A disturbance in the conceptual organization of actions in patients with ideational apraxia.

Patients with ideational apraxia (i.a.) performed significantly worse than patients without i.a. in a task where they had to arrange pictures in correct order illustrating actions requiring the use of various objects. There was no influence of severity of aphasia nor presence or severity of ideomotor apraxia. In two similar pictorial tasks, where consecutive stages of common events are illustrated, which, however, did not include manipulation of objects, there was no difference in performance of patients with and without i.a. It is concluded that i.a. is a disturbance in the conceptual organization of actions.