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Rich-club organization is key to efficient global neuronal signaling and integration of information. Alterations interfere with higher-order cognitive processes, and are common to several psychiatric and neurological conditions. A few studies examining the structural connectome in obsessive–compulsive disorder (OCD) suggest lower efficiency of information transfer across the brain. However, it remains unclear whether this is due to alterations in rich-club organization. In the current study, the structural connectome of 28 unmedicated OCD patients, 8 of their unaffected siblings and 28 healthy controls was reconstructed by means of diffusion-weighted imaging and probabilistic tractography. Topological and weighted measures of rich-club organization and connectivity were computed, alongside global and nodal measures of network integration and segregation. The relationship between clinical scores and network properties was explored. Compared to healthy controls, OCD patients displayed significantly lower topological and weighted rich-club organization, allocating a smaller fraction of all connection weights to the rich-club core. Global clustering coefficient, local efficiency, and clustering of nonrich club nodes were significantly higher in OCD patients. Significant three-group differences emerged, with siblings displaying highest and lowest values in different measures. No significant correlation with any clinical score was found. Our results suggest weaker structural connectivity between rich-club nodes in OCD patients, possibly resulting in lower network integration in favor of higher network segregation. We highlight the need of looking at network-based alterations in brain organization and function when investigating the neurobiological basis of this disorder, and stimulate further research into potential familial protective factors against the development of OCD.

Clinical and neuroimaging data support the idea that schizo-obsessive comorbidity (SOC), similar to obsessivecompulsive disorder (OCD) and schizophrenia (SCZ), may be a distinct brain disorder. In this study, we examined the strength of resting-state functional connectivity (rsFC) between 19 subregions of the default mode network (DMN) and whole brain voxels in 22 patients with SOC features, 20 patients with SCZ alone, 22 patients with OCD, and 22 healthy controls (HC). The main results demonstrated that patients with SOC exhibited the highest rsFC strength within subregions of the DMN and the lowest rsFC strength between the DMN and subregions of the salience network (SN) compared with the other 3 groups. In addition, compared with HCs, all 3 patient groups exhibited increased rsFC between subregions of the DMN and the executive control network (ECN). The SOC and SCZ group both exhibited increased rsFC between subregions of the DMN and the middle temporal gyrus, but the OCD group exhibited decreased rsFC between them. These findings highlight a specific alteration in functional connectivity in the DMN in patients with SOC, and provide new insights into the dysfunctional brain organization of different mental disorders.

ObjectiveIntelligence is a known vulnerability marker in various psychiatric disorders. In eating disorders (ED) intelligence has not been studied thoroughly. Small-scale studies indicate that intelligence levels might be above general population norms, but larger scale studies are lacking. The aim of this study was to determine intellectual functioning in ED patients and associations with severity of the disorder. Methods: Wechsler's Full scale IQ (FSIQ), Verbal IQ (VIQ) and Performance IQ (PIQ) of 703 adolescent and adult ED patients were compared with population norms. Exploratory analyzes were performed on associations between IQ and both somatic severity (BMI and duration of the disorder) and psychological/behavioral severity (Eating Disorder Inventory [EDI-II] ratings) of the ED. Results: Mean IQ's were significantly higher than population means and effect-sizes were small-to-medium (d=.28, .16 and .23 for VIQ, PIQ, and FSIQ). No linear associations between IQ and BMI were found, but the most severely underweight adult anorexia nervosa (AN) patients (BMI 15) had higher VIQ (107.7) than the other adult AN patients (VIQ 102.1). In adult AN patients PIQ was associated with psychological/behavioral severity of the ED. Discussion: Our findings suggest that, in contrast with other severe mental disorders where low intelligence is a risk factor, higher than average intelligence might increase the vulnerability to develop an ED. (c) 2016 Wiley Periodicals, Inc.(Int J Eat Disord 2017; 50:481-489)

ObjectiveIntelligence is a known vulnerability marker in various psychiatric disorders. In eating disorders (ED) intelligence has not been studied thoroughly. Small-scale studies indicate that intelligence levels might be above general population norms, but larger scale studies are lacking. The aim of this study was to determine intellectual functioning in ED patients and associations with severity of the disorder. Methods: Wechsler's Full scale IQ (FSIQ), Verbal IQ (VIQ) and Performance IQ (PIQ) of 703 adolescent and adult ED patients were compared with population norms. Exploratory analyzes were performed on associations between IQ and both somatic severity (BMI and duration of the disorder) and psychological/behavioral severity (Eating Disorder Inventory [EDI-II] ratings) of the ED. Results: Mean IQ's were significantly higher than population means and effect-sizes were small-to-medium (d=.28, .16 and .23 for VIQ, PIQ, and FSIQ). No linear associations between IQ and BMI were found, but the most severely underweight adult anorexia nervosa (AN) patients (BMI 15) had higher VIQ (107.7) than the other adult AN patients (VIQ 102.1). In adult AN patients PIQ was associated with psychological/behavioral severity of the ED. Discussion: Our findings suggest that, in contrast with other severe mental disorders where low intelligence is a risk factor, higher than average intelligence might increase the vulnerability to develop an ED. (c) 2016 Wiley Periodicals, Inc.(Int J Eat Disord 2017; 50:481-489)

Background Genetic factors have been implicated in the development of substance abuse disorders, but the role of pre-existing vulnerability in addiction is still poorly understood. Personality traits of impulsivity and sensation-seeking are highly prevalent in chronic drug users and have been linked with an increased risk for substance abuse. However, it has not been clear whether these personality traits are a cause or an effect of stimulant drug dependence. Method We compared self-reported levels of impulsivity and sensation-seeking between 30 sibling pairs of stimulant-dependent individuals and their biological brothers/sisters who did not have a significant drug-taking history and 30 unrelated, nondrug-taking control volunteers. Results Siblings of chronic stimulant users reported significantly higher levels of trait-impulsivity than control volunteers but did not differ from control volunteers with regard to sensation-seeking traits. Stimulant-dependent individuals reported significantly higher levels of impulsivity and sensation-seeking compared with both their siblings and control volunteers. Conclusions These data indicate that impulsivity is a behavioral endophenotype mediating risk for stimulant dependence that may be exacerbated by chronic drug exposure, whereas abnormal sensation-seeking is more likely to be an effect of stimulant drug abuse.

Schizophrenia is a complex psychiatric disorder strongly associated with substance use disorders. Theoretically, schizophrenia and SUD may share endocannabinoid alterations in the brain reward system. The main endocannabinoids, anandamide, and 2-arachidonoylglycerol, are lipids which bind cannabinoid receptors. Oleoylethanolamide (OEA), a fatty-acid ethanolamide, binds peroxisome proliferator-activated receptors. The endocannabinoid system has been shown to be impaired in schizophrenia, and recently, our group has shown that schizophrenia patients with SUD have elevated peripheral levels of anandamide and OEA that do not normalize after 3-month treatment with quetiapine. Objective For comparative purposes, we aimed to measure endocannabinoids in non-psychosis substance abusers and non-abusing schizophrenia patients. Methods Using liquid chromatography and mass spectrometry, we measured plasma levels of anandamide and OEA in non-psychosis SUD patients, non-abusing schizophrenia patients, and healthy controls. In an open-label manner, all patients received 12-week treatment with quetiapine. Results Anandamide and OEA were reduced in substance abusers without schizophrenia, relative to healthy controls (p

Background The object of this study was to identify temperament patterns in the Finnish population, and to determine the relationship between these profiles and life habits, socioeconomic status, and health. Methods/Principal Findings A cluster analysis of the Temperament and Character Inventory subscales was performed on 3,761 individuals from the Northern Finland Birth Cohort 1966 and replicated on 2,097 individuals from the Cardiovascular Risk in Young Finns study. Clusters were formed using the k-means method and their relationship with 115 variables from the areas of life habits, socioeconomic status and health was examined. Results Four clusters were identified for both genders. Individuals from Cluster I are characterized by high persistence, low extravagance and disorderliness. They have healthy life habits, and lowest scores in most of the measures for psychiatric disorders. Cluster II individuals are characterized by low harm avoidance and high novelty seeking. They report the best physical capacity and highest level of income, but also high rate of divorce, smoking, and alcohol consumption. Individuals from Cluster III are not characterized by any extreme characteristic. Individuals from Cluster IV are characterized by high levels of harm avoidance, low levels of exploratory excitability and attachment, and score the lowest in most measures of health and well-being. Conclusions This study shows that the temperament subscales do not distribute randomly but have an endogenous structure, and that these patterns have strong associations to health, life events, and well-being.