Neural correlates of conversational turn-taking perception in individuals at clinical high-risk for psychosis

Background: Impaired social functioning is a core feature of individuals at clinical high-risk (CHR) for psychosis and strongly predicts poor outcomes. One essential component of everyday communication that may be disrupted in this population is conversational turn-taking. While atypical turn-taking has been documented in CHR behaviorally, the neural mechanisms underlying these disruptions in CHR remain underexplored. Methods: Using electroencephalogram (EEG), participants passively listened to brief, recorded conversations in which one speaker made a request and the other responded following a short (200 ms) or long (700 ms) inter-speaker gap. The final sample included 24 CHR individuals (M = 20.6 years, 62.5 % male) and 32 healthy controls (HC; M = 21.7 years, 40.6 % male). Results: ERP amplitudes during the long inter-speaker gap did not significantly differ between groups, t(50) = –1.49, p = .14, g = -0.40. However, HCs exhibited significantly negative amplitudes relative to zero, t(31) = –4.12, p < .001, g = -0.71, whereas CHR individuals did not, t(23) = –1.63, p = .12, g = -0.32. Following the speaker's response, a main effect of gap length was observed, F(1, 54) = 15.73, p < .001, ges = 0.12, such that P2/P3 amplitudes were larger following long gaps relative to short gaps, with no significant interaction or main effect of group. Weaker modulation of P2/P3 amplitude was associated with greater social anhedonia, r(54) = –0.28, p = .040. Conclusions: Disrupted perception of turn-taking in CHR may reflect impairments in social communication, providing insight into social anhedonia and potential neural markers of psychosis risk.