Difficulties in understanding irony and sarcasm are part of the social cognition deficits in patients with schizophrenia. A number of studies have reported higher error rates during comprehension in patients with schizophrenia. However, the relationships of these impairments to schizotypal personality traits and other language deficits, such as the comprehension of proverbs, are unclear. We investigated irony and proverb comprehension in an all-female sample of 20 schizophrenia patients and 27 matched controls. Subjects indicated if a statement was intended to be ironic, literal, or meaningless and furthermore rated the meanness and funniness of the stimuli and certainty of their decision. Patients made significantly more errors than controls did. Globally, there were no overall differences in the ratings. However, patients rated the subgroup of stimuli with answers given incorrectly as having significantly less meanness and in case of an error indicated a significantly higher certainty than controls. Across all of the study participants, performances in irony ( ) and proverb ( ) comprehension were significantly correlated with schizotypal personality traits, suggesting a continuum of nonliteral language understanding. Because irony is so frequent in everyday conversations, this makes irony an especially promising candidate for social cognition training in schizophrenia. 1. Background Defective appraisal of the intention of others and difficulties with language are hallmark features of psychopathology in schizophrenia. Social cognition deficits have been previously identified and are currently being extensively researched. The results show that deficits in social cognition are relevant to real-world functioning and outcome . Training of social cognitive skills has gained increasing interest in schizophrenia therapy. In this context, the comprehension of ironic remarks by patients with schizophrenia has become a research focus both as an outcome measure and as a training goal [1–5]. This is obvious, considering that the decision on whether a remark made by others is intended to be ironic or not is slightly artificial, but is instead required routinely in everyday interaction. Everyone is familiar with irony. It is remarkably frequently used, as shown by linguistic research [6, 7]. For example, Gibbs  showed that 1 out of 8 conversational turns in an everyday communication among college students was ironic. In the case of linguistic irony (which alone is discussed here), an ironic expression is usually incorrect and often the opposite of what the
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