Noun–verb ambiguity in chronic undifferentiated schizophrenia

Abstract

This study investigated noun–verb retrieval patterns of 30 adults with chronic undifferentiated schizophrenia and 67 typical adults, to determine if schizophrenia affected nouns (associated with temporal lobe function) differently from verbs (associated with frontal lobe function). Stimuli were homophonic homographic homonyms, balanced according to frequency of occurrence, where N > V, N < V, or N ≈ V. Systematicity effects, in which systematic noun and verb meanings are transparently related (e.g., “drain”), and unsystematic noun and verb meanings appear to be unrelated (e.g., “seal”), were also examined. Adults with schizophrenia overselected nouns, in both phrase and sentence tasks. Typical participants strongly preferred verbs in the phrase task, but nouns in the sentence task. Frequency of occurrence yielded statistically significant effects in control, but not in experimental groups. Effects of systematicity were statistically significant in some, but not all tasks and conditions. Age of typical participants was not significant. Learning outcomes: Readers will be introduced to (a) evidence of noun-verb organization in the brain; (b) evidence of ambiguous noun-verb preference to differentiate the language of schizophrenia from the language of typical adults; and (c) evidence of ambiguous noun-verb preference to differentiate the language of schizophrenia from fluent aphasia.