The investigation of cognitive biases has considerably broadened our understanding of the cognitive underpinnings of schizophrenia. This is the first study to investigate the illusory truth or validity effect in schizophrenia, which denotes the phenomenon that the renewed exposure to difficult knowledge questions shifts responses toward affirmation. We hypothesized an excess of the truth effect in schizophrenia, which may play a role in the maintenance of the disorder, particularly relating to positive symptoms.
