Recognition naming of nouns and verbs in Alzheimer's disease

Twenty right-handed, native English-speakers with Alzheimer's disease (AD) and 14 age- and education-matched control subjects were asked to perform recognition naming tasks with a pictorial target and a written lexical target. They were asked to relate line drawings depicting 20 actions and 20 objects with 20 frequency-matched nouns and verbs. Patients were also asked to name a pictorial target to confrontation. We found that AD patients produced significantly more confrontation and recognition naming errors than controls for verbs and nouns. Planned analyses demonstrated that AD patients were worse at confrontation naming than their own recognition naming with a pictorial target. In addition, individual patient analyses revealed that most AD patients were more impaired in their confrontation naming with verbs than with nouns and were more impaired at recognition naming with verbs than with nouns. We hypothesize a two-component model of verb naming difficulty. Thus, the distinct patterns of semantic organization associated with concepts underlying verbs curd nouns and the relative difficulty in confrontation naming compared io recognition naming both contribute to AD patients' verb naming difficulties.