Outcome Of Clinical High-risk Of Psychosis And Its Neuropsychological Mechanisms On Social Cognition Deficits

[Background and Objective] Unlike many other chronic medical diseases, such as diabetes or hypertension, schizophrenia and other psychotic disorders most often begin in young adulthood, remain undetected and untreated for longer periods of time, and are often associated with functional decline. Early detection and intervention offer the hope of improving the impact of these disorders on young lives. The current study set out to identify of a Chinese sample with clinical high risk(CHR) of psychosis, determine the characteristics of clinical outcome, social cognition and eye-track patterns.[Method] This study has three parts. The first part is about the clinical outcome. A total of 117 CHR participants were followed for at least 2 years. The presence of CHR was determined at the participants’ first visit to the Shanghai Mental Health Center(SMHC), based on their responses to the Structured Interview for Prodromal Syndromes(SIPS). Baseline demographic and clinical data were assessed as possible predictors of psychosis. The second part is about the social cognition. Fifty CHR participants identified through the SIPS and 52 age-education-matched controls were assessed with a complete standard neuropsychological battery(the MCCB, MATRICS Consensus Cognitive Battery) and social cognition assessments(Faux Pas Test and Reading Mind from Eyes Test). Baseline social cognition data were assessed as possible predictors of psychosis. The third part is about the eye-track. Forty CHR participants identified through the SIPS and 40 age-education-matched controls were assessed with eye track system by eyelink 2000. We designed two social interactive eye movement experiments("emotional face identificaiton" and “Cartoon Story Sequencing") and the data of fixation and saccade were recorded and analyzed by comparing with CHR and healthy controls.[Results] In the first part of results from this study, we found that during the time between the initial assessment and the follow-up(a mean period of 28.3 months), out of the 117 CHR participants, 86(73.5%) completed the follow-up. Twenty-five(29.1%) had transitioned to a psychotic disorder. The conversion subgroup had a lower level of functioning, a higher total score of SIPS positive symptoms, longer duration of untreated prodromal symptoms(DUPS), and more initial diagnoses of, or prescribed medicines for, psychotic issues at baseline. In the second part of results from this study, compared with controls, the CHR group showed significantly poorer performances on social cognition tests and most MCCB domains. Moreover, they were significantly slower and poorer accuracy in interpreting positive and neutral eye expressions than healthy controls. Significant positive correlations were found between faux pas detection and the MCCB domains of Attention/Vigilance and Working Memory in CHR participants when controlling for age and years of education. Social cognition tests in those converters who were diagnosed with full-blown psychosis within 12 months were lower than they were for non-converters. In the third part of results from this study, we found that compared with controls, CHR subjects showed less frequency of fixation and saccade, longer fixation duration and smaller saccade amplitude. Also, the dwell time that spend in person-related information in pictures, fixation and run out counts in person-related area were much less in CHR subjects compared with controls.[Conclusions] In summary, the present findings provide evidence showing that the CHR participants could be identified in an Eastern society and that the transition rate found in the two-year follow-up is very close to what appears in the literature from other countries. Several factors, such as functional impairments, the severity of overall positive symptoms, DUPS, and clinical judgments of psychosis, maybe helpful in predicting which CHR participants are more likely to develop full psychosis. Our data contribute to the evidence that being able to correctly interpret the mental state of others from their eyes is impaired in youths with prodromal psychotic syndromes. Impairments in social cognition ability are acquired earlier in the prodromal stage of psychosis, along with general cognition(such as memory function et al.) deficits and can predict prodromal symptom relapse and deterioration. This study provides the first data showing that CHR youths have more difficulty in decoding the positive and neutral mental states of others, compared to negative states. The current study explicitly describes that CHR subjects showed two eye track patterns during the process of social cognition: "a limited scanpath pattern" and "a scattered gaze pattern". Those patterns may contribute to the dificits of social cognition in CHR subjects and caused by changing the way of information gattering and processing.