Neuroticism, social network, stressful life events:Association with mood disorders, depressive symptoms and suicidal ideation in a community sample of women

According to the stress-diathesis hypothesis, depression and suicidal behavior may be precipitated by psychosocial stressors in vulnerable individuals. However, risk factors for mental health are often gender-specific. In the present study, we evaluated common risk factors for female depression in association with depressive symptoms and suicidal ideation in a community sample of women. The sample was composed by 415 women evaluated for mood disorders (MDs), depressive symptoms and suicidal ideation by structured interviews and the Beck depression inventory II (BDI II). All women also filled in the Eysenck personality questionnaire to evaluate neuroticism and were interviewed for social contact frequency and stressful life events (SLEs). In the whole sample, 19% of the women satisfied criteria for MD and suicidal ideation was reported by 12% of the women. Though stressful life events, especially personal and interpersonal problems, and poor social network were associated with all the outcome variables (mood disorder, depressive symptomatology and suicidal ideation), neuroticism survived to all multivariate analyses. Social network, together with neuroticism, also showed strong association with depressive severity, independently from current depressive state. Though we were unable to compare women and men, data obtained from the present study suggest that in women neurotic traits are strongly related to depression and suicidal ideation, and potentially mediate reporting of stressful life events and impaired social network. Independently from a current diagnosis of depression, impaired social network increases depressive symptoms in the women

Indication of increased phase coupling between theta and gamma EEG rhythms associated with the experience of auditory verbal hallucinations

Electroencephalographic oscillations, with different spectral contents, recorded in various brain sites are assumed to play an important role in the information processes underlying cognition as well as the abnormal brain functioning observed in nosological entities that affect neuronal connectivity such as schizophrenia. In the present study we investigated the interaction of EEG rhythms during the experience of auditory verbal hallucinations (AVHs). For this purpose we analyzed data obtained from patients suffering from persistent AVHs, focusing on the mode that the phase of theta oscillations modulate the amplitude of the broad gamma EEG oscillations. Our results indicate increased phase coupling between theta and gamma rhythms observed in the left frontotemporal cortices during AVHs, under eyes closed condition. The average differences of theta-gamma coupling between hallucinatory and resting stages in the left temporal area were found to be statistically significant. These results suggest that a theta-gamma interaction may be involved in the production and experience of AVHs in patients suffering from schizophrenia. (C) 2012 Elsevier Ireland Ltd. All rights reserved

COMT Val158Met moderation of stress-induced psychosis

Exposure to stressful life events increases the risk of developing a psychotic disorder. Moreover, increased reactivity to stress seems to represent part of the vulnerability for psychosis. This study aimed to investigate whether a functional polymorphism in the catechol-O-methyltransferase (COMT Val(158)Met) gene moderates the psychosis-inducing effects of stress.status: publishe

Association of <it>RGS4 </it>variants with schizotypy and cognitive endophenotypes at the population level

<p>Abstract</p> <p>Background</p> <p>While association studies on schizophrenia show conflicting results regarding the importance of the regulator of the G-protein signaling 4 (<it>RGS4</it>) gene, recent work suggests that <it>RGS4 </it>may impact on the structural and functional integrity of the prefrontal cortex. We aimed to study associations of common <it>RGS4 </it>variants with prefrontal dependent cognitive performance and schizotypy endophenotypes at the population level.</p> <p>Methods</p> <p>Four <it>RGS4 </it>single nucleotide polymorphisms (SNP1 [rs10917670], SNP4 [rs951436], SNP7 [rs951439], and SNP18 [rs2661319]) and their haplotypes were selected. Their associations with self-rated schizotypy (SPQ), vigilance, verbal, spatial working memory and antisaccade eye performance were tested with regressions in a representative population of 2,243 young male military conscripts.</p> <p>Results</p> <p>SNP4 was associated with negative schizotypy (higher SPQ negative factor for common T allele, p = 0.009; p = 0.031 for differences across genotypes) and a similar trend was seen also for common A allele of SNP18 (p = 0.039 for allele-load model; but p = 0.12 for genotype differences). Haplotype analyses showed a similar pattern with a dose-response for the most common haplotype (GGGG) on the negative schizotypy score with or without adjustment for age, IQ and their interaction (p = 0.011 and p = 0.024, respectively). There was no clear evidence for any association of the <it>RGS4 </it>variants with cognitive endophenotypes, except for an isolated effect of SNP18 on antisaccade error rate (p = 0.028 for allele-load model).</p> <p>Conclusion</p> <p>Common <it>RGS4 </it>variants were associated with negative schizotypal personality traits amongst a large cohort of young healthy individuals. In accordance with recent findings, this may suggest that RGS4 variants impact on the functional integrity of the prefrontal cortex, thus increasing susceptibility for psychotic spectrum disorders.</p

Schizophrenia Candidate Gene ERBB4: Covert Routes of Vulnerability to Psychosis Detected at the Population Level

Prior genetic and functional evidence established ERBB4 as a probable schizophrenia susceptibility gene that may confer risk via modulating brain information processing dependent on the integrity of frontotemporal brain circuitry. Utilizing retrospective data drawn from the cross-sectional population-based Athens Study of Psychosis Proneness and Incidence of Schizophrenia (ASPIS) (n = 1127), we attempted to independently replicate and further extend previous findings by examining the effects of ERBB4 gene variants on 3 broad population based psychosis-related phenotypes: verbal working memory (VWM), trait schizotypy, and stress-induced subclinical psychotic experiences (PE). Three common ERBB4 single nucleotide polymorphisms that were previously associated with schizophrenia and impaired frontotemporal-related information processing (rs7598440, rs839523, and rs707284), their haplotypes, and corresponding diplotypes were tested. VWM performance was significantly associated with rs839523 and rs707284 markers even after correction for multiple testing, thus validating reported findings that have implicated ERBB4 gene variation on working memory. No associations were detected between these ERBB4 variants and trait schizotypy. However, we were able to detect a significant effect of rs7598440 marker on PE expressed under stressful environmental conditions. Combined haplotype analysis of the above 3 markers, identified a "yin-yang" pattern of association, confirmed at the diplotype level. While GGG haplotype homozygotes were associated with "protective" effects on VWM performance and PE, AAA "risk" haplotype carriers were associated with worse VWM performance and simultaneously exhibited significantly elevated PE. This dual, possibly pleiotropic, impact on frontotemporal circuitry and increased sensitivity to psychosocial stress may represent subtle manifestations of ERBB4-related vulnerability to psychosis, expressed at the population level