Interpretation of ambiguous idiomatic statements in schizophrenic and depressive patients. Evidence for common and differential cognitive patterns

Background: This study is concerned with the comprehension of ambiguous idiomatic statements in schizophrenic and depressive patients. Aims: Using a multiple choice procedure,we simultaneously tested the presence of concrete and literal elements in the understanding of idiomatic statements. Method: Fourteen schizophrenic and 10 patients undergoing a major depressive episode as well as 14 control subjects completed a questionnaire with 10 idiomatic expressions with two possible interpretations (figurative and literal) of equivalent prominence. The participants had to choose one word linked with the different interpretations of these idioms (figurative, literal, concrete or inappropriate meaning). Results: The main results show that, in all the subjects, the contextual characteristics of the task induced a bias in favor of figurative interpretations despite the equivalent prominence of the literal interpretations of the idioms. The selection of responses relating to the concrete meaning of a single word in the idiom constituted a response mode common to both the schizophrenic and depressed patients. Despite the contextual constraints of the task, the schizophrenics opted for the literal responses more often than the other participants. The descriptive analysis argues in favor of a cognitive and clinical heterogeneity of schizophrenic patients. Conclusion: Results support the idea that literality and concreteness in idiomatic interpretation are possibly due to distinct cognitive impairments, though only some are specific to schizophrenic patients. Copyright (c) 2006 S. Karger AG, Basel.