Social brain dysfunctions in schizophrenia: a review of neuroimaging studies

The relationship between nutritional status and white matter integrity in older adults: A diffusion tensor imaging study

OBJECTIVES

The purpose of this study to determinate whether there is a relationship between the nutritional status and white matter integrity in older patients by using Diffusion Tensor Imaging (DTI).

METHODS

The patients were evaluated by Mini-Nutritional Assessment Scale. The patients are categorized in the groups of well-nourished, risk of malnutrition, or malnourished, depending on the overall score> 23.5, 17-23.5, or 17; respectively. All patients had brain MRI and DTI. The mean diffusivity (MD), fractional anisotropy (FA), axial diffusivity (AD) and radial diffusivity (RD) values were calculated by ROI-based method in white matter tracts.

RESULTS

Total of the 224 patients; 86 patients had normal nutrition status (group 1), 107 patients were diagnosed with malnutrition risk (group 2) and 31 patients were diagnosed with malnutrition (group 3). Significantly decreased FA values of genu of corpus callosum, forceps minor and significantly increased MD values of middle cerebellar peduncle, and superior frontooccipital fasciculus were detected in group 2 in comparison to group 1 (p < 0.05). After adjusting for the folate and age, MD and RD values of cingulum remained significantly higher and the AD values of superior cerebellar peduncle remained significantly lower in group 3 (p < 0.05).

CONCLUSIONS

Malnutrition was associated with deteriorated DTI values, especially in cingulum and superior cerebellar peduncle. Assessing the nutritional status of older individuals is crucial to avoid its negative impact on brain.

ADVANCES IN KNOWLEDGE

Early diagnosis of malnutrition-related impaired WM integrity is important for prevention and intervention, and DTI is a useful non-invasive technique to be used for this purpose.

Sex-dependent emergence of prepubertal social dysfunction and augmented dopamine activity in a neurodevelopmental rodent model relevant for schizophrenia

Schizophrenia is a neurodevelopmental psychiatric disorder that often emerges in adolescence, is characterized by social dysfunction, and has an earlier onset in men. These features have been replicated in rats exposed to the mitotoxin methylazoxymethanol acetate (MAM) on gestational day (GD) 17, which as adults exhibit behavioral impairments and dopamine (DA) system changes consistent with a schizophrenia-relevant rodent model. In humans, social withdrawal is a negative symptom that often precedes disease onset and DA system dysfunction and is more pronounced in men. Children and adolescents at high-risk for schizophrenia exhibit social deficits prior to psychotic symptoms (i.e., prodromal phase), which can be used as a predictive marker for future psychopathology. Adult MAM rats also exhibit deficient social interaction, but less is known regarding the emergence of social dysfunction in this model, whether it varies by sex, and whether it is linked to disrupted DA function. To this end, we characterized the ontogeny of social and DA dysfunction in male and female MAM rats during the prepubertal period (postnatal days 33-43) and found sex-specific changes in motivated social behaviors (play, approach) and DA function. Male MAM rats exhibited reduced social approach and increased VTA DA neuron activity compared to saline-treated (SAL) males, whereas female MAM rats exhibited enhanced play behaviors compared to SAL females but no changes in social approach or VTA population activity during this period. These findings demonstrate sex differences in the emergence of social and DA deficits in the MAM model, in which females exhibit delayed emergence.

Neural correlates of mental state decoding and mental state reasoning in schizophrenia

Theory of mind skills are disrupted in schizophrenia. However, various theory of mind tasks measure different neurocognitive domains. This multimodal neuroimaging study aimed to investigate the neuroanatomical correlates of mental state decoding and reasoning components of theory of mind in schizophrenia and healthy controls (HCs) using T1-weighted and diffusion-weighted (DTI) magnetic resonance imaging (MRI). Sixty-two patients with schizophrenia and 34 HCs were included. The Reading the Mind in the Eyes (RMET) and Hinting tests were used to evaluate mental state decoding and reasoning, respectively. Correlations between social cognition and cortical parameters (thickness, volume, surface area), or DTI scalars (fractional anisotropy, axial diffusivity, radial diffusivity) were cluster-based corrected for multiple comparisons. In schizophrenia, RMET scores showed positive correlations in 3 clusters, including left insula thickness, right superior-temporal thickness, left superior-temporal-sulcus volume, and DTI analysis revealed that fractional anisotropy showed positive correlations in 3 clusters, including right inferior-fronto-occipital fasciculus, left forceps-major, left inferior-fronto-occipital fasciculus. In schizophrenia, Hinting test scores showed positive correlations in 3 clusters in T1-weighted MRI, including left superior-temporal-sulcus volume, left superior-temporal-sulcus surface area, left pars-orbitalis volume. In conclusion, this study provided evidence for the involvement of particular cortical regions and white matter tracts in mental state decoding and reasoning.

Multivariate Associations Among White Matter, Neurocognition, and Social Cognition Across Individuals With Schizophrenia Spectrum Disorders and Healthy Controls

BACKGROUND AND HYPOTHESIS

Neurocognitive and social cognitive abilities are important contributors to functional outcomes in schizophrenia spectrum disorders (SSDs). An unanswered question of considerable interest is whether neurocognitive and social cognitive deficits arise from overlapping or distinct white matter impairment(s).

STUDY DESIGN

We sought to fill this gap, by harnessing a large sample of individuals from the multi-center Social Processes Initiative in the Neurobiology of the Schizophrenia(s) (SPINS) dataset, unique in its collection of advanced diffusion imaging and an extensive battery of cognitive assessments. We applied canonical correlation analysis to estimates of white matter microstructure, and cognitive performance, across people with and without an SSD.

STUDY RESULTS

Our results established that white matter circuitry is dimensionally and strongly related to both neurocognition and social cognition, and that microstructure of the uncinate fasciculus and the rostral body of the corpus callosum may assume a "privileged role" subserving both. Further, we found that participant-wise estimates of white matter microstructure, weighted by cognitive performance, were largely consistent with participants' categorical diagnosis, and predictive of (cross-sectional) functional outcomes.

CONCLUSIONS

The demonstrated strength of the relationship between white matter circuitry and neurocognition and social cognition underscores the potential for using relationships among these variables to identify biomarkers of functioning, with potential prognostic and therapeutic implications.

The Neural Correlates of the Social Perception Dysfunction in Schizophrenia: An fMRI Study

Purpose

Patients with schizophrenia show deficits in facial emotion recognition and emotional intensity assessment, and also exhibit structural and functional irregularities in specific brain regions. In this study, we aimed to examine differences in active brain regions involved in processing the Emotion Intensity Recognition Task (EIRT), which can serve as an indicator of emotion recognition and ability to perceive intensity, between patients with schizophrenia and healthy controls (HCs). The purpose of this study was to investigate dysfunctional brain regions and investigate the role of the amygdala in social cognition deficits in patients with schizophrenia by focusing on alterations in amygdala activity linked to facial emotion recognition.

Participants and Methods

Twenty-two patients who met a diagnostic criteria for schizophrenia according to DSM-IV and 27 HCs participated in an MRI scan while completing the EIRT. Behavioral and MRI data were collected and analyzed.

Results

Behavioral results showed that patients with schizophrenia made significantly more errors in recognizing surprise, happiness, sadness, fear, and neutral expressions, and patients with schizophrenia exhibited significantly slower response times in recognizing happy facial expressions. Imaging results showed that schizophrenia patients found hypoactivation in several inferior parietal and temporal regions, in the cerebrum and anterior cingulate; and decreased amygdala activation in individuals with schizophrenia was associated with impaired recognition of fear in facial expressions.

Conclusion

Facial emotion processing deficits are emotion-specific (surprise, happiness, sadness, fear, and neutral expressions) in schizophrenia. Hypoactivation in several inferior parietal and temporal regions, in the cerebrum and anterior cingulate, was thought to contribute to symptom formation in schizophrenia. Reduction in amygdala activation in schizophrenia patients was associated with impairment of the fear-emotional process.

White matter microstructural abnormalities in individuals with attenuated positive symptom syndromes

White matter (WM) microstructural alterations have been extensively studied in patients with psychosis, but research on the microstructure of WM in individuals with attenuated positive symptom syndrome (APSS) is currently limited. To improve the understanding of the neuropathology in APSS, this study investigated the WM of individuals with APSS using diffusion tensor and T1-weighted imaging. Automated fiber quantification was used to calculate the diffusion index values along the trajectories of 20 major fiber tracts in 42 individuals with APSS and 51 age-and sex-matched healthy control (HC) individuals. The diffusion index values in each of fiber tracts were compared node-by-node between the 2 groups. Compared with the HC group, the APSS group showed differences in the diffusion index values in partial segments of the callosum forceps minor, left and right cingulum cingulate, inferior fronto-occipital fasciculus, right corticospinal tract, left superior longitudinal fasciculus, and arcuate fasciculus. Notably, in the APSS group positive associations were found between the axial diffusivity values of the partial nodes of the left and right cingulum cingulate and the current Global Assessment of Functioning scores, as well as between the axial diffusivity values of the partial nodes of the right corticospinal tract and negative symptoms scores and reasoning and problem-solving scores. These findings suggest that individuals with APSS exhibit reduced WM integrity or possible impaired myelin in certain segments of WM tracts involved in the frontal- and limbic-cortical connections. Additionally, abnormal WM tracts appear to be associated with impaired general function and neurocognitive function. This study provides important new insights into the neurobiology of APSS and highlights potential targets for future intervention and treatment.

Pupil dilation reflects the dynamic integration of audiovisual emotional speech

Emotional speech perception is a multisensory process. When speaking with an individual we concurrently integrate the information from their voice and face to decode e.g., their feelings, moods, and emotions. However, the physiological reactions-such as the reflexive dilation of the pupil-associated to these processes remain mostly unknown. That is the aim of the current article, to investigate whether pupillary reactions can index the processes underlying the audiovisual integration of emotional signals. To investigate this question, we used an algorithm able to increase or decrease the smiles seen in a person's face or heard in their voice, while preserving the temporal synchrony between visual and auditory channels. Using this algorithm, we created congruent and incongruent audiovisual smiles, and investigated participants' gaze and pupillary reactions to manipulated stimuli. We found that pupil reactions can reflect emotional information mismatch in audiovisual speech. In our data, when participants were explicitly asked to extract emotional information from stimuli, the first fixation within emotionally mismatching areas (i.e., the mouth) triggered pupil dilation. These results reveal that pupil dilation can reflect the dynamic integration of audiovisual emotional speech and provide insights on how these reactions are triggered during stimulus perception.

CCPNet136: automated detection of schizophrenia using carbon chain pattern and iterative TQWT technique with EEG signals

Objective.Schizophrenia (SZ) is a severe, chronic psychiatric-cognitive disorder. The primary objective of this work is to present a handcrafted model using state-of-the-art technique to detect SZ accurately with EEG signals.Approach.In our proposed work, the features are generated using a histogram-based generator and an iterative decomposition model. The graph-based molecular structure of the carbon chain is employed to generate low-level features. Hence, the developed feature generation model is called the carbon chain pattern (CCP). An iterative tunable q-factor wavelet transform (ITQWT) technique is implemented in the feature extraction phase to generate various sub-bands of the EEG signal. The CCP was applied to the generated sub-bands to obtain several feature vectors. The clinically significant features were selected using iterative neighborhood component analysis (INCA). The selected features were then classified using the k nearest neighbor (kNN) with a 10-fold cross-validation strategy. Finally, the iterative weighted majority method was used to obtain the results in multiple channels.Main results.The presented CCP-ITQWT and INCA-based automated model achieved an accuracy of 95.84% and 99.20% using a single channel and majority voting method, respectively with kNN classifier.Significance.Our results highlight the success of the proposed CCP-ITQWT and INCA-based model in the automated detection of SZ using EEG signals.

Emotion Recognition Deficits in Psychiatric Disorders as a Target of Non-invasive Neuromodulation: A Systematic Review

Background. Social cognition deficits are a core feature of psychiatric disorders, such as schizophrenia and mood disorder, and deteriorate the functionality of patients. However, no definite strategy has been established to treat social cognition (eg, emotion recognition) impairments in these illnesses. Here, we provide a systematic review of the literature regarding transcranial direct current stimulation (tDCS) and repetitive transcranial magnetic stimulation (rTMS) for the treatment of social cognition deficits in individuals with psychiatric disorders. Methods. A literature search was conducted on English articles identified by PubMed, PsycINFO, and Web of Science databases, according to the guidelines of the PRISMA statement. We defined the inclusion criteria as follows: (1) randomized controlled trials (RCTs), (2) targeting patients with psychiatric disorders (included in F20-F39 of the 10th revision of the International Statistical Classification of Diseases and Related Health Problems [ICD-10]), (3) evaluating the effect of tDCS or rTMS, (4) reporting at least one standardized social cognition test. Results. Five papers (3 articles on tDCS and 2 articles on rTMS) met the inclusion criteria which deal with schizophrenia or depression. The significant effects of tDCS or rTMS targeting the left dorsolateral prefrontal cortex on the emotion recognition domain were reported in patients with schizophrenia or depression. In addition, rTMS on the right inferior parietal lobe was shown to ameliorate social perception impairments of schizophrenia. Conclusions. tDCS and rTMS may enhance some domains of social cognition in patients with psychiatric disorders. Further research is warranted to identify optimal parameters to maximize the cognitive benefits of these neuromodulation methods.

A distinct neurocognitive profile: unipolar mania

OBJECTIVE

Despite a growing number of studies reporting patients with a history of mania without depression have several socio-demographic and clinical differences than bipolar disorder patients, unipolar mania is recognized as bipolar I disorder in the most commonly used classification systems. Studies showing that unipolar mania is a separate clinical entity are insufficient in number, and to the best of our knowledge, there has been no study investigating the neuropsychological differences in this area. The aim of this study is to evaluate the neurocognitive differences between unipolar mania, bipolar I disorder and healthy controls, and to reveal the underlying neurocognitive differences.

MATERIALS AND METHODS

Cambridge Neuropsychological Test Automated Battery was applied to 18 unipolar mania, 19 bipolar I disorder patients and 21 healthy controls matched for age, sex and education levels.

RESULTS

Unipolar mania group had worse performance regarding visual memory and executive functions, and had specific social cognition deficits compared to both bipolar I disorder and healthy control groups.

CONCLUSION

The results of our study indicate that unipolar mania might have unique neurocognitive differences compared to bipolar I disorder, which might support the hypothesis that unipolar mania is a distinct neurocognitive disorder within bipolar spectrum disorders.

An atlas of genetic correlations between gestational age and common psychiatric disorders

We aim to systematically explore the potential genetic correlations between five major psychiatric disorders and gestational ages. Genome-wide association study (GWAS) summary datasets of attention deficit/hyperactivity disorder (ADHD), autism spectrum disorder (ASD), bipolar disorder (BD), schizophrenia (SCZ) and major depressive disorder (MDD) in discovery were downloaded from the Psychiatric GWAS Consortium (PGC) website. Suggestive (Raw p < 0.05) genetic associations in the discovery phrase were further replicated in independent GWASs which downloaded from PGC, the FinnGen study or Integrative Psychiatric Research (iPSYCH) website. GWASs of gestational duration, preterm and post-term birth were derived from previous studies of infants from the Early Growth Genetics (EGG) Consortium, the iPSYCH study, and the Genomic and Proteomic Network for Preterm Birth Research (GPN). We calculated genetic correlations using linkage disequilibrium score (LDSC) regression. Mendelian randomization (MR) analyses were performed to investigate the causal effects. We identified four suggestive genetic correlations between psychiatric disorders and gestational age factors in discovery LDSC and two replicated in a confirmation LDSC: gestational duration and ADHD (r_g  = -0.1405, FDR p = 0.0406), post-term birth and SCZ (r_g  = -0.2003, FDR p = 0.0042). We also observed causal effect of post-term birth on SCZ by MR (P_{Weighted median}  = 0.037, P_{Inverse variance weighted}  = 0.007). Our analysis suggested no significant evidence of horizontal pleiotropy and heterogeneity. This study showed the genetic correlation evidences between gestational age phenotypes and psychiatric disorders, providing novel clues for understanding the pathogenic factors of common psychiatric disorders. LAY SUMMARY: Whereas gestational age factors were reported to be associated with psychiatric disorders, the genetic relationship and causality remain to be revealed. The present study reported the first large-scale genetic correlations investigation of the associations between gestational age phenotypes and psychiatric disorders. Results indicate causal relationships between post-term birth and schizophrenia (SCZ), as well as suggestive genetic correlations between gestational duration and attention deficit/hyperactivity disorder (ADHD). This study provided novel clues for understanding the pathogenic factors of common psychiatric disorders.

Cariprazine's Potential in Improving Social Dysfunction in Patients With Schizophrenia: A Perspective

Social dysfunction is one of the most debilitating aspects of schizophrenia. Treatment of this complex phenomenon, constituted by negative, cognitive, and affective symptoms, has been difficult with the available pharmacological agents, hence it represents an unmet medical need. Cariprazine, a novel, third-generation antipsychotic with a unique mechanism of action has been proven to sufficiently alleviate negative, cognitive, and affective symptoms of schizophrenia. These characteristics make this compound a valid candidate for addressing social dysfunction too. In this perspective, we argue that cariprazine can be viewed as a "socializing drug" that has the ability to improve the patient's functionality and ultimately their quality of life. Data from animal research, clinical trials, an observational study, and patient cases are provided.

Somatic engagement alters subsequent neurobehavioral correlates of affective mentalizing

Socio‐emotional encounters involve a resonance of others' affective states, known as affect sharing (AS); and attribution of mental states to others, known as theory‐of‐mind (ToM). Empathy necessitates the integration of both processes, yet their interaction during emotional episodes and subsequent generation of inferences on others' affective states has rarely been tested. To address this, we developed a novel experimental design, wherein we manipulated AS by presenting nonverbal emotionally negative movies twice—each time accompanied by one of two soundtracks that accentuated either somatic cues or externally generated sounds. Movies were followed by questions addressing affective‐ToM (emotional inferences), cognitive‐ToM (inferences on beliefs and knowledge), and non‐ToM aspects. Results revealed a neural differentiation between AS, affective‐ToM, and cognitive‐ToM. AS movies activated regions that have been implicated in emotional (e.g., amygdala) and somatosensory processing, and synchronized brain activity between participants in the latter. Affective‐ToM activated the middle insula, limbic regions, and both ventral and dorsal portions of the medial prefrontal cortex (ventral medial prefrontal cortex [VMPFC] and dorsal medial prefrontal cortex [DMPFC], respectively), whereas cognitive‐ToM activated posteromedial and lateral–prefrontal and temporal cortices. Critically, AS movies specifically altered neural activation in AS and ToM‐related regions during subsequent affective‐ToM inferences, most notably in the DMPFC. Moreover, DMPFC–VMPFC connectivity correlated with affective‐ToM accuracy, when such questions followed AS movies. Our results associate empathic processes with designated neural activations and shed light on how neuro‐behavioral indices of affective ToM are shaped by preceding somatic engagement.

Stress and the Role of the Gut-Brain Axis in the Pathogenesis of Schizophrenia: A Literature Review

Schizophrenia is a severe neuropsychiatric disorder, and its etiology remains largely unknown. Environmental factors have been reported to play roles in the pathogenesis of schizophrenia, and one of the major environmental factors identified for this disorder is psychosocial stress. Several studies have suggested that stressful life events, as well as the chronic social stress associated with city life, may lead to the development of schizophrenia. The other factor is the gut–brain axis. The composition of the gut microbiome and alterations thereof may affect the brain and may lead to schizophrenia. The main interest of this review article is in overviewing the major recent findings on the effects of stress and the gut–brain axis, as well as their possible bidirectional effects, in the pathogenesis of schizophrenia.

Efficient Brain Connectivity Reconfiguration Predicts Higher Marital Quality and Lower Depression

Social-information processing is important for successful romantic relationships and protecting against depression, and depends on functional connectivity (FC) within and between large-scale networks. Functional architecture evident at rest is adaptively reconfigured during task and there were two possible associations between brain reconfiguration and behavioral performance during neurocognitive tasks (efficiency effect and distraction-based effect). This study examined relationships between brain reconfiguration during social-information processing and relationship-specific and more general social outcomes in marriage. Resting-state FC was compared with FC during social-information processing (watching relationship-specific and general emotional stimuli) of 29 heterosexual couples, and the FC similarity (reconfiguration efficiency) was examined in relation to marital quality and depression 13 months later. The results indicated wives' reconfiguration efficiency (globally and in visual association network) during relationship-specific stimuli processing was related to their own marital quality. Higher reconfiguration efficiency (globally and in medial frontal, frontal-parietal, default mode, motor/sensory and salience networks) in wives during general emotional stimuli processing was related to their lower depression. These findings suggest efficiency effects on social outcomes during social cognition, especially among married women. The efficiency effects on relationship-specific and more general outcome are respectively higher during relationship-specific stimuli or general emotional stimuli processing.

Pharmacological Treatment for Social Cognition: Current Evidence

Cognitive impairment is currently considered a core feature of schizophrenia (SZ) and is gaining attention as a fundamental therapeutic target. Standard treatment for SZ involves the use of antipsychotics that are successfully used to control positive symptoms and disorganized behaviour. However, it is still unclear whether they are effective on social cognition (SC) impairment. Furthermore, different medications are currently being studied to improve SC in patients with SZ. A literature search on this topic was conducted using the PubMed database. All kinds of publications (i.e., reviews, original contributions and case reports) written in English and published in the last 15 years were included. The aim of our literature review is to draw a picture of the current state of the pharmacological treatment of SC impairment in SZ.

Neural Correlates of Mentalizing in Individuals With Clinical High Risk for Schizophrenia: ALE Meta-Analysis

Psychotic disorder refers to a spectrum of disorders that have multiple etiologies, due to the complex interaction of biological and genetic vulnerability with familial and cultural factors. A clinical high risk (CHR) for schizophrenia is defined as the presence of brief, attenuated, or intermittent psychotic symptoms in non-schizophrenic individuals. The transition to schizophrenia appears significantly more frequent in this at-risk population than in the general population. Moreover, the ability to attribute mental states to others, known as mentalizing or theory of mind, and its neural correlates found in individuals with CHR are similar to those described in patients with schizophrenia. We have therefore explored neurofunctional correlates of mentalizing in individuals with CHR vs. healthy controls, in order to identify the differences in brain activation. A neural coordinate-based activation likelihood estimation meta-analysis of existing neuroimaging data revealed that three regions displayed decreased activation in individuals with CHR, compared with healthy controls: the right temporoparietal junction, the right middle temporal gyrus, and the left precuneus. These results, combined with those in the literature, further support the hypothesis that abnormal activation of posterior brain regions involved in mentalizing correlates with psychotic symptoms in help-seeking individuals.

Efficacy and Safety of Multi-Session Transcranial Direct Current Stimulation on Social Cognition in Schizophrenia: A Study Protocol for an Open-Label, Single-Arm Trial

Backgrounds: Social cognition is defined as the mental operations underlying social behavior. Patients with schizophrenia elicit impairments of social cognition, which is linked to poor real-world functional outcomes. In a previous study, transcranial direct current stimulation (tDCS) improved emotional recognition, a domain of social cognition, in patients with schizophrenia. However, since social cognition was only minimally improved by tDCS when administered on frontal brain areas, investigations on the effect of tDCS on other cortical sites more directly related to social cognition are needed. Therefore, we present a study protocol to determine whether multi-session tDCS on superior temporal sulcus (STS) would improve social cognition deficits of schizophrenia. Methods: This is an open-label, single-arm trial, whose objective is to investigate the efficacy and safety of multi-session tDCS over the left STS to improve social cognition in patients with schizophrenia. The primary outcome measure will be the Social Cognition Screening Questionnaire. Neurocognition, functional capacity, and psychotic symptoms will also be evaluated by the Brief Assessment of Cognition in Schizophrenia, UCSD Performance-Based Skills Assessment-Brief, and Positive and Negative Syndrome Scale, respectively. Data will be collected at baseline, and 4 weeks after the end of intervention. If social cognition is improved in patients with schizophrenia by tDCS based on this protocol, we may plan randomized controlled trial.

Association of visual motor processing and social cognition in schizophrenia

Patients with schizophrenia have difficulties in social cognitive domains including emotion recognition and mentalization, and in sensorimotor processing and learning. The relationship between social cognitive deficits and sensorimotor function in patients with schizophrenia remains largely unexplored. With the hypothesis that impaired visual motor processing may decelerate information processing and subsequently affects various domains of social cognition, we examined the association of nonverbal emotion recognition, mentalization, and visual motor processing in schizophrenia. The study examined mentalization using the verbal subset of the Chinese version of Theory of Mind (CToM) Task, an equivalent task of the Faux Pas Test; emotion recognition using the Diagnostic Analysis of Nonverbal Accuracy 2-Taiwan version (DANVA-2-TW), and visual motor processing using a joystick tracking task controlled for basic motor function in 34 individuals with chronic schizophrenia in the community and 42 healthy controls. Patients with schizophrenia had significantly worse performance than healthy controls in social cognition, including facial, prosodic emotion recognition, and mentalization. Visual motor processing was also significantly worse in patients with schizophrenia. Only in patients with schizophrenia, both emotion recognition (mainly in prosodic modality, happy, and sad emotions) and mentalization were positively associated with their learning capacity of visual motor processing. These findings suggest a prospective role of sensorimotor function in their social cognitive deficits. Despite that the underlying neural mechanism needs further research, our findings may provide a new direction for restoration of social cognitive function in schizophrenia by enhancing visual motor processing ability.

Role of BDNF in the development of an OFC-amygdala circuit regulating sociability in mouse and human

Social deficits are common in many psychiatric disorders. However, due to inadequate tools for manipulating circuit activity in humans and unspecific paradigms for modeling social behaviors in rodents, our understanding of the molecular and circuit mechanisms mediating social behaviors remains relatively limited. Using human functional neuroimaging and rodent fiber photometry, we identified a mOFC-BLA projection that modulates social approach behavior and influences susceptibility to social anxiety. In humans and knock-in mice with a loss of function BDNF SNP (Val66Met), the functionality of this circuit was altered, resulting in social behavioral changes in human and mice. We further showed that the development of this circuit is disrupted in BDNF Met carriers due to insufficient BDNF bioavailability, specifically during a peri-adolescent timeframe. These findings define one mechanism by which social anxiety may stem from altered maturation of orbitofronto-amygdala projections and identify a developmental window in which BDNF-based interventions may have therapeutic potential.

Paliperidone Compared with Haloperidol on the Theory of Mind Tasks in Schizophrenia: A Pilot Trial

PURPOSE

Theory of mind (ToM) is an important part of social cognitive function and is associated with medial prefrontal cortical (mPFC) activity. This study aimed to evaluate the efficacy of paliperidone in improving ToM task performance in patients with schizophrenia compared with haloperidol.

PATIENTS AND METHODS

This study was a single-center, single-blinded (assessor), parallel-group randomized clinical trial of patients with schizophrenia randomized to paliperidone or haloperidol. ToM was assessed at weeks 0, 8, 12, and 16 using the first-order belief, higher-order belief, faux-pas, and Reading the Mind in the Eyes tests. The primary outcome was the change in the ToM performance scores from baseline to after 16 weeks of treatment.

RESULTS

The participants received paliperidone (n = 29) or haloperidol (n = 31). For the first-order belief task, there were no between-group differences (P > 0.05) but time differences in both groups (P < 0.05). For the higher-order belief task, there were no between-group differences (P > 0.05), but there were time differences in both groups (P < 0.05) and a time×group interaction in the paliperidone group only (P < 0.05). For the faux-pas task, there was a difference between groups at week 16 (P < 0.05), and the improvement in time was significant for the paliperidone group only (P < 0.05). For the Reading the Mind in the Eyes task, there was an improvement over time for the paliperidone group only (P < 0.05). Safety was manageable in both groups.

CONCLUSION

Paliperidone treatment might be more effective than haloperidol in improving ToM task performance in schizophrenia.

TRIAL REGISTRATION

chictr.org.cn_identifier ChiCTR-IPR-15007635.

Meta-Analysis of Sensorimotor Gating Deficits in Patients With Schizophrenia Evaluated by Prepulse Inhibition Test

Prepulse inhibition (PPI) of startle is an operational measure of sensorimotor gating that is often impaired in patients with schizophrenia. Despite the large number of studies, there is considerable variation in PPI outcomes reported. We conducted a systematic review and meta-analysis investigating PPI impairment in patients with schizophrenia compared with healthy control subjects, and examined possible explanations for the variation in results between studies. Major databases were screened for observational studies comparing healthy subjects and patients with schizophrenia for the prepulse and pulse intervals of 60 and 120 ms as primary outcomes, ie, PPI-60 and PPI-120. Standardized mean difference (SMD) and 95% confidence intervals (CI) were extracted and pooled using random effects models. We then estimated the mean effect size of these measures with random effects meta-analyses and evaluated potential PPI heterogeneity moderators, using sensitivity analysis and meta-regressions. Sixty-seven primary studies were identified, with 3685 healthy and 4290 patients with schizophrenia. The schizophrenia group showed reduction in sensorimotor gating for both PPI-60 (SMD = -0.50, 95% CI = [-0.61, -0.39]) and PPI-120 (SMD = -0.44, 95% CI = [-0.54, -0.33]). The sensitivity and meta-regression analysis showed that sample size, gender proportion, imbalance for gender, source of control group, and study continent were sources of heterogeneity (P < .05) for both PPI-60 and PPI-120 outcomes. Our findings confirm a global sensorimotor gating deficit in schizophrenia patients, with overall moderate effect size for PPI-60 and PPI-120. Methodological consistency should decrease the high level of heterogeneity of PPI results between studies.

Relationship between Basic Neurological Cognition and Social Cognition among Allen Cognitive Disability Levels of Acquired Brain Injury

(1) Background: There are various cognitive, perceptual, and social problems associated with acquired brain injury (ABI). The Allen cognitive impairment level indicates the degree of cognitive function required for everyday activities. Until recently, there have been no studies on the relationship between basic neurological cognition and social cognitive function according to the Allen cognitive level (ACL). The aim of this study is to identify the relationship between basic neurological and social cognition among Allen cognitive disability levels of ABI. (2) Methods: Thirty-four patients with ABI were identified. Cartoon Intention Inference Task (CIIT), Social Behavior Sequence Task (SBST), Korean version Mimi-Mental Status Examination (K-MMSE), and Lowenstein Occupational Therapy Cognitive Assessment (LOTCA)-tests were administered to examine the differences in neurological and social cognitive functions according to each participant's Allen Cognitive Level Screening (ACLS). (3) Results: There were significant differences between K-MMSE, LOTCA, CIIT and SBST results among Allen cognitive levels (p < 0.05). There was a linear correlation between K-MMSE (r = 0.778, p < 0.01), LOTCA-total score (r = 0.627, p < 0.01), LOTCA-orientation (r = 0.470, p = 0.01), LOTCA-thinking operation (r = 0.341, p < 0.05), CIIT (r = 0.817, p < 0.05), and SBST (r = 0.376, p < 0.05) and ACL. Stepwise multivariate regression showed that the subscales affecting the ACLS score were SBST (β = 0.239, p = 0.000) and K-MMSE (β = 0.068, p = 0.001). The explanatory power of this regression equation, R², was 0.767. (4) Conclusions: A significant difference was found in neurological and social cognitive function according to the ACL level of the ABI patient. In addition, there was a linear correlation between the ACLS scores of the ABI patients and the underlying neurological cognitive function and social cognition. The higher the overall functional cognitive level (i.e., the group with higher ACLS scores), and the lower the degree of help required in daily life, the higher both the neurological cognition level and social cognitive level were determined to be.

Uncinate fasciculus white matter connectivity related to impaired social perception and cross-sectional and longitudinal symptoms in patients with schizophrenia spectrum psychosis

Dysfunctional social-emotional perception in patients with schizophrenia can result in adverse clinical symptoms and poorer long-term outcomes. The white matter tracts that interact among a number of brain regions have an important role to play. However, few neuroimaging studies focus on the effects of white matter connectivity on social-emotional perception in schizophrenia and its impact on patients' clinical symptoms and long-term outcomes. Forty-one patients with schizophrenia spectrum psychosis and 42 healthy controls underwent structural magnetic resonance imaging. The white matter fractional anisotropy values of the emotion recognition areas, the bilateral anterior thalamic radiation, inferior longitudinal fasciculus, cingulum bundle, superior longitudinal fasciculus, and uncinate fasciculus were compared between patients with schizophrenia spectrum psychosis and healthy controls. Social-emotional perception levels and symptom severity at baseline and after 1 year were examined. A group analysis showed that white matter connectivity was significantly lower in the bilateral anterior thalamic radiation, cingulum bundle, right inferior longitudinal fasciculus, and uncinate fasciculus of patients with schizophrenia spectrum psychosis compared to the healthy controls. Contrastingly, a correlation analysis revealed that larger right uncinate fasciculus fractional anisotropy values were associated with lower social-emotional perception levels in patients with schizophrenia spectrum psychosis. Additionally, the white matter fractional anisotropy values of the right uncinate fasciculus showed a significant positive correlation with the severity of positive symptoms at baseline and with poor outcomes after 1 year. The findings of the present study suggest that impaired social-emotional perception in patients with schizophrenia spectrum psychosis is associated with larger white matter connectivity of the uncinate fasciculus, which is also associated with more severe symptoms at baseline and after 1-year. These results suggest that the uncinate fasciculus could affect the pathophysiology of schizophrenia.

Polygenic risk for autism spectrum disorder affects left amygdala activity and negative emotion in schizophrenia

Although the diagnoses based on phenomenology have many practical advantages, accumulating evidence shows that schizophrenia and autism spectrum disorder (ASD) share some overlap in genetics and clinical presentation. It remains largely unknown how ASD-associated polygenetic risk contributes to the pathogenesis of schizophrenia. In the present study, we calculated high-resolution ASD polygenic risk scores (ASD PRSs) and selected optimal ten ASD PRS with minimal P values in the association analysis of PRSs, with schizophrenia to assess the effect of ASD PRS on brain neural activity in schizophrenia cases and controls. We found that amplitude of low-frequency fluctuation in left amygdala was positively associated with ASD PRSs in our cohort. Correlation analysis of ASD PRSs with facial emotion recognition test identified the negative correlation of ASD PRSs with negative emotions in schizophrenia cases and controls. Finally, functional enrichment analysis of PRS genes revealed that neural system function and development, as well as signal transduction, were mainly enriched in PRS genes. Our results provide empirical evidence that polygenic risk for ASD contributes to schizophrenia by the intermediate phenotypes of left amygdala function and emotion recognition. It provides a promising strategy to understand the relationship between phenotypes and genotypes shared in mental disorders.

Relationships between abnormal neural activities and cognitive impairments in patients with drug-naive first-episode schizophrenia

BACKGROUND

Prior resting state functional Magnetic Resonance Imaging studies (rs-fMRI) via the regional homogeneity (ReHo) method have demonstrated inconsistent and conflicting results because of several confounding factors, such as small sample size, medicinal influence, and illness duration. Relationships between ReHo measures and cognitive impairments in patients with drug-naive First-Episode Schizophrenia (dn-FES) are rarely reported. This study was conducted to explore the correlations between ReHo measures and cognitive deficits and clinical symptoms in patients with dn-FES.

METHODS

A total of 69 patients with dn-FES and 74 healthy controls were recruited. MATRICS Consensus Cognitive Battery (MCCB), Wechsler Adult Intelligence Scale (WAIS), and Positive And Negative Syndrome Scale (PANSS) were used to assess cognitive function, Intelligence Quotient (IQ), and clinical symptoms, respectively. The correlations between ReHo maps and cognitive deficits and the severity of symptoms were examined using strict correlation analysis.

RESULTS

ReHo values in right Middle Frontal Gyrus (MFG) and Superior Frontal Gyrus (SFG) increased in dn-FES group, whereas ReHo values in right cuneus decreased. Correlation analysis showed that the ReHo values in right MFG positively correlated with attention/vigilance impairments, social cognition deficits, and the severity of clinical manifestations.

CONCLUSIONS

These findings suggested that abnormal spontaneous activities in right MFG reflect illness severity and cognitive deficits, which also serve as a basis for establishing objective diagnostic markers and might be a clinical intervention target for treating patients with schizophrenia.

Cingulum bundle abnormalities and risk for schizophrenia

BACKGROUND

The cingulum bundle (CB) is a major white matter fiber tract of the limbic system that underlies cingulate cortex, passing longitudinally over the corpus callosum. The connectivity of this white matter fiber tract plays a major role in emotional expression, attention, motivation, and working memory, all of which are affected in schizophrenia. Myelin related CB abnormalities have also been implicated in schizophrenia. The purpose of this study is to determine whether or not CB abnormalities are evident in individuals at clinical high risk (CHR) for psychosis, and whether or not cognitive deficits in the domains subserved by CB are related to its structural abnormalities.

METHODS

Diffusion Tensor Imaging (DTI) was performed on a 3 T magnet. DT tractography was used to evaluate CB in 20 individuals meeting CHR criteria (13 males/7 females) and 23 healthy controls (12 males/11 females) group matched on age, gender, parental socioeconomic status, education, and handedness. Fractional anisotropy (FA), a measure of white matter coherence and integrity, radial diffusivity (RD), thought to reflect myelin integrity, trace, a possible marker of atrophy, and axial diffusivity (AD), thought to reflect axonal integrity, were averaged over the entire tract and used to investigate CB abnormalities in individuals at CHR for psychosis compared with healthy controls.

RESULTS

Significant group differences were found between individuals at CHR for psychosis and controls for FA (p = 0.028), RD (p = 0.03) and trace (p = 0.031), but not for AD (p = 0.09). We did not find any significant correlations between DTI measures and clinical symptoms.

CONCLUSION

These findings suggest abnormalities (possibly myelin related) in the CB in individuals at CHR for psychosis.

Neural correlates of theory of mind and empathy in schizophrenia: An activation likelihood estimation meta-analysis

Social cognition impairment predicts social functioning in schizophrenia. Several studies have found abnormal brain activation in patients with schizophrenia during social cognition tasks. Nevertheless, no coordinate-based meta-analysis comparing the neural correlates of theory of mind and empathy had been done in this population. Our aim was to explore neural correlates related to theory of mind and empathy in patients with schizophrenia compared to healthy controls, in order to identify abnormal brain activation related to emotional content during mental state attribution in schizophrenia. We performed a neural-coordinate-based Activation Likelihood Estimation (ALE) meta-analysis of existing neuroimaging data in the literature to distinguish between abnormal brain maps associated with emotional attribution and those associated with intention/belief inference. We found that brain activation in patients group was significantly decreased in the right ventrolateral prefrontal cortex (VLPFC) during emotional attribution, while there was a significant decrease in the left posterior temporo-parietal junction (TPJ) during intention/belief attribution. Using a meta-analytic connectivity modeling approach (MACM), we demonstrated that both regions are coactivated with other brain regions known to play a role in social cognition, including the bilateral anterior insula, right TPJ, left amygdala and dorsolateral prefrontal cortex. In addition, abnormal activation in both the left TPJ and right VLPFC was previously reported in association with verbal-auditory hallucinations and a "jumping to conclusions" cognitive bias. Thus, these regions could be valuable targets for therapeutic interventions in schizophrenia.

Neuromagnetic activation and oscillatory dynamics of stimulus-locked processing during naturalistic viewing

Naturalistic stimuli such as watching a movie while in the scanner provide an ecologically valid paradigm that has the potential of extracting valuable information on how the brain processes complex stimuli in realistic visual and auditory contexts. Naturalistic viewing is also easier to conduct with challenging participant groups including patients and children. Given the high temporal resolution of MEG, in the present study, we demonstrate how a short movie clip can be used to map distinguishable activation and connectivity dynamics underlying the processing of specific classes of visual stimuli such as face and hand manipulations, as well as contrasting activation dynamics for auditory words and non-words. MEG data were collected from 22 healthy volunteers (6 females, 3 left handed, mean age - 27.7 ​± ​5.28 years) during the presentation of naturalistic audiovisual stimuli. The MEG data were split into trials with the onset of the stimuli belonging to classes of interest (words, non-words, faces, hand manipulations). Based on the components of the averaged sensor ERFs time-locked to the visual and auditory stimulus onset, four and three time-windows, respectively, were defined to explore brain activation dynamics. Pseudo-Z, defined as the ratio of the source-projected time-locked power to the projected noise power for each vertex, was computed and used as a proxy of time-locked brain activation. Statistical testing using the mean-centered Partial Least Squares analysis indicated periods where a given visual or auditory stimuli had higher activation. Based on peak pseudo-Z differences between the visual conditions, time-frequency resolved analyses were performed to assess beta band desynchronization in motor-related areas, and inter-trial phase synchronization between face processing areas. Our results provide the first evidence that activation and connectivity dynamics in canonical brain regions associated with the processing of particular classes of visual and auditory stimuli can be reliably mapped using MEG during presentation of naturalistic stimuli. Given the strength of MEG for brain mapping in temporal and frequency domains, the use of naturalistic stimuli may open new techniques in analyzing brain dynamics during ecologically valid sensation and perception.

Gamma electroencephalographic coherence and theory of mind in healthy subjects

PURPOSE

Structural brain imaging has revealed that damage to different brain regions may impair theory of mind (ToM) while functional imaging has shown that distributed neural circuits are activated by ToM and empathy. However, the coherence of the electroencephalogram (EEG) frequencies in a definite time span may change during these processes, indicating different neurophysiological correlates. This study evaluated the changes of EEG coherence during ToM tasks in comparison with Empathy, Physical causality, and baseline conditions, aiming to determine the neurophysiological correlates of ToM.

METHODS

Sixteen healthy adults underwent a visual activation paradigm using 30 comic strips concerning ToM, Empathy, or Physical causality during EEG recording. The interhemispheric coherence was estimated using a bivariate autoregressive (AR) parametric model. The coherence spectra were analyzed in the alpha, beta, and gamma frequency EEG bands.

RESULTS

Coherence analysis taking all of the responses showed that in the gamma band, in comparison with the Empathy, Physical causality, and baseline conditions, ToM was associated with significantly higher peaks between the frontal and parietal areas in the right hemisphere and, in comparison with the Physical causality and baseline conditions, in the left hemisphere. Analysis taking the correct responses confirmed these results.

CONCLUSIONS

In healthy adults, ToM processes are associated with immediate specific changes of brain connectivity, as expressed by high cortical coherence within the right frontal and parietal areas. These previously unexplored aspects indicate an online involvement of the right hemisphere networks in normal ToM. In patients with epilepsy, the study of EEG coherence during specific tasks may help determine the neural dysfunctions associated with impaired ToM. This article is part of the Special Issue "Epilepsy and social cognition across the lifespan".

Decreased Cross-Domain Mutual Information in Schizophrenia From Dynamic Connectivity States

The study of dynamic functional network connectivity (dFNC) has been important to understand the healthy and diseased brain. Recent developments model groups of functionally related brain structures (defined as functional domains) as entities that can send and receive information. A domain analysis starts by detecting a finite set of connectivity patterns known as domain states within each functional domain. Dynamic functional domain connectivity (DFDC) is a novel information theoretic framework for studying the temporal sequence of the domain states and the amount of information shared among domains. In this setting, the information flow among functional domains can be compared to the flow of bits among entities in a digital network. Schizophrenia is a chronic psychiatric disorder which is associated with how the brain processes information. Here, we employed the DFDC framework to analyze a dataset containing resting-state fMRI scans from 163 healthy controls (HCs) and 151 schizophrenia patients (SZs). As in other information theory methods, this study measured domain state probabilities, entropy within each DFDC and the cross-domain mutual information (CDMI) between pairs of DFDC. Results indicate that SZs show significantly higher (transformed) entropy than HCs in subcortical (SC)-SC; default mode network (DMN)-visual (VIS) and frontoparietal (FRN)-VIS DFDCs. SZs also show lower (transformed) CDMI between SC-VIS vs. SC-sensorimotor (SM), attention (ATTN)-VIS vs. ATTN-SM and ATTN-SM vs. ATTN-ATTN DFDC pairs after correcting for multiple comparisons. These results imply that different DFDC pairs function in a more independent manner in SZs compared to HCs. Our findings present evidence of higher uncertainty and randomness in SZ brain function.

Hyper- and Hypomentalizing in Patients with First-Episode Schizophrenia: fMRI and Behavioral Studies

BACKGROUND

Historically, research investigating neural correlates of mentalizing deficits in schizophrenia has focused on patients who have been ill for several years with lengthy exposure to medication. Little is known about the neural and behavioral presentations of theory-of-mind deficits in schizophrenia, shortly after the first episode of psychosis.

METHODS

We investigated social cognition in 17 recently diagnosed first-episode schizophrenia (FES) patients with little or no exposure to antipsychotic medication and 1:1 matched healthy controls. We recorded behavioral and neural responses to the Animated Triangles Task (ATT), which is a nonverbal validated mentalizing task that measures the ascription of intentionality to the movements of objects.

RESULTS

FES patients under-interpreted social cues and over-interpreted nonsocial cues. These effects were influenced by current intelligence (IQ). Control group and FES neural responses replicated earlier findings in healthy adults. However, a region of anterior medial prefrontal cortex (amPFC) of FES patients showed a different response pattern to that of controls. Unlike healthy controls, patients increased activity in this social cognition region while studying "random" movements of shapes, as compared to the study of movements normally interpreted as "intentional".

CONCLUSIONS

Mentalizing deficits in FES consists of hypo- and hypermentalizing. The neural pattern of FES patients is consistent with deficits in the ability to switch off mentalizing processes in potentially social contexts, instead increasing them when intentionality is not forthcoming. Overall, results demonstrate complexities of theory of mind deficits in schizophrenia that should be considered when offering social cognitive training programs.

Genetic factors associated with empathy in humans and mice

The neurocognitive ability to recognize and share the mental states of others is crucial for our emotional experience and social interaction. Extensive human studies have informed our understanding of the psychobehavioral and neurochemical bases of empathy. Recent evidence shows that simple forms of empathy are conserved from rodents to humans, and rodent models have become particularly useful for understanding the neurobiological correlates of empathy. In this review, we first summarize aspects of empathy at the behavioral and neural circuit levels, and describe recent developments in rodent model behavioral paradigms. We then highlight different neurobiological pathways involved in empathic abilities, with special emphasis on genetic polymorphisms associated with individual differences in empathy. By directly assessing various neurochemical correlates at molecular and neural circuit levels using relevant animal models, we conclude with the suggestion that rodent research can significantly advance our understanding of the neural basis of empathy. This article is part of the Special Issue entitled 'The neuropharmacology of social behavior: from bench to bedside'.

Social Cognition Deficits as a Target of Early Intervention for Psychoses: A Systematic Review

Backgrounds: Social cognition deficits are a core feature of schizophrenia and deteriorate functionality of patients. However, evidence is sparse for the treatment effect on social cognition impairments in the early stage of psychosis. Here, we provide a systematic review of the literature on social cognitive impairment in early psychosis in relation to its intervention. Methods: A literature search was conducted on English articles identified by Web of Science and PubMed databases, according to the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement. Results: Five papers met the inclusion criteria. Results from two studies of cognitive training and one study of modafinil indicate positive results regarding social cognition outcomes in patients with early psychosis. On the other hand, two studies with oxytocin and modafinil did not suggest such effects. Conclusions: Further research is warranted to explore the benefit of early intervention into disturbances of social cognition in psychoses.

Neurobiology and treatment of social cognition in schizophrenia: Bridging the bed-bench gap

Social cognition refers to the psychological processes involved in the perception, encoding, storage, retrieval, and regulation of information about others and ourselves. This process is essential for survival and reproduction in complex social environments. Recent evidence suggests that impairments in social cognition frequently occur in schizophrenia, mainly contributing to poor functional outcomes, including the inability to engage in meaningful work and maintain satisfying interpersonal relationships. With the ambiguous definition of social cognition, the neurobiology underlying impaired social cognition remains unknown, and the effectiveness of currently available intervention strategies in schizophrenia remain limited. Considering the advances and challenges of translational research for schizophrenia, social cognition has been considered a high-priority domain for treatment development. Here, we describe the current state of the framework, clinical concerns, and intervention approaches for social cognition in schizophrenia. Next, we introduce translatable rodent models associated with schizophrenia that allow the evaluation of different components of social behaviors, providing deeper insights into the neural substrates of social cognition in schizophrenia. Our review presents a valuable perspective that indicates the necessity of building bridges between basic and clinical science researchers for the development of novel therapeutic approaches in impaired social cognition in schizophrenia.

Negative Schizotypy and Altered Functional Connectivity During Facial Emotion Processing

BACKGROUND

Impairment in facial emotion perception is an important domain of social cognition deficits in schizophrenia. Although impaired facial emotion perception has been found in individuals with negative schizotypy (NS), little is known about the corresponding change in brain functional connectivity.

METHODS

Sixty-four participants were classified into a high NS group (n = 34) and a low NS group (n = 30) based on their total scores on the Chapman scales for physical and social anhedonia. All participants undertook a facial emotion discrimination functional imaging task that consisted of four emotional valences (angry, fear, happy, and neutral). For univariate analysis, the signal change at the bilateral amygdala was compared for each emotional contrast using SPSS (P < .05). For the functional connectivity analysis, we calculated the beta-series functional connectivity of the bilateral amygdala with the medial prefrontal cortex (mPFC) and compared the group differences in SPM12 (P < .05, small volume family-wise error correction).

RESULTS

No significant differences were found between the high and low NS groups in accuracy and reaction time in the facial emotion discrimination task. The high NS group showed reduced brain activations at the amygdala under fearful and neutral conditions. Reduced functional connectivity between the amygdala and the mPFC/dorsal anterior cingulate cortex under the happy and fearful conditions in the high NS group was also found.

CONCLUSIONS

Our findings suggest that the individuals with high NS showed altered brain activity and functional connectivity at the amygdala during facial emotion processing and provide new evidence for understanding social cognition deficits in at-risk individuals.

Classification of multi-site MR images in the presence of heterogeneity using multi-task learning

With the advent of Big Data Imaging Analytics applied to neuroimaging, datasets from multiple sites need to be pooled into larger samples. However, heterogeneity across different scanners, protocols and populations, renders the task of finding underlying disease signatures challenging. The current work investigates the value of multi-task learning in finding disease signatures that generalize across studies and populations. Herein, we present a multi-task learning type of formulation, in which different tasks are from different studies and populations being pooled together. We test this approach in an MRI study of the neuroanatomy of schizophrenia (SCZ) by pooling data from 3 different sites and populations: Philadelphia, Sao Paulo and Tianjin (50 controls and 50 patients from each site), which posed integration challenges due to variability in disease chronicity, treatment exposure, and data collection. Some existing methods are also tested for comparison purposes. Experiments show that classification accuracy of multi-site data outperformed that of single-site data and pooled data using multi-task feature learning, and also outperformed other comparison methods. Several anatomical regions were identified to be common discriminant features across sites. These included prefrontal, superior temporal, insular, anterior cingulate cortex, temporo-limbic and striatal regions consistently implicated in the pathophysiology of schizophrenia, as well as the cerebellum, precuneus, and fusiform, middle temporal, inferior parietal, postcentral, angular, lingual and middle occipital gyri. These results indicate that the proposed multi-task learning method is robust in finding consistent and reliable structural brain abnormalities associated with SCZ across different sites, in the presence of multiple sources of heterogeneity.

The "social brain" is highly sensitive to the mere presence of social information: An automated meta-analysis and an independent study

How the human brain processes social information is an increasingly researched topic in psychology and neuroscience, advancing our understanding of basic human cognition and psychopathologies. Neuroimaging studies typically seek to isolate one specific aspect of social cognition when trying to map its neural substrates. It is unclear if brain activation elicited by different social cognitive processes and task instructions are also spontaneously elicited by general social information. In this study, we investigated whether these brain regions are evoked by the mere presence of social information using an automated meta-analysis and confirmatory data from an independent study of simple appraisal of social vs. non-social images. Results of 1,000 published fMRI studies containing the keyword of “social” were subject to an automated meta-analysis (http://neurosynth.org). To confirm that significant brain regions in the meta-analysis were driven by a social effect, these brain regions were used as regions of interest (ROIs) to extract and compare BOLD fMRI signals of social vs. non-social conditions in the independent study. The NeuroSynth results indicated that the dorsal and ventral medial prefrontal cortex, posterior cingulate cortex, bilateral amygdala, bilateral occipito-temporal junction, right fusiform gyrus, bilateral temporal pole, and right inferior frontal gyrus are commonly engaged in studies with a prominent social element. The social–non-social contrast in the independent study showed a strong resemblance to the NeuroSynth map. ROI analyses revealed that a social effect was credible in 9 out of the 11 NeuroSynth regions in the independent dataset. The findings support the conclusion that the “social brain” is highly sensitive to the mere presence of social information.

Social cognition and self-other distinctions in neuropsychiatry: Insights from schizophrenia and Tourette syndrome

Impairments in social cognition may reflect dysfunction of disorder specific or disorder general mechanisms. Although cross-disorder comparison may prove insightful, few studies have compared social cognition in different neuropsychiatric disorders. Parallel investigation of schizophrenia and Tourette syndrome (TS) is encouraged by similarities including the presence of problematic social behavior, echophenomena, emotional dysregulation and dopamine dysfunction. Focusing on tests of social cognition administered in both disorders, this review aims to summarize behavioral, neurophysiological and neuroimaging findings, before exploring how these may contribute to clinical symptoms. Studies investigating social cognition (imitation, emotion recognition, and understanding of beliefs or intentions) in patients with schizophrenia or TS were identified through Web of Science and PubMed searches. Although findings indicate that social cognitive deficits are more apparent in schizophrenia, adults with TS can exhibit similar task performance to patients with paranoia. In both disorders, behavioral and neuroimaging findings raise the possibility of increased internal simulation of others' actions and emotions, in combination with a relative under-application of mentalizing. More specifically, dysfunction in neurobiological substrates such as temporo-parietal junction and inferior frontal gyrus may underlie problems with self-other distinctions in both schizophrenia and TS. Difficulties in distinguishing between actions and mental states linked to the self and other may contribute to a range of psychiatric symptoms, including emotional dysregulation, paranoia, social anhedonia and socially disruptive urges. Comparing different patient populations could therefore reveal common neuro-cognitive risk factors for the development of problematic social behaviors, in addition to markers of resilience, coping strategies and potential neuro-compensation mechanisms.

miR-219 attenuates demyelination in cuprizone-induced demyelinated mice by regulating monocarboxylate transporter 1

Remyelination is limited in patients with multiple sclerosis (MS) due to the difficulties in recruiting proliferating oligodendrocyte precursors (OPCs), the inhibition of OPC differentiation and/or maturation, and/or failure in the generation of the myelin sheath. In vitro studies have revealed that miR-219 is necessary for OPC differentiation and monocarboxylate transporter 1 (MCT1) plays a vital role in oligodendrocyte maturation and myelin synthesis. Herein, we hypothesized that miR-219 might promote oligodendrocyte differentiation and attenuate demyelination in a cuprizone (CPZ)-induced demyelinated model by regulating the expression of MCT1. We found that CPZ-treated mice exhibited significantly increased anxiety in the open field test. However, miR-219 reduced anxiety as shown by an increase in the total distance, the central distance and the mean amount of time spent in the central area. miR-219 decreased the quantity of OPCs and increased the number of oligodendrocytes and the level of myelin basic protein (MBP) and cyclic nucleotide 3' phosphodiesterase (CNP) protein. Ultrastructural studies further confirmed that the extent of demyelination was attenuated by miR-219 overexpression. Meanwhile, miR-219 also greatly enhanced MCT1 expression via suppression of oligodendrocyte differentiation inhibitors, Sox6 and Hes5, treatment with the MCT1 inhibitor α-cyano-4-hydroxycinnamate (4-CIN) reduced the number of oligodendrocytes and the protein levels of MBP and CNP. Taken together, these results suggest a novel mode of action of miR-219 via MCT1 in vivo and may provide a new potential remyelination therapeutic target.

Oscillatory Synchronous Inhibition in the Basolateral Amygdala and its Primary Dependence on NR2A-containing NMDA Receptors

Synchronous, rhythmic firing of GABAergic interneurons is a fundamental mechanism underlying the generation of brain oscillations, and evidence suggests that NMDA receptors (NMDARs) play a key role in oscillatory activity by regulating the activity of interneurons. Consistent with this, derangement of brain rhythms in certain neuropsychiatric disorders, notably schizophrenia and autism, is associated with NMDAR hypofunction and loss of inhibitory interneurons. In the basolateral amygdala (BLA)-dysfunction of which is involved in a host of neuropsychiatric diseases-, principal neurons display spontaneous, rhythmic "bursts" of inhibitory activity, which could potentially be involved in the orchestration of oscillations in the BLA network; here, we investigated the role of NMDARs in these inhibitory oscillations. Rhythmic bursts of spontaneous IPSCs (0.5 Hz average burst frequency) recorded from rat BLA principal cells were blocked or significantly suppressed by D-AP5, and could be driven by NMDAR activation alone. BLA interneurons generated spontaneous bursts of suprathreshold EPSCs at a similar frequency, which were also blocked or reduced by D-AP5. PEAQX (GluN2A-NMDAR antagonist; 0.4 μM) or Ro-25-6981 (GluN2B-NMDAR antagonist; 5 μM) suppressed the IPSC and EPSC bursts; suppression by PEAQX was significantly greater than that by Ro-25-6981. Immunohistochemical labeling revealed the presence of both GluN2A- and GluN2B-NMDARs on GABAergic BLA interneurons, while, functionally, GluN2A-NMDARs have the dominant role, as suggested by a greater reduction of NMDA-evoked currents by PEAQX versus Ro-25-6981. Entrainment of BLA principal neurons in an oscillatory generation of inhibitory activity depends primarily on activation of GluN2A-NMDARs, and interneuronal GluN2A-NMDARs may play a significant role.

Altered Neural Activity during Irony Comprehension in Unaffected First-Degree Relatives of Schizophrenia Patients-An fMRI Study

Irony is a type of figurative language in which the literal meaning of the expression is the opposite of what the speaker intends to communicate. Even though schizophrenic patients are known as typically impaired in irony comprehension and in the underlying neural functions, to date no one has explored the neural correlates of figurative language comprehension in first-degree relatives of schizophrenic patients. In the present study, we examined the neural correlates of irony understanding in schizophrenic patients and in unaffected first-degree relatives of patients compared to healthy adults with functional MRI. Our aim was to investigate if possible alterations of the neural circuits supporting irony comprehension in first-degree relatives of patients with schizophrenia would fulfill the familiality criterion of an endophenotype. We examined 12 schizophrenic patients, 12 first-degree relatives of schizophrenia patients and 12 healthy controls with functional MRI while they were performing irony and control tasks. Different phases of irony processing were examined, such as context processing and ironic statement comprehension. Patients had significantly more difficulty understanding irony than controls or relatives. Patients also showed markedly different neural activation pattern compared to controls in both stages of irony processing. Although no significant differences were found in the performance of the irony tasks between the control group and the relative group, during the fMRI analysis, the relatives showed stronger brain activity in the left dorsolateral prefrontal cortex during the context processing phase of irony tasks than the control group. However, the controls demonstrated higher activations in the left dorsomedial prefrontal cortex and in the right inferior frontal gyrus during the ironic statement phase of the irony tasks than the relative group. Our results show that despite good task performance, first-degree relatives of schizophrenia patients had alterations in the neural circuits during irony processing. Thus, we suggest that neural alteration of irony comprehension could be a potential endophenotypic marker of schizophrenia.

Decreased functional connectivity in schizophrenia: The relationship between social functioning, social cognition and graph theoretical network measures

Schizophrenia is a complex disorder in which abnormalities in brain connectivity and social functioning play a central role. The aim of this study is to explore small-world network properties, and understand their relationship with social functioning and social cognition in the context of schizophrenia, by testing functional connectivity differences in network properties and its relation to clinical behavioral measures. Resting-state fMRI time series data were acquired from 23 patients diagnosed with schizophrenia and 23 healthy volunteers. The results revealed that patients with schizophrenia show significantly decreased connectivity between a range of brain regions, particularly involving connections among the right orbitofrontal cortex, bilateral putamen and left amygdala. Furthermore, topological properties of functional brain networks in patients with schizophrenia were characterized by reduced path length compared to healthy controls; however, no significant difference was found for clustering coefficient, local efficiency or global efficiency. Additionally, we found that nodal efficiency of the amygdala and the putamen were significantly correlated with the independence-performance subscale of social functioning scale (SFC), and Reading the Mind in the Eyes test; however, the correlations do not survive correction for multiple comparison. The current results help to clarify the relationship between social functioning deficits and topological brain measures in schizophrenia.

Neuro-cognition and social cognition elements of social functioning and social quality of life

Previous studies have shown that deficits in social cognition mediate the association between neuro-cognition and functional outcome. Based on these findings, the current study presents an examination of the mediating role of social cognition and includes two different outcomes: social functioning assessed by objective observer and social quality of life assessed by subjective self-report. Instruments measuring different aspects of social cognition, cognitive ability, social functioning and social quality of life were administered to 131 participants who had a diagnosis of a serious mental illness. Results showed that emotion recognition and attributional bias were significant mediators such that cognitive assessment was positively related to both, which in turn, were negatively related to SQoL. While one interpretation of the data suggests that deficits in emotion recognition may serve as a possible defense mechanism, future studies should re-assess this idea.

Socio-neuro risk factors for suicidal behavior in criminal offenders with psychotic disorders

Relative to the general population, individuals with psychotic disorders have a higher risk of suicide. Suicide risk is also elevated in criminal offenders. Thus, psychotic-disordered individuals with antisocial tendencies may form an especially high-risk group. We built upon prior risk analyses by examining whether neurobehavioral correlates of social cognition were associated with suicidal behavior in criminal offenders with psychotic disorders. We assessed empathic accuracy and brain structure in four groups: (i) incarcerated offenders with psychotic disorders and past suicide attempts, (ii) incarcerated offenders with psychotic disorders and no suicide attempts, (iii) incarcerated offenders without psychotic disorders and (iv) community non-offenders without psychotic disorders. Established suicide risk variables were examined along with empathic accuracy and gray matter in brain regions implicated in social cognition. Relative to the other groups, offenders with psychotic disorders and suicide attempts had lower empathic accuracy and smaller temporal pole volumes. Empathic accuracy and temporal pole volumes were significantly associated with suicide attempts independent of other risk variables. The results indicate that brain and behavioral correlates of social cognition may add incremental value to models of suicide risk.

On the integrity of functional brain networks in schizophrenia, Parkinson's disease, and advanced age: Evidence from connectivity-based single-subject classification

Previous whole-brain functional connectivity studies achieved successful classifications of patients and healthy controls but only offered limited specificity as to affected brain systems. Here, we examined whether the connectivity patterns of functional systems affected in schizophrenia (SCZ), Parkinson's disease (PD), or normal aging equally translate into high classification accuracies for these conditions. We compared classification performance between pre-defined networks for each group and, for any given network, between groups. Separate support vector machine classifications of 86 SCZ patients, 80 PD patients, and 95 older adults relative to their matched healthy/young controls, respectively, were performed on functional connectivity in 12 task-based, meta-analytically defined networks using 25 replications of a nested 10-fold cross-validation scheme. Classification performance of the various networks clearly differed between conditions, as those networks that best classified one disease were usually non-informative for the other. For SCZ, but not PD, emotion-processing, empathy, and cognitive action control networks distinguished patients most accurately from controls. For PD, but not SCZ, networks subserving autobiographical or semantic memory, motor execution, and theory-of-mind cognition yielded the best classifications. In contrast, young-old classification was excellent based on all networks and outperformed both clinical classifications. Our pattern-classification approach captured associations between clinical and developmental conditions and functional network integrity with a higher level of specificity than did previous whole-brain analyses. Taken together, our results support resting-state connectivity as a marker of functional dysregulation in specific networks known to be affected by SCZ and PD, while suggesting that aging affects network integrity in a more global way. Hum Brain Mapp 38:5845-5858, 2017. © 2017 Wiley Periodicals, Inc.