Introduction: Anomia is an impairment of naming: the retrieval of specific lexical items from the mental lexicon. Theoretically, whether anomia reflects a failure of selection at the preverbal "idea" level or at the subsequent linguistic formulation stage remains a topic of debate. We investigated the preverbal mechanism of idea selection for sentence generation, which requires the selection of a proposition from among competing alternatives during message formulation, in patients with severe anomia.
Method: Patients with lesions to the left temporal lobe (N = 12), presenting with clinically defined anomia, and matched healthy controls (N = 24) completed sentence-level tasks that required the oral generation of a sentence or single word when presented with a word, a word pair, or a sentence. Selection demands were manipulated so that the stimuli activated many competing response options (low constraint) or one dominant or few response options (high constraint).
Results: There was no effect of stimuli constraint in the patient group that differed from that in the healthy control group on any of the generation tasks, suggesting that idea-level selection is intact in the patient group.
Conclusions: These findings have implications for theoretical models of spoken language production and for clinical treatments of anomia.
Keywords: Anomia; message formulation; selection; sentence generation; spoken language production.