Auditory perceptual biases, such as a tendency to hear things differently, are linked to anomalous self-experiences, especially feeling alienated from one's surroundings and emotional numbing, in people with first episode psychosis and healthy controls. No link was found between metacognitive efficiency and anomalous experiences. The findings support the minimal self-disturbance model of schizophrenia spectrum vulnerability, particularly the idea of hyperreflexivity.
People in the early stages of psychosis show a reduced ability to accurately evaluate their own perceptions, a metacognitive deficit. In a perceptual decision-making task, individuals with first-episode psychosis performed worse on metacognitive accuracy than healthy controls, even when their basic perceptual performance was accounted for. Grey matter volume was also reduced in the superior frontal gyrus, a brain region linked to metacognition. However, no direct relationship was found between grey matter volume and metacognitive accuracy, leaving the neural basis of this deficit unclear. These findings suggest that a specific problem in scrutinizing one's own perceptions may underlie later functional difficulties in schizophrenia.