Perturbed sensory memory associated with schizotypy symptom load

Impaired auditory event-related potential (ERP) components, including the N100 and MMN, are linked to sensory signatures of schizophrenia. Nonclinical individuals with schizophrenia-like traits (schizotypy) provide an attractive model for investigating these ERP biomarkers, as the individuals exhibit similar traits without clinical confounds (e.g., medications). The driving theoretical framework is that there is a continuum of traits that extends from the nonclinical population to patients diagnosed with schizophrenia spectrum disorders (SSD). Here, we tested the prediction that nonclinical participants high in schizotypy traits would also exhibit impaired N100 and MMN responses, reflecting impairment in early auditory processing, and/or in predicting sensory inputs. We used a simple odd-ball pitch-deviant paradigm and compared ERP amplitudes across a sample of healthy participants who completed the Schizophrenia Personality Questionnaire - Brief Revised (SPQ-BR). Participants with high total scores (high schizotypy; N = 25) were compared to middle-scoring scorers (controls; N = 32). We then investigated more nuanced relationships between ERP components and factors of the SPQ-BR (cognitive-perceptual, interpersonal, disorganized). High schizotypy exhibited prolonged MMN latencies but intact amplitudes-a pattern also observed in those with elevated negative symptoms. However, attenuated deviant N100 amplitudes were associated with higher disorganized factor scores, whereas standard and MMN amplitudes were not. Importantly, these data suggest that early deviance detection and predictive sensory memory mechanisms are differentially perturbed with schizotypy symptom load. Further research into schizotypy traits is required to validate the population for SSD risk. In conclusion, auditory impairments can be identified in nonclinical schizotypy and leveraged to understand disorder-related processes.