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Alexithymia is a personality trait characterized by difficulties in the experience and cognitive processing of emotions. It is considered a risk factor for a range of psychiatric and neurological disorders. Functional neuroimaging studies investigating the neural correlates of alexithymia have reported inconsistent results. To integrate previous findings, we conducted a parametric coordinate-based meta-analysis including fifteen neuroimaging studies on emotion processing in alexithymia. During the processing of negative emotional stimuli, alexithymia was associated with a diminished response of the amygdala, suggesting decreased attention to such stimuli. Negative stimuli additionally elicited decreased activation in supplementary motor and premotor brain areas and in the dorsomedial prefrontal cortex, possibly underlying poor empathic abilities and difficulties in emotion regulation associated with alexithymia. Positive stimuli elicited decreased activation in the right insula and precuneus, suggesting reduced emotional awareness in alexithymia regarding positive affect. Independent of valence, higher (presumably compensatory) activation was found in the dorsal anterior cingulate possibly indicating increased cognitive demand. These results suggest valence-specific as well as valence-independent effects of alexithymia on the neural processing of emotions. (C) 2013 Elsevier Ltd. All rights reserved.

Neuroticism is a robust personality trait that constitutes a risk factor for mood disorders. Neuroimaging findings related to neuroticism have been inconsistent across studies and hardly integrated in order to construct a model of the underlying neural correlates of neuroticism. The aim of the current meta-analysis was to provide a quantitative summary of the literature, using a parametric coordinate-based meta-analysis (PCM) approach. Data were pooled for emotion processing tasks investigating the contrasts (negative > neutral) and (positive > neutral) to identify brain regions that are consistently associated with neuroticism across studies. Significant negative and positive correlations with neuroticism were found only for the contrast (negative > neutral) after multiple comparisons correction. Differences in brain activation were found to be associated with neuroticism during fear learning, anticipation of aversive stimuli and the processing and regulation of emotion. The relationship between neuroticism and these three psychological processes and their corresponding neural correlates is discussed. Furthermore, the meta-analytic findings are incorporated into a general model of emotion processing in neuroticism. (C) 2013 Elsevier Ltd. All rights reserved.

The potential of noninvasive neurostimulation by repetitive transcranial magnetic stimulation (rTMS) for improving psychiatric disorders has been studied increasingly over the past two decades. This is especially the case for major depression and for auditory-verbal hallucinations in schizophrenia. The present review briefly describes the background of this novel treatment modality and summarizes evidence from clinical trials into the efficacy of rTMS for depression and hallucinations. Evidence for efficacy in depression is stronger than for hallucinations, although a number of studies have reported clinically relevant improvements for hallucinations too. Different stimulation parameters (frequency, duration, location of stimulation) are discussed. There is a paucity of research into other psychiatric disorders, but initial evidence suggests that rTMS may also hold promise for the treatment of negative symptoms in schizophrenia, obsessive compulsive disorder and post-traumatic stress disorder. It can be concluded that rTMS induces alterations in neural networks relevant for psychiatric disorders and that more research is needed to elucidate efficacy and underlying mechanisms of action.

How we perceive emotional signals from our environment depends on our personality. Alexithymia, a personality trait characterized by difficulties in emotion regulation has been linked to aberrant brain activity for visual emotional processing. Whether alexithymia also affects the brain's perception of emotional speech prosody is currently unknown. We used functional magnetic resonance imaging to investigate the impact of alexithymia on hemodynamic activity of three a priori regions of the prosody network: the superior temporal gyrus (STG), the inferior frontal gyrus and the amygdala. Twenty-two subjects performed an explicit task (emotional prosody categorization) and an implicit task (metrical stress evaluation) on the same prosodic stimuli. Irrespective of task, alexithymia was associated with a blunted response of the right STG and the bilateral amygdalae to angry, surprised and neutral prosody. Individuals with difficulty describing feelings deactivated the left STG and the bilateral amygdalae to a lesser extent in response to angry compared with neutral prosody, suggesting that they perceived angry prosody as relatively more salient than neutral prosody. In conclusion, alexithymia may be associated with a generally blunted neural response to speech prosody. Such restricted prosodic processing may contribute to problems in social communication associated with this personality trait.

Models describing the neural correlates of biased emotion processing in depression have focused on increased activation of anterior cingulate and amygdala and decreased activation of striatum and dorsolateral prefrontal cortex. However, neuroimaging studies investigating emotion processing in depression have reported inconsistent results. This meta-analysis integrates these findings and examines whether emotional valence modulates such abnormalities. A systematic literature search identified 26 whole-brain and 18 region-of-interest studies. Peak coordinates and effect sizes were combined in an innovative parametric meta-analysis. Opposing effects were observed in the amygdala, striatum, parahippocampal, cerebellar, fusiform and anterior cingulate cortex, with depressed subjects displaying hyperactivation for negative stimuli and hypoactivation for positive stimuli. Anterior cingulate activity was also modulated by facial versus non-facial stimuli, in addition to emotional valence. Depressed subjects also showed reduced activity in left dorsolateral prefrontal cortex for negative stimuli and increased activity in orbitofrontal cortex for positive stimuli. Emotional valence is a moderator of neural abnormalities in depression, and therefore a critical feature to consider in models of emotional dysfunction in depression. (C) 2012 Elsevier Ltd. All rights reserved.

The experience of childhood maltreatment is related to an increased risk of developing a variety of psychiatric disorders, as well as a change in the structure of the brain. However, not much is known about the neurobiological basis of resilience to childhood maltreatment. This study aims to identify resting-state functional connectivity (RSFC) patterns specific for resilience to childhood maltreatment, focusing on the default mode and salience network and networks seeded from the amygdala and left dorsomedial prefrontal cortex. Resting-state functional MRI scans were obtained in 33 individuals. Seeds in the bilateral amygdala, the dorsal anterior cingulate cortex (dACC), the posterior cingulate cortex and the left dorsomedial prefrontal cortex were defined and used to examine whether resilient individuals differed from vulnerable individuals and healthy controls in RSFC with other brain regions. Within the salience network, the resilient group was associated with increased RSFC between the left dACC and a region containing the bilateral lingual gyrus and the occipital fusiform gyrus compared to both the vulnerable group and the healthy controls. In this study, we found RSFC patterns specific for resilient individuals. Regions that are implicated are related on a functional level to declarative memory and the processing of emotional stimuli. (C) 2013 Elsevier Ltd. All rights reserved.

Neuroticism (N) is believed to reflect a stable disposition involving specific biological and psychological mechanisms that produce its robust association with psychopathology. The nature of these mechanisms remains unclear, however. Based on an extensive review of published evidence, we argue that three interesting leads are emerging. First, N may reflect individual differences in brain circuits involved in perception of and cognitive control over negative stimuli. More specifically, reduced connectivity between the left amygdala and ACC may impair extinction of the amygdala response to anxiety-eliciting stimuli. Second, the neural evidence matches the psychological findings, which associate N with a negative bias in attention, interpretation and recall of information, increased reactivity, and ineffective coping, and is consistent with findings of decreased cardiovascular flexibility. Third, current studies suggest that HPA-axis influences mood independently of N. Strong claims on N's biological basis, however, are not yet justified due to inconsistencies and lack of replication which are in part due to methodological limitations and N's heterogeneity. We discuss potential methodological improvements and substantive directions for future research. (c) 2012 Elsevier Ltd. All rights reserved.

Apathy is a prominent and influential symptom in several neurological and psychiatric disorders, but it also occurs in the healthy population. It has considerable impact on daily life functioning, in clinical as well as healthy samples. Even though cognitive control is thought to be disrupted in people with apathy, the exact neural underpinnings of apathy remain unclear. Because flexible shifting between behaviors (set‐shifting) is crucial for goal‐directed behavior, disruptions in set‐shifting may underlie apathy. In this study, the neural correlates of apathy during set‐shifting were studied in 34 healthy participants with varying levels of apathy, measured by the Apathy Evaluation Scale. During functional MRI scanning participants performed a set‐shifting task, distinguishing between behavioral switches (a change in response to different stimuli), cognitive switches (a change in response rule), and salience decoupling (detecting a change in relevant stimuli). Regression analysis was used to assess the relationship between apathy and brain activation. Results showed that higher apathy scores were related to reduced activation in the medial superior frontal gyrus and cerebellum (Crus I/II) during cognitive set‐shifting, but not behavioral shifting and salience decoupling. No relationship between apathy and accuracy or response time was found. These results support the idea that alterations in the neural basis of cognitive control, especially cognitive set‐shifting, may contribute to apathy. Hum Brain Mapp 38:2722–2733, 2017. © 2017 Wiley Periodicals, Inc.

In preparation for a multicenter randomized controlled trial, a pilot study was conducted investigating the feasibility and acceptance of a shortened version (12 vs. 40 sessions) of an individual metacognitive psychotherapy (Metacognitive Reflection and Insight Therapy [MERIT]). Twelve participants with a diagnosis of schizophrenia were offered 12 sessions of MERIT. Effect sizes were calculated for changes from baseline to treatment end for metacognitive capacity measured by the Metacognition Assessment Scale-Abbreviated. Nine of twelve patients finished treatment. However, nonsignificant moderate to large effect sizes were obtained on the primary outcome measure. This study is among the first to suggest that patients with schizophrenia will accept metacognitive therapy and evidence improvements in metacognitive capacity. Despite limitations typical to a pilot study, including a small sample size and lack of a control group, sufficient evidence of efficacy was obtained to warrant further investigation.

Background Individuals with a psychotic disorder are at an increased risk of becoming victim of a crime or other forms of aggression. Research has revealed several possible risk factors (e.g. impaired social cognition, aggression regulation problems, assertiveness, self-stigma, self-esteem) for victimization in patients with a psychotic disorder. To address these risk factors and prevent victimization, we developed a body-oriented resilience training with elements of kickboxing: BEATVIC. The present study aims to evaluate the effectiveness of the intervention. Methods/Design Seven mental health institutions in the Netherlands will participate in this study. Participants will be randomly assigned to either the BEATVIC training or the control condition: social activation. Follow-ups are at 6, 18 and 30 months. Short term effects on risk factors for victimization will be examined, since these are direct targets of the intervention and are thought to be mediators of victimization, the primary outcome of the intervention. The effect on victimization will be investigated at follow-up. In a subgroup of patients, fMRI scans will be made before and after the intervention period in order to assess potential neural changes associated with the effects of the training. Discussion This study is the first to examine the effectiveness of an intervention targeted at victimization in psychosis. Methodological issues of the study are addressed in the discussion of this paper. Trial registration Current Controlled Trials: ISRCTN21423535 . Retrospectively registered 30-03-2016.

Although deficits in facial affect processing have been reported in schizophrenia as well asin borderline personality disorder (BPD), these disorders have not yet been directly comparedon facial affect labeling. Using degraded stimuli portraying neutral, angry, fearful andangry facial expressions, we hypothesized more errors in labeling negative facial expressionsin patients with schizophrenia compared to healthy controls. Patients with BPD wereexpected to have difficulty in labeling neutral expressions and to display a bias towards anegative attribution when wrongly labeling neutral faces. Patients with schizophrenia (N =57) and patients with BPD (N = 30) were compared to patients with somatoform disorder(SoD, a psychiatric control group; N = 25) and healthy control participants (N = 41) on facialaffect labeling accuracy and type of misattributions. Patients with schizophrenia showeddeficits in labeling angry and fearful expressions compared to the healthy control group andpatients with BPD showed deficits in labeling neutral expressions compared to the healthycontrol group. Schizophrenia and BPD patients did not differ significantly from each otherwhen labeling any of the facial expressions. Compared to SoD patients, schizophreniapatients showed deficits on fearful expressions, but BPD did not significantly differ fromSoD patients on any of the facial expressions. With respect to the type of misattributions,BPD patients mistook neutral expressions more often for fearful expressions compared toschizophrenia patients and healthy controls, and less often for happy compared to schizophreniapatients. These findings suggest that although schizophrenia and BPD patientsdemonstrate different as well as similar facial affect labeling deficits, BPD may be associatedwith a tendency to detect negative affect in neutral expressions.

The current exploratory study examined the associations between auditory vocal hallucinations (AVH) and delusions and religiosity in young adolescents. 337 children from a population-based case-control study with and without AVH, were assessed after five years at age 12 and 13, on the presence and appraisal of AVH, delusions and religiosity. AVH status (persistent, remittent, incident or control) was examined in relationship to religiosity. Results demonstrated a non-linear association between AVH and religiosity. Moderately religious adolescents were more likely to report AVH than non-religious adolescents (O.R.=2.6). Prospectively, moderately religious adolescents were more likely to have recently developed AVH than non-religious adolescents (O.R.=3.6) and strongly religious adolescents (O.R=7.9). Of the adolescents reporting voices in this sample (163%), more than half reported positive voices. Religious beliefs were often described as supportive, useful or neutral (82%), regardless of the level of religiosity, for both adolescents with and without AVH. Co-occurrence of AVH and delusions, and severity of AVH were not related to religiosity. The present findings suggest there may be a non-linear association between religiosity and hearing voices in young adolescents. A speculative explanation may be that religious practices were adopted in response to AVH as a method of coping. (C) 2015 Elsevier Ireland Ltd. All rights reserved.

H-Magnetic Resonance Spectroscopy (1H-MRS) can offer insights in various neuropathologies by measuring metabolite levels in the brain. In the current study we investigated the levels of glutamate + glutamine (Glx, neurotransmitter and precursor) and N-Acetyl Aspartate + glutamic acid (NAA + NAAG; neuronal viability) in the prefrontal cortex of patients with a psychotic disorder and people at Ultra High Risk (UHR) for psychosis. A 1H-MRS spectrum was acquired in 31 patients with a recent onset psychotic disorder and 60 with a chronic state, 16 UHR patients and 36 healthy controls. Absolute metabolite levels were calculated using LCModel with a reference water peak. Groups were compared while taking into account age and partial volume effects. Moreover, we investigated associations with positive and negative symptoms, duration of illness and antipsychotic treatment in patients. The most notable finding is that chronicity of schizophrenia was related to decreased levels of Glx and NAA. On the other hand, although on an exploratory note, UHR showed increased levels of prefrontal Glx and NAA levels with increasing age. Our results may indicate an initial Glx and NAA increase and subsequent decrease during illness progression that may be related to the neurotoxic effects of glutamate.

Low levels of insulin-like growth factor-1 (IGF-1), an essential neurotrophic factor, have been associated with worse cognitive function in older adults. However, few studies have assessed the prospective association of serum IGF-1 with cognitive function. We aimed to determine the association between serum IGF-1 on concurrent and prospective cognitive function in a population sample of men aged 40-80 years. Blood samples were assessed for IGF-1 levels at baseline and neuropsychological assessments were performed at baseline (n = 400) and at follow-up after a mean duration of 8.3 years (n = 286). Linear regression analyses were carried out to determine the associations between quintiles of IGF-1 and cognitive function at the baseline and follow-up visits. Results showed that those in the top quintile of IGF-1 had lower processing capacity and global cognition scores at follow-up after controlling for cognitive function at baseline and other confounding factors. Additional analyses exploring associations with IGF-1 separately in middle-aged and older participants, and with quartiles of IGF-1 produced similar results. In those older than 60 years, high IGF-1 levels were also associated with lower baseline processing capacity. These results suggest that high IGF-1 levels are associated with worse long-term cognition in men. Together with past studies, we suggest that both, high and low levels of IGF-1 may be associated with poor cognitive function and that optimum levels of IGF-1 (quintile 2 and 3 in current study) may be associated with better cognitive function.

Klinefelter syndrome (KS) is a chromosomal condition (47, XXY) that may help us to unravel gene-brain behavior pathways to psychopathology. The phenotype includes social cognitive impairments and increased risk for autism traits. We used functional MRI to study neural mechanisms underlying social information processing. Eighteen nonclinical controls and thirteen men with XXY were scanned during judgments of faces with regard to trustworthiness and age. While judging faces as untrustworthy in comparison to trustworthy, men with XXY displayed less activation than controls in (i) the amygdala, which plays a key role in screening information for socio-emotional significance, (ii) the insula, which plays a role in subjective emotional experience, as well as (iii) the fusiform gyrus and (iv) the superior temporal sulcus, which are both involved in the perceptual processing of faces and which were also less involved during age judgments in men with XXY. This is the first study showing that KS can be associated with reduced involvement of the neural network subserving social cognition. Studying KS may increase our understanding of the genetic and hormonal basis of neural dysfunctions contributing to abnormalities in social cognition and behavior, which are considered core abnormalities in psychiatric disorders such as autism and schizophrenia.

Alexithymia is a trait characterized by a diminished capacity to describe and distinguish emotions and to fantasize; it is associated with reduced introspection and problems in emotion processing. The default mode network (DMN) is a network of brain areas that is normally active during rest and involved in emotion processing and self-referential mental activity, including introspection. We hypothesized that connectivity of the DMN might be altered in alexithymia. Twenty alexithymic and 18 non-alexithymic healthy volunteers underwent a resting state fMRI scan. Independent component analysis was used to identify the DMN. Differences in connectivity strength were compared between groups. Within the DMN, alexithymic participants showed lower connectivity within areas of the DMN (medial frontal and temporal areas) as compared to non-alexithymic participants. In contrast, connectivity in the high-alexithymic participants was higher for the sensorimotor cortex, occipital areas and right lateral frontal cortex than in the low-alexithymic participants. These results suggest a diminished connectivity within the DMN of alexithymic participants, in brain areas that may also be involved in emotional awareness and self-referential processing. On the other hand, alexithymia was associated with stronger functional connections of the DMN with brain areas involved in sensory input and control of emotion.

While the majority of cognitive studies on auditory hallucinations (AHs) have been conducted in schizophrenia (SZ), an increasing number of researchers are turning their attention to different clinical and nonclinical populations, often using SZ findings as a model for research. Recent advances derived from SZ studies can therefore be utilized to make substantial progress on AH research in other groups. The objectives of this article were to (1) present an up-to-date review regarding the cognitive mechanisms of AHs in SZ, (2) review findings from cognitive research conducted in other clinical and nonclinical groups, and (3) integrate these recent findings into a cohesive framework. First, SZ studies show that the cognitive underpinnings of AHs include self-source-monitoring deficits and executive and inhibitory control dysfunctions as well as distortions in top-down mechanisms, perceptual and linguistic processes, and emotional factors. Second, consistent with SZ studies, findings in other population groups point to the role of top-down processing, abnormalities in executive inhibition, and negative emotions. Finally, we put forward an integrated model of AHs that incorporates the above findings. We suggest that AHs arise from an interaction between abnormal neural activation patterns that produce salient auditory signals and top-down mechanisms that include signal detection errors, executive and inhibition deficits, a tapestry of expectations and memories, and state characteristics that influence how these experiences are interpreted. Emotional factors play a particular prominent role at all levels of this hierarchy. Our model is distinctively powerful in explaining a range of phenomenological characteristics of AH across a spectrum of disorders.

This article presents a report on the first meeting of the International Consortium on Hallucination Research, which took place on September 13-14, 2011 at the Institute of Psychiatry, London. The first day of the meeting served to reflect on the current state of knowledge regarding auditory hallucinations in different diagnostic groups, based on the presentations from the phenomenology, cognition, emotion, electrophysiology, neurochemical, neuroimaging, genetics, treatment, and computational modeling working groups. The second day comprised a discussion forum where the most important and urgent questions for future research were identified. The meeting recognized that a lot has been achieved in auditory hallucination research but that much still remains to be done. Here, we outline the top 16 goals for research on auditory hallucinations, which cover topics of conceptual importance, academic and treatment issues, scientific rigor, and cross-disciplinary collaboration. Concerted and coordinated actions will be required to make substantial research progress.

Among the general population, individuals with subthreshold psychotic-like experiences, or psychosis proneness (PP), can be psychometrically identified and are thought to have a 10-fold increased risk of psychosis. They also show impairments in measures of emotional functioning parallel to schizophrenia. Whilst previous studies have revealed altered brain activation in patients with schizophrenia during emotional processing, it is unclear whether these alterations are also expressed in individuals with high PP. Here we used Support Vector Machine (SVM) to perform multivariate pattern classification based on brain activation during emotional processing in 20 individuals with high PP and 20 comparison subjects (low PP). In addition, we performed a standard univariate analysis based on the General Linear Model (GLM) on the same data for comparison. The experimental task involved passively viewing negative and neutral pictures from the International Affective Picture System (lAPS). SVM allowed classification of the two groups with statistically significant accuracy (p = 0.017) and identified group differences within an emotional circuitry including the amygdala, insula, anterior cingulate and medial prefrontal cortex. In contrast, the standard univariate analysis did not detect any significant between-group differences. Our results reveal a distributed and subtle set of alterations in brain function within the emotional circuitry of individuals with high PP, providing neurobiological support for the notion of dysfunctional emotional circuitry in this group. In addition, these alterations are best detected using a multivariate approach rather than standard univariate methods. Further application of this approach may aid in characterising people at clinical and genetic risk of developing psychosis. (C) 2011 Elsevier Inc. All rights reserved.

Background: Individuals who have a psychotic disorder often fnd it dif-fcult to recognize emotions, read others' mental states, and assess social situations. These social cognitive defcits are highly predictive of problems in daily life functioning. Meta-analyses show that social cognition can be improved by social cognition training (SCT) approaches; however, long-term effects appear to be limited. Given that training of cognitive functions is best executed in a manner that resembles and is integrated with participants' daily lives as much as possible, a plausible explanation is that the stimuli and techniques that are typically used in SCT do not suffciently resemble real-life social interactions. Several key characteristics of real-world interactions are absent from these stimuli, most notably interaction with the material. Methods: To improve transference of SCT to daily life functioning and interaction, we have therefore developed a SCT which utilizes Virtual Reality (VR). VR is highly realistic, eliciting genuine psychological reac-tions, and highly interactive: the environment and the virtual people (“avatars”) in it react to the actions of the participant. At the same time, VR is customizable and controllable, allowing for training that is tailored to the individual. Results: A new form of SCT, utilizing VR (called “DiSCoVR”), has been developed. DiSCoVR consists of 16 sessions, provided over the course of 8 weeks, in which the following social cognitive domains are trained: (1) Emotion perception; (2) Social perception and Theory of Mind (ie, understanding the context and interdependence of emotions, thoughts and behavior); and (3) Social interaction training (ie, understanding the other person and choosing an adequate response). These domains are trained in VR, supplemented by coaching from a therapist, and homework assignments. DiSCoVR is currently being piloted amongst 25 mental health service clients and 25 healthy controls in the northern Netherlands. In this pilot, we primarily test the acceptability and feasibility of the intervention. Furthermore, effects of the intervention on several domains of social cognition are investigated. Moreover, social behavior in VR is studied using heart rate and eye tracking data, comparing healthy controls and clients. Conclusion: We will present a theoretical framework for DiSCoVR. Moreover, we will demonstrate the intervention and provide preliminary results of the ongoing pilot study.

Novel strategies are needed in the treatment of hallucinations as a subgroup of patients with pathological hallucinations (>30%) do not respond to antipsychotics or are not compliant with medication. We review recently developed biological and cognitive treatments. Repetitive transcranial magnetic stimulation concerns neuromodulation targeted at aberrant activity in regions shown to be hyperactive in neuroimaging studies. Repetitive transcranial magnetic stimulation has been shown to reduce auditory hallucinations in several studies. However, not all studies have confirmed such effects, and a number of questions remain. With regard to cognitive therapeutic approaches, new proposals include attention training, acceptance and commitment therapy, and competitive memory training. After a brief discussion of these approaches, we take stock of recent advances and discuss avenues for future research.

Objective: To investigate the multifactorial relationship between illness insight, cognitive and emotional processes, and illness characteristics in bipolar disorder patients. Methods: Data from 85 euthymic or mildly to moderately depressed bipolar disorder patients were evaluated. Insight was measured using the Mood Disorder Insight Scale (total score and subscale scores: awareness of illness, symptom attribution, and need for treatment). Cognitive and emotional functioning was measured in four domains (processing speed, memory, executive functioning, and emotional learning) in addition to premorbid IQ. Illness characteristics were assessed using the Mini-International Neuropsychiatric Interview, the Questionnaire for Bipolar Disorder, and the Inventory of Depressive Symptomatology-self rating scale. Regression analyses were performed for the whole sample. Post-hoc, interactions with lifetime psychotic features (LPF) were statistically tested and if significant, analyses were repeated for patients with (n = 36) and without (n = 49) LPF separately. Results: In the whole group, better insight was associated with lower processing speed, better memory performance, increased emotional learning, higher level of depressive symptoms, and longer duration of illness. Patients with LPF had worse awareness of illness, but better symptom attribution than patients without LPF. No group differences for need for treatment and overall insight were found. Finally, processing speed significantly predicted subscores for symptom attribution in patients with LPF only. Conclusions: Cognitive functioning as well as impairments in emotional learning and psychotic features independently contributes to impaired insight in bipolar disorder. Processing speed seems to be a key variable in the prediction of insight in patients with LPF and not in patients without LPF.

The Health Council of the Netherlands (HCN) and other organisations hold the basic assumption that induced electric current and the generation and absorption of heat in biological material caused by radiofrequency electromagnetic fields are the only causal effects with possible adverse consequences for human health that have been scientifically established to date. Hence, the exposure guidelines for the 10 MHz-10 GHz frequency range are based on avoiding adverse effects of increased temperatures that may occur of the entire human body at a specific absorption rate (SAR) level above 4 W/kg.During the workshop on Thermal Aspects of Radio Frequency Exposure on 11-12 January 2010 in Gaithersburg, Maryland, USA, the question was raised whether there would be a practical advantage in shifting from expressing the exposure limits in SAR to expressing them in terms of a maximum allowable temperature increase. This would mean defining adverse time-temperature thresholds. In this paper, the HCN discusses the need for this, considering six points: consistency, applicability, quantification, causality, comprehensibility and acceptability.The HCN concludes that it seems unlikely that a change of dosimetric quantity will help us forward in the discussion on the scientific controversies regarding the existence or non-existence of non-thermal effects in humans following long duration, low intensity exposure to electromagnetic fields. Therefore, the HCN favours maintaining the current approach of basic restrictions and reference levels being expressed as SAR and in V/m or µT, respectively.Read More: http://informahealthcare.com/doi/abs/10.3109/02656736.2010.534528

Studies of individuals at ultra high risk (UHR) for psychosis have revealed deviations in cognitive and neural development before the onset of psychosis. As affective impairments are among the core dysfunctions in psychotic disorders such as schizophrenia, this study assessed emotion processing and the relationship with social competence in adolescents at risk for psychosis. Thirty-four adolescents at UHR for psychosis and twenty-three non-clinical controls completed the Bermond-Vorst Alexithymia Questionnaire, a measure of emotion awareness. Social inadequacy was measured using the Dutch Personality Questionnaire. Schizophrenia spectrum psychopathology was assessed using self-report and clinical instruments. The Wechsler Adult Intelligence Scale (WAIS) was used to evaluate intellectual functioning. UHR adolescents showed difficulties in identifying and verbalizing their own emotions, independent of intelligence scores. Emotion awareness problems were related to social inadequacy and schizotypal traits in the high risk group. These findings suggest that UHR adolescents may have reduced emotion awareness, independent of intellectual functioning. The relationship with social inadequate behavior fits with the idea that emotion awareness is a prerequisite for the regulation of emotions in social contexts. In the search for early vulnerability markers of risk for psychosis, studying emotion processing besides cognitive abilities might increase our understanding of 'at risk' developmental pathways. (C) 2010 Elsevier Ireland Ltd. All rights reserved.

Introduction: Negative symptoms of schizophrenia often predict an unfavorable clinical outcome. Disturbed dopamine transmission in different brain parts may underlie different aspects of negative symptoms, and the effect of antipsychotics on them may also differ. This pilot study investigated the potentially therapeutic effects of the partial dopamine agonist aripiprazole on different negative symptoms.Methods: This pilot study randomly assigned patients with schizophrenia (N=40) to either aripiprazole or risperidone. After 6 weeks of treatment, the severity of negative symptoms was determined by the PANSS. Subscales of self-report questionnaires were used to assess differences in initiative, anhedonia, social functioning and subjective well-being.Results: Patients treated with aripiprazole showed a significant improvement on measures for anhedonia and subjective wellbeing. Negative symptoms in general, lack of initiative and social inhibition were also lower in the aripiprazole treated group, but without reaching statistical significance.Discussion: According to this pilot study, aripiprazole appears to specifically improve anhedonia and subjective wellbeing compared to risperidone. This may be caused by a specific effect of aripiprazole on the limbic branch of the dopamine system. Future studies should replicate this finding with a larger sample size.

Objective: Major depressive disorder (MDD) has been associated with executive dysfunction and related abnormal prefrontal activity, whereas the status of executive function (EF) in frequently co-occurring anxiety disorders and in comorbid depression-anxiety is unclear. We aimed to study functional MRI correlates of (visuospatial) planning in MDD and anxiety disorders and to test for the effects of their comorbidity. Method: Functional MRI was employed during performance of a parametric Tower of London task in out-patients with MDD (n = 65), MDD with comorbid anxiety (n = 82) or anxiety disorders without MDD (n = 64), and controls (n = 63). Results: Moderately/severely depressed patients with MDD showed increased left dorsolateral prefrontal activity as a function of task load, together with subtle slowing during task execution. In mildly depressed and remitted MDD patients, in anxiety patients, and in patients with comorbid depression-anxiety, task performance was normal and no activation differences were observed. Medication use and regional brain volume were not associated with altered visuospatial planning. Conclusion: Prefrontal hyperactivation during high planning demands is not a trait characteristic, but a state characteristic of MDD without comorbid anxiety, occurring independent of SSRI use. Disturbances in planning or the related activation are probably not a feature of anxiety disorders with or without comorbid MDD, supporting the current distinction between anxiety disorders and depression.

Genetic variation in the catechol-O-methyltransferase (COMT) Val158Met polymorphism has been shown to influence performance on cognitive and emotional tasks. Specifically, it has been suggested that the Met allele might be less advantageous than the Val allele with respect to emotional processing.This study addresses the question whether the presence of the Met allele is directly related to both lower emotional verbalizing proficiency and differences in brain activation during emotional processing. Specifically, we investigated whether COMT genotype would be associated with differences in activation in cortical midline structures during valence evaluation of words.Forty participants ranging from low to high on the verbalizing subscale of the Bermond-Vorst Alexithymia Questionnaire (BVAQ) were genotyped for the COMT Val158Met polymorphism. During fMRI, they evaluated the valence of emotional words.Met homozygotes reported more difficulties in verbalizing their feelings. In addition, the Met allele was associated with attenuated brain activation in posterior cingulate gyrus and precuneus during valence evaluation.We conclude that the Met allele modulates neural activation in regions associated with emotional awareness. Our findings may contribute to understanding the neural correlates of susceptibility for affective disorders. (C) 2010 Elsevier Inc. All rights reserved.

BackgroundThe peak in age of onset of psychotic disorders such as schizophrenia during puberty and early adulthood suggests a relationship between the expression of psychopathology and the changes in the brain and body that take place during this dynamic maturational period, including a dramatic increase in circulating oestrogens and androgens. This study examined levels of salivary testosterone and oestradiol in adolescents with prepsychotic, prodromal symptoms, as this may mediate risk for psychosis by having an impact on brain development.MethodIn 21 male adolescents with prodromal symptoms and 21 male non-clinical controls levels of testosterone and oestradiol were measured in saliva. Tanner pubertal stage and prodromal symptoms were also assessed.ResultsLevels of testosterone were significantly lower in adolescents with prodromal symptoms as compared with non-clinical controls. No group differences in oestradiol were found. In the total sample, level of testosterone was significantly correlated with age and Tanner pubertal stage.ConclusionsOur observations are in line with current hypotheses stressing the role of neuroendocrine factors during adolescence in the expression of psychotic symptoms. From a developmental perspective, susceptibility to psychotic disorders increases during adolescence. Our data suggest that testosterone might, in part, mediate this increased vulnerability. Further research is needed to assess the mediating, neural, mechanisms through which testosterone may have an impact on the development of psychotic symptoms. In the search for early risk markers for psychosis, studying neuroendocrine factors might increase our understanding of ‘at-risk’ developmental pathways.

Reduced insight has been reported in a majority of patients with a psychotic disorder. Most studies have focused on associations with neurocognition, neglecting relations with social cognition. Two hundred seventy patients with nonaffective psychosis participated in this study, which was part of the GROUP (Genetic Risk and OUtcome of Psychosis)-project. Linear regression analyses were performed to investigate the predictive value of composite measures of neurocognition, social cognition, and clinical symptoms. The moderating effect of phase of illness was also investigated. Insight was measured with a composite measure, based on the insight item on the Positive And Negative Syndrome Scale (PANSS) and the Birchwood Insight Scale (BIS). Insight on the BIS and the PANSS correlated significantly (r =. 406). All independent variables correlated with the insight composite measure. The additional effect of social cognition and clinical symptoms were both significant. Phase of illness was a moderating variable: In patients with recent-onset psychosis (ROP), none of the independent variables explained variance. In patients with multiple episode or chronic psychosis, both social cognition and clinical symptoms had additional effects and explained insight, along with neurocognition, together explaining 20% of the variance. These findings indicate that multiple factors are associated with insight in psychosis. Specifically, associations of insight with social cognitive and clinical symptom measures were observed, over and above a contribution of neurocognition. This supports theories that imply a role for deficient emotion recognition and mentalizing in reduced insight. Further studies need to investigate insight in ROP into more detail. © 2010 The Author.

The Cortical Mid line Structures (CMS) play a critical role in self-reflection, together with the insula. Abnormalities in self-referential processing and its neural underpinnings have been reported in schizophrenia and at-risk populations, suggesting they might be markers of psychotic vulnerability. Psychometric measures of schizotypal traits may be used to index psychosis proneness (PP) in nonclinical samples. It remains an unresolved question whether differences in self-reflective processing are associated with PP. Method: Six hundred students completed the Community Assessment of Psychic Experiences Questionnaire, positive subscale. Two groups were formed from the extremes of the distribution (total N = 36). fMRI was used to examine CMS/insula function during a self-reflection task. Participants judged personality trait sentences about self and about an acquaintance. Results: High PP subjects attributed less positive traits to others (i.e., acquaintances) than subjects with low PP. Across groups, the contrasts self > semantic and self > other induced activation in CMS and insula, whereas other > semantic did not produce insula activation. Other > self induced posterior cingulate cortex activation in low PP but not in high PP. In addition, high PP subjects showed stronger activation than low PP in left insula during self > semantic. Examining valence effects revealed that high PP individuals showed increased activation in left insula, right dMPFC, and left vMPFC for positive self-related traits, and in bilateral insula, ACC, and right dMPFC for negative self-related traits. Conclusions: The findings suggest that aspects of self-referential processing and underlying brain mechanisms are similar in clinical and subclinical (high PP) forms of psychosis, suggesting that these may be associated with vulnerability to psychosis.

It is time for policy-makers, funders, researchers and clinicians to tackle high suicide rates, say Andre Aleman and Damiaan Denys.

Theories about auditory hallucinations in schizophrenia suggest that these experiences occur because patients fail to recognize thoughts and mental events as self-generated. Different theoretical models have been proposed about the cognitive mechanisms underlying auditory hallucinations. Regardless of the cognitive model being tested, however, experimental designs are almost identical in that they require a judgment regarding whether an action was self-originated or not. The aim of the current study was to integrate all available literature for a meta-analysis on this topic and reach conclusions about self-recognition performance in (1) patients with schizophrenia compared with healthy controls and (2) patients with auditory hallucinations compared with patients without these symptoms. A comprehensive literature review identified 23 studies that contrasted the performance of schizophrenia patients with healthy controls (1370 participants) and 9 studies that directly compared patients with and without auditory hallucinations (315 participants). We found significantly reduced self-recognition performance in schizophrenia patients, which was more pronounced in patients with auditory hallucinations compared with patients without. In patients with hallucinations, this pattern of performance was specific to self-recognition processes and not to the recognition of new external information. A striking finding was the homogeneity in results across studies regardless of the action modality, timing delay, and design used to measure self-recognition. In summary, this review of studies from the last 30 years substantiates the view that self-recognition is impaired in patients with schizophrenia and particularly those with auditory hallucinations. This suggests an association, perhaps a causal one, between such deficit and hallucinatory experiences in schizophrenia.

Theory of mind (TOM) refers to the capacity to infer one's own and other persons' mental states. ToM abilities are compromised in schizophrenia, in association with dysfunctional activity in predominantly prefrontal brain regions. Prior behavioral studies have also suggested ToM deficits in healthy individuals with psychosis proneness (PP), although no study to date had investigated the associated neural mechanisms in such a sample. Here we used functional magnetic resonance imaging (fMRI) to compare brain activation of subjects with high versus low scores on positive-dimension PP and a ToM task. The ToM task involved first and second order attribution of cognitive and affective mental states to a cartoon character based on verbal and eye-gaze cues. No between-group differences were found on behavioral performance. fMRI analyses revealed a group interaction in anterior prefrontal cortex (BA 10), with the high PP group showing significantly more activity thereof, relative to the low PP, during second order mentalizing than during first order mentalizing. Further between-group differences were observed in dorsomedial and lateral prefrontal regions (BA 46/9), with the high PP group also showing greater activation during second order mentalizing. These results suggest that subjects with positive-dimension PP require more activation of prefrontal areas to adequately mentalize. Differences in the neural mechanisms underlying ToM might be associated with vulnerability to psychosis. (C) 2010 Elsevier Ltd. All rights reserved.

Major depressive disorder (MDD) is a common psychiatric disorder and leading cause of disability worldwide. It is associated with increased mortality, especially from suicide. Heritability of MDD is estimated around 40%, suggesting that genotyping is a promising field for research into the development of MDD. According to the dopamine theory of affective disorders, a deficiency in dopaminergic neurotransmission may play a role in the major symptoms of MDD. Specific polymorphisms in genes that affect dopamine transmission could increase susceptibility to MDD. To determine the extent to which these genes influence vulnerability to MDD, we discuss genes for crucial steps in dopamine neurotransmission: synthesis, signalling and inactivation. The val158met polymorphism of the COMT gene exemplifies the lack of consensus in the literature: although it is one of the most reported polymorphisms that relates to MDD vulnerability, its role is not corroborated by meta-analysis. Gene-gene interactions and gene-environment interactions provide more explanatory potential than single gene associations. Two notable exceptions are the DRD4 and DAT gene: both have variable tandem repeat polymorphisms which may have a "single gene" influence on susceptibility to MDD. (C) 2010 Elsevier Ltd. All rights reserved.

BackgroundBy studying behavior, cognitive abilities and brain functioning in adolescents at high risk for psychosis, we can gain an insight into the vulnerability markers or protective factors in the development of psychotic symptoms. Although many high-risk studies have focused on impairments in neurocognitive functions, such as memory and attention, very few studies have investigated problems in processing social cues such as facial expressions as a possible vulnerability marker for psychosis.MethodThirty-six adolescents at ultra-high risk (UHR) for psychosis and 21 non-clinical controls completed a face recognition test, a facial affect labeling test and an inhibitory control test. Schizotypal traits and schizophrenia symptoms were assessed using a schizotypy questionnaire and the Positive and Negative Syndrome Scale (PANSS).ResultsThe UHR group showed impairments in labeling facial expressions of others, in addition to a spared ability to recognize facial identity. More specifically, the UHR group made more errors in labeling neutral expressions compared to the controls, and an analysis of error types indicated that neutral faces were misattributed as being angry. The degree of misattribution of neutral-as-angry faces correlated significantly with reduced inhibitory control.ConclusionsOur findings suggest that misattributing social cues might contribute to vulnerability for psychosis. This social cognitive deficit may be related to problems in inhibitory control, which potentially plays an important role in the selection of appropriate social meaning. These findings may have relevance for understanding the mechanisms underlying prodromal social dysfunction, which should be targeted in future remediation interventions.

Emotion regulation processes, such as reappraisal, are thought to operate through interactions between prefrontal emotion-control regions and subcortical emotion-generation regions such as the amygdala. Impairments in emotional processing and regulation have been reported in schizophrenia and at-risk populations. Psychometric measures may be used to detect vulnerability to schizophrenia in non-clinical samples, or psychosis proneness (PP). It has been shown that individuals with PP have a more than tenfold increased risk of developing a schizophrenia-spectrum disorder. In the present study, we used fMRI to examine the neural dynamics underlying reappraisal in such a sample. 600 undergraduate students completed the Community Assessment of Psychic Experiences Questionnaire (CAPE), positive subscale. Two groups were subsequently formed from the extremes of the distribution (total N = 34). Blood-oxygenated-level-dependent activity elicited with a task involving 3 conditions was analyzed: viewing neutral pictures, viewing negative pictures, and reappraising negative pictures. Subjects reported the strength of experienced negative affect after each trial. Functional connectivity between prefrontal control regions and amygdala was investigated. At the behavioral level, both groups reported successful diminishment of experienced negative emotion. However, high psychosis-prone subjects showed stronger activation than low subjects in a number of prefrontal regions during reappraisal, relative to attending to negative pictures. The amygdala response to negative stimuli was decreased through reappraisal only in the low group. Functional connectivity analysis revealed less prefrontal-amygdala coupling in high psychosis-prone subjects. Thus, reduced cognitive control of emotion at a neural level appeared to be associated with PP. These findings extend the hypothesis of emotion dysregulation in schizophrenia to PP, and suggest that emotion regulation difficulties may be at the core of a vulnerability to psychosis. (C) 2010 Elsevier B.V. All rights reserved.

Background Apathy is a highly debilitating and frequently occurring behavioral characteristic, present in approximately half of the patients with schizophrenia. Apathy is considered a core negative symptom that relates strongest to lack of initiative and is the strongest predictor of poor functional outcome, poor medication compliance, and high caregiver burden. Notwithstanding, measuring apathy is still a challenge. Therefore, we aimed to investigate whether actigraphy, an objective and continuous measurement of activity levels, could yield an objective quantitative measure of apathy severity in schizophrenia patients. Moreover, we aimed to investigate whether actigraphy related to relevant functional neuroimaging underpinnings of apathy, i.e. self-initiated goal-directed behavior. Methods Quantity, variability, and initiation of motor behavior were studied in relation to apathy severity as measured with clinical measures, and in relation to neural correlates of self-initiated behavior using functional Magnetic Resonance Imaging (fMRI). All patients (N=58) suffered from clinical significant apathy, as measured with the Apathy Evaluation Scale and Scale for the Assessment of Negative Symptoms and wore an actigraph for 48 continuous hours. Physical activity was quantified as the total activity counts over the patients’ ten most active hours of each day, summed over two weekend days (Activity-total, i.e. 20 hours in total). Variability of motor behavior (Activity-variability) was calculated by taking the root of the Mean Squared Successive Difference of the activity counts. For 31 of these patients, fMRI data during a task tapping into self-initiative was available. Results Results showed that quantity, variability, and initiation of motor behavior were associated with negative symptoms, but not specifically with apathy. Motor behavior parameters were associated with brain activation during the self-initiative task in various brain regions including inferior parietal regions. The results were only observed during the condition wherein participants were asked to promptly reply to specific cues and not during the condition where more freedom in timing and selection of behavior was allowed. Discussion Actigraphy can be used to measure quantity as well as variability of motor behavior in patients with schizophrenia and with specific relevance for negative symptoms, and that it correlates with selective neural substrates of action selection and activation of motor programs. However, actigraphy may not capture higher-order motivational processes that contribute to apathy severity.

The regulation of negative emotion through reappraisal has been shown to induce increased prefrontal activity and decreased amygdala activity. Individual differences in dispositional mindfulness reflect differences in typical recognition, detachment and regulation of current experience, thought to also operate as top-down control mechanism. We sought to investigate whether such individual differences would be associated with brain activity elicited during reappraisal of negative emotion. Eighteen healthy participants completed a functional magnetic resonance imaging task that involved attending to or reappraising negative stimuli, and provided emotion experience ratings after each trial. Dispositional mindfulness was assessed with a self-report questionnaire. Reappraisal induced activity in a brain network involving predominantly dorsal portions of the prefrontal cortex, replicating previous studies. A voxelwise regression analysis showed that individual differences in the tendency to be mindful predicted activity in neural regions underlying reappraisal, with dorsomedial prefrontal cortex activation increasing with more mindfulness traits. Notably, this prefrontal activation was inversely correlated with the amygdala response to negative scenes, further supporting its role in down-regulating emotion-generation regions. These findings suggest that individual differences in dispositional mindfulness, which reflect the tendency to recognize and regulate current states, may modulate activity in neural systems involved in the effective cognitive control of negative emotion.

Context: Major depressive disorder (MDD), panic disorder, and social anxiety disorder are among the most prevalent and frequently co-occurring psychiatric disorders in adults and may have, at least in part, a common etiology.Objective: To identify the unique and shared neuro-anatomical profile of depression and anxiety, controlling for illness severity, medication use, sex, age of onset, and recurrence.Design: Cross-sectional study.Setting: Netherlands Study of Depression and Anxiety.Participants: Outpatients with MDD (n=68), comorbid MDD and anxiety (n=88), panic disorder, and/or social anxiety disorder without comorbid MDD (n=68) and healthy controls (n=65).Main Outcome Measures: Volumetric magnetic resonance imaging was conducted for voxel-based morphometry analyses. We tested voxelwise for the effects of diagnosis, age at onset, and recurrence on gray matter density. Post hoc, we studied the effects of use of medication, illness severity, and sex.Results: We demonstrated lower gray matter volumes of the rostral anterior cingulate gyrus extending into the dorsal anterior cingulate gyrus in MDD, comorbid MDD and anxiety, and anxiety disorders without comorbid MDD, independent of illness severity, sex, and medication use. Furthermore, we demonstrated reduced right lateral inferior frontal volumes in MDD and reduced left middle/superior temporal volume in anxiety disorders without comorbid MDD. Also, patients with onset of depression before 18 years of age showed lower volumes of the subgenual prefrontal cortex.Conclusions: Our findings indicate that reduced volume of the rostral-dorsal anterior cingulate gyrus is a generic effect in depression and anxiety disorders, independent of illness severity, medication use, and sex. This generic effect supports the notion of a shared etiology and may reflect a common symptom dimension related to altered emotion processing. Specific involvement of the inferior frontal cortex in MDD and lateral temporal cortex in anxiety disorders without comorbid MDD, on the other hand, may reflect disorder-specific symptom clusters. Early onset of depression is associated with a distinct neuroanatomical profile that may represent a vulnerability marker of depressive disorder. Arch Gen Psychiatry. 2010;67(10):1002-1011

Schizophrenia patients might experience difficulties in applying two widely used emotion regulation strategies, reappraisal and suppression. We investigated the relationships among emotion regulation strategies, alexithymia (i.e. inability to identify and verbalize feelings) and the role of pre-morbid IQ on alexithymia in schizophrenia. Participants comprised 31 schizophrenia patients and 44 healthy subjects who were tested on measures of emotion regulation strategies (ERQ), alexithymia (BVAQ) and pre-morbid IQ(NART). Patients reported significantly more use of suppression strategies and tended to use reappraisal strategies less frequently. Patients differed significantly on the cognitive-emotional component of alexithymia. This difference remained significant even with pre-morbid IQ as a covariate. but disapeared with depression as a covariate. Schizophrenia patients have specific difficulties identifying their feelings. These difficulties were related to symptoms of depression. interventions specifically targeted at affect regulation and recognition of emotional state could promote emotional well-being in schizophrenia patients. (C) 2009 Elsevier Ireland Ltd. All rights reserved

Functional magnetic resonance imaging (fMRI) studies have shown that anatomically distinct brain regions are functionally connected during the resting state. Basic topological properties in the brain functional connectivity (BFC) map have highlighted the BFC's small-world topology. Modularity, a more advanced topological property, has been hypothesized to be evolutionary advantageous, contributing to adaptive aspects of anatomical and functional brain connectivity. However, current definitions of modularity for complex networks focus on nonoverlapping clusters, and are seriously limited by disregarding inclusive relationships. Therefore, BFC's modularity has been mainly qualitatively investigated. Here, we introduce a new definition of modularity, based on a recently improved clustering measurement, which overcomes limitations of previous definitions, and apply it to the study of BFC in resting state fMRI of 53 healthy subjects. Results show hierarchical functional modularity in the brain. Hum Brain Mapp 30:2220-2231, 2009. (C) 2008 Wiley-Liss, Inc.

Because of the risk for development of psychopathology such as psychotic symptoms, it has been suggested that studying men with the XXY karyotype may help in the search for underlying cognitive, neural and genetic mechanisms. The aim of this study was to identify cognitive mechanisms that may contribute to disorganization of thought in XXY men.A group of 24 XXY men and two non-clinical control groups (N = 20, N 18) participated in the study. The level of disorganization of thought was measured using the Schizotypal Personality Questionnaire. We assessed IQ lateralization of verbal information processing and executive functions including inhibition and mental flexibility.XXY men with high levels of disorganization showed More severe impairments in mental flexibility and inhibition as compared to non-clinical controls and other XXY men. This subgroup also showed a stronger reduction in lateralization of verbal information processing. IQ measures did not differentiate XXY men with high versus low levels of disorganization.These findings indicate that executive impairments in the domains of inhibition and mental flexibility might play a role in the increased vulnerability for disorganized thought in the XXY group. Reduced lateralization of verbal information processing points to non-optimal cerebral specialization in the XXY group, especially in XXY men with high levels of disorganization. This fits with deficits in brain functions most vulnerable to such Maturational disruptions, i.e. executive dysfunctions. Our findings are in line with those reported for schizophrenia patients with thought disorder. We speculate that the underlying mechanisms of thought disorder probably are deficit specific rather than disorder specific. (C) 2009 Elsevier B.V. All rights reserved.

Although Klinefelter syndrome (47,XXY) has been associated with psychosocial difficulties, knowledge of the social behavioral phenotype is limited. We examined specific social abilities and autism traits in Klinefelter syndrome. Scores of 31 XXY men on the Scale for Interpersonal Behavior and the Autism Spectrum Questionnaire were compared to 24 and 20 control men respectively. XXY men reported increased distress during social interactions and less engagement in specific social behaviors. In the XXY group, levels of autism traits were significantly higher across all dimensions of the autism phenotype. These findings call for a clinical investigation of vulnerability to autism in Klinefelter syndrome. Klinefelter syndrome might serve as a model for studying a role of the X chromosome in social behavioral dysfunction and autism-like behavior.

This paper reviews the published evidence on genetically driven variation in neurotransmitter function and brain circuits involved in emotion. Several studies point to a role of the serotonin transporter promoter polymorphism in amygdala activation during emotion perception. We also discuss other polymorphisms (e.g. the COMT val 158met polymorphism, tryptophan hydroxylase-2 -703 G/T) and putative effects on affective processing in cortical and limbic regions. A different line of research concerns studies with genetic disorders. Although at a less fine-grained level, studies with individuals with aneuploidies of the X chromosome (Turner syndrome and Klinefelter syndrome), who display impairments in emotion processing, have resulted in new insights and hypotheses with regard to X chromosomal influences on brain systems supporting cognition and emotion. These have also implicated a key role for the amygdala. Integration of the emerging evidence, suggests that the study of polymorphisms using brain imaging can potentially elucidate biological pathways and mechanisms contributing to individual differences in brain circuits that may bias behavior and affect risk for psychiatric illness. (C) 2008 Elsevier B.V. All rights reserved.

Impaired social cognition is a frequently observed and disabling characteristic of schizophrenia. An important aspect of social cognition involves making social decisions about others. The present study investigates whether brain activity related to social decision-making differs between patients with schizophrenia and healthy controls. Twelve patients with schizophrenia and 21 control subjects participated in the study. Behavioral performance and brain activity were assessed during a task that involved judging the trustworthiness of faces. We performed region-of-interest-based analyses, which revealed that patients with schizophrenia display specific increases and reductions in activation of the medial orbitofrontal cortex, amygdala and the right insula during social decision-making, areas that play key roles in the network that underlies social decisions. These findings suggest that the impairments in social cognition that are often observed in schizophrenia are, at least in part, related to altered brain activity in these areas. (c) 2007 Elsevier Inc. All rights reserved.

Hallucinations remains one of the most intriguing phenomena in psychopathology. In the past two decades the advent of neuroimaging techniques have allowed researchers to investigate what is happening in the brain of those who experience hallucinations. In this article we review both structural and functional neuroimaging studies of patients with auditory and visual hallucinations as well as a small number of studies that have assessed cognitive processes associated with hallucinations in healthy volunteers. The current literature suggests that in addition to secondary (and occasionally primary) sensory cortices, dysfunction in prefrontal premotor, cingulate, subcortical and cerebellar regions also seem to contribute to hallucinatory experiences. Based on the findings of these studies we tentatively propose a neurocognitive model in which both bottom-up and top-down processes interact to produce these erroneous percepts. Finally, directions for future work are discussed. (c) 2007 Elsevier Ltd. All rights reserved.

BackgroundIt has recently been suggested that auditory hallucinations are the result of a criterion shift when deciding whether or not a meaningful signal has emerged. The approach proposes that a liberal criterion may result in increased false-positive identifications, without additional perceptual deficit. To test this hypothesis, we devised a speech discrimination task and used signal detection theory (SDT) to investigate the underlying cognitive mechanisms.MethodSchizophrenia patients with and without auditory hallucinations and a healthy control group completed a speech discrimination task. They had to decide whether a particular spoken word was identical to a previously presented speech stimulus, embedded in noise. SDT was used on the accuracy data to calculate a measure of perceptual sensitivity (Az) and a measure of response bias (β). Thresholds for the perception of simple tones were determined.ResultsCompared to healthy controls, perceptual thresholds were higher and perceptual sensitivity in the speech task was lower in both patient groups. However, hallucinating patients showed increased sensitivity to speech stimuli compared to non-hallucinating patients. In addition, we found some evidence of a positive response bias in hallucinating patients, indicating a tendency to readily accept that a certain stimulus had been presented.ConclusionsWithin the context of schizophrenia, patients with auditory hallucinations show enhanced sensitivity to speech stimuli, combined with a liberal criterion for deciding that a perceived event is an actual stimulus.