Perseveration in aphasia.

We developed a battery of tests to evaluate the relationship of perseveration to aphasia, and tested 44 subjects (18 with aphasia, 13 with right hemispheric lesions, 13 normal controls). Several major findings emerged: left hemispheric, posteriorly located, aphasia producing lesions also produced abundant perseverations, both verbal and non-verbal, which were primarily recurrent in type; right hemispheric lesions produced few perseverations, and these were primarily of the continuous type; more than half of the verbal recurrent perseverations of aphasia on a naming task were semantic in nature. We conclude that recurrent perseveration has a special, perhaps integral, link to language disorders of aphasia, particularly fluent aphasia associated with posterior lesions.