Identity recognition from faces and bodies in schizophrenia spectrum disorders.

Deficits in facial identity recognition and its association with poor social functioning are well documented in schizophrenia, but none of these studies have assessed the role of the body in these processes. Recent research in healthy populations shows that the body is also an important source of information in identity recognition, and the current study aimed to thoroughly examine identity recognition from both faces and bodies in schizophrenia. Sixty-five individuals with schizophrenia and forty-nine healthy controls completed three conditions of an identity matching task in which they attempted to match unidentified persons in unedited photos of faces and bodies, edited photos showing faces only, or edited photos showing bodies only. Results revealed global deficits in identity recognition in individuals with schizophrenia (ηp2 = 0.068), but both groups showed better recognition from bodies alone as compared to faces alone (ηp2 = 0.573), suggesting that the ability to extract useful information from bodies when identifying persons may remain partially preserved in schizophrenia. Further research is necessary to understand the relationship between face/body processing, identity recognition, and functional outcomes in individuals with schizophrenia-spectrum disorders.

Preliminary evidence for the efficacy of single-session transcranial direct current stimulation to the ventrolateral prefrontal cortex for reducing subclinical paranoia in healthy individuals.

OBJECTIVES: Paranoia manifests similarly in subclinical and clinical populations and is related to distress and impairment. Previous work links paranoia to amygdala hyperactivity and reduced activation of the ventrolateral prefrontal cortex (VLPFC), a region thought to regulate amygdala activity. METHODS: This study aimed to reduce subclinical paranoia in 40 undergraduates by increasing activity of the VLPFC via single-session transcranial Direct Current Stimulation (tDCS). A double-blind, crossover (active vs. sham stimulation) design was used. RESULTS: Paranoia significantly decreased after active stimulation (dz  = 0.51) but not sham (dz  = 0.19), suggesting that tDCS of VLPFC was associated with mean-level reductions in paranoia. CONCLUSION: These findings demonstrate preliminary support for the role of single-session active stimulation to the VLPFC for reducing subclinical paranoia in healthy individuals. PRACTITIONER POINTS: In both clinical and subclinical populations, paranoia is related to distress and poorer functional outcomes. Paranoia has been linked to overactivation of the amygdala, a brain region responsible for detecting salience and threat, and reduced activation of the ventrolateral prefrontal cortex (VLPFC), a region thought to modulate and regulate amygdala activity. In this study, transcranial direct current stimulation (tDCS) of the VLPFC reduced self-reported paranoia in healthy undergraduate students. tDCS may be a promising intervention for reducing paranoia in subclinical and clinical populations. Effects were relatively small and require replication with larger subclinical samples and with clinical samples.

Implicit and explicit processing of bodily emotions in schizophrenia.

INTRODUCTION: Disturbed emotion processing is well documented in schizophrenia, but the majority of studies evaluate processing of emotion only from facial expressions. Social cues are also communicated via body posture, and they are similarly relevant for successful social interactions. The aim of the current study was to thoroughly examine body perception abilities in individuals with schizophrenia. METHODS: Fifty-nine patients with schizophrenia and 37 healthy controls completed two tasks of body processing. The first, which was based on the Affect Misattribution Procedure, evaluated implicit processing of bodily emotions, and the second utilised a traditional emotion identification paradigm to assess explicit emotion recognition. RESULTS: Results revealed aberrant implicit processing, but more normative explicit processing, in individuals with schizophrenia. Moderate associations were found between processing of bodies and symptoms of paranoia. Performance on the tasks was not related to cognitive functioning but was associated with clinician-rated social functioning. CONCLUSIONS: Collectively, these results provide information about disturbed processing of bodily emotions in schizophrenia and suggest that these disturbances are associated with the severity of positive symptoms and predict difficulties in everyday social activities and interpersonal relationships.