Predictive Inference Alterations in Psychosis Proneness Show Task-Dependent Signatures.

Perception relies on the dynamic integration of sensory inputs with prior expectations shaped by recent experience. Disruptions in this inferential process are thought to underlie psychosis, yet whether similar alterations occur in subclinical psychosis-like experiences (PLEs) and how they manifest across perceptual contexts remain unclear. Here, we tested two independent samples of healthy adults: 80 performed a visual detection task and 62 a motion discrimination task. Mixed-effects models revealed that higher PLE scores predicted reduced weighting of sensory evidence and greater reliance on probabilistic cues across tasks. Complementary signal detection analyses confirmed that higher PLE scores were associated with reduced perceptual sensitivity, alongside increased cue-dependent response bias shifts. To capture how recent experience shapes perception, we quantified history biases: the influence of the previous stimulus or choice on current decisions. These biases diverged across contexts: in the detection task, the repulsive bias from the previous stimulus was attenuated in high-PLE individuals, whereas in the discrimination task, they exhibited a repulsive bias away from previous choices. These task-dependent signatures reveal that psychosis-like traits differentially alter the use of past information, pointing to a broader inferential vulnerability along the psychosis continuum.