodrômicos , Prognóstico , Estudos Prospectivos , Risco , Adulto Jovem
17.
J Psychopharmacol ; 29(2): 144-54, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25049260

RESUMO

There is a growing consensus that a symptomatology as complex and heterogeneous as schizophrenia is likely to be produced by widespread perturbations of brain structure, as opposed to isolated deficits in specific brain regions. Structural brain-imaging studies have shown that several features of the brain, such as grey matter, white matter integrity and the morphology of the cortex differ in individuals at high risk of the disorder compared to controls, but to a lesser extent than in patients, suggesting that structural abnormalities may form markers of vulnerability to the disorder. Research has had some success in delineating abnormalities specific to those individuals that transition to psychosis, compared to those at high risk that do not, suggesting that a general risk for the disorder can be distinguished from alterations specific to frank psychosis. In this paper, we review cross-sectional and longitudinal studies of individuals at familial or clinical high risk of the disorder. We conclude that the search for reliable markers of schizophrenia is likely to be enhanced by methods which amalgamate structural neuroimaging data into a coherent framework that takes into account the widespread distribution of brain alterations, and relates this to leading hypotheses of schizophrenia.


Assuntos
Biomarcadores/metabolismo , Suscetibilidade a Doenças/patologia , Esquizofrenia/diagnóstico , Esquizofrenia/patologia , Suscetibilidade a Doenças/metabolismo , Humanos , Imageamento por Ressonância Magnética/métodos , Risco , Esquizofrenia/metabolismo
18.
Transl Psychiatry ; 2: e130, 2012 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-22760554

RESUMO

Genome-wide association studies (GWAS) have demonstrated a significant polygenic contribution to bipolar disorder (BD) where disease risk is determined by the summation of many alleles of small individual magnitude. Modelling polygenic risk scores may be a powerful way of identifying disrupted brain regions whose genetic architecture is related to that of BD. We determined the extent to which common genetic variation underlying risk to BD affected neural activation during an executive processing/language task in individuals at familial risk of BD and healthy controls. Polygenic risk scores were calculated for each individual based on GWAS data from the Psychiatric GWAS Consortium Bipolar Disorder Working Group (PGC-BD) of over 16 000 subjects. The familial group had a significantly higher polygene score than the control group (P=0.04). There were no significant group by polygene interaction effects in terms of association with brain activation. However, we did find that an increasing polygenic risk allele load for BD was associated with increased activation in limbic regions previously implicated in BD, including the anterior cingulate cortex and amygdala, across both groups. The findings suggest that this novel polygenic approach to examine brain-imaging data may be a useful means of identifying genetically mediated traits mechanistically linked to the aetiology of BD.


Assuntos
Tonsila do Cerebelo/metabolismo , Transtorno Bipolar/genética , Variação Genética , Giro do Cíngulo/metabolismo , Herança Multifatorial , Adulto , Transtorno Bipolar/metabolismo , Estudos de Casos e Controles , Feminino , Variação Genética/fisiologia , Estudo de Associação Genômica Ampla , Humanos , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Polimorfismo de Nucleotídeo Único , Escalas de Graduação Psiquiátrica , Risco
20.
Psychol Med ; 40(11): 1919-29, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20102666

RESUMO

BACKGROUND: Previous behavioural and neuroimaging studies of emotion processing in autistic spectrum disorder (ASD) have focused on the use of facial stimuli. To date, however, no studies have examined emotion processing in autism across a broad range of social signals. METHOD: This study addressed this issue by investigating emotion processing in a group of 23 adults with ASD and 23 age- and gender-matched controls. Recognition of basic emotions ('happiness', 'sadness', 'anger', disgust' and 'fear') was assessed from facial, body movement and vocal stimuli. The ability to make social judgements (such as approachability) from facial stimuli was also investigated. RESULTS: Significant deficits in emotion recognition were found in the ASD group relative to the control group across all stimulus domains (faces, body movements and voices). These deficits were seen across a range of emotions. The ASD group were also impaired in making social judgements compared to the control group and this correlated with impairments in basic emotion recognition. CONCLUSIONS: This study demonstrates that there are significant and broad-ranging deficits in emotion processing in ASD present across a range of stimulus domains and in the auditory and visual modality; they cannot therefore be accounted for simply in terms of impairments in face processing or in the visual modality alone. These results identify a core deficit affecting the processing of a wide range of emotional information in ASD, which contributes to the impairments in social function seen in people with this condition.


Assuntos
Transtornos Globais do Desenvolvimento Infantil/psicologia , Inteligência Emocional , Adulto , Estudos de Casos e Controles , Criança , Transtornos Globais do Desenvolvimento Infantil/fisiopatologia , Cognição , Emoções , Expressão Facial , Feminino , Humanos , Relações Interpessoais , Julgamento , Masculino , Movimento , Fala , Escalas de Wechsler
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