VERBAL FLUENCY IN PARKINSONS-DISEASE

This study compares the performance of Parkinson's disease patients with age-matched controls on semantic and letter-initial verbal fluency tests. An analysis of variance revealed that Parkinsonian patients showed impaired word production. However when the covariates of age, present verbal ability (Mill Hill Synonyms) and severity of depression (Geriatic Depression Screening Scale) were included in an analysis of cavariance, the significant effect of Parkinson's disease on verbal fluency disappered. Instead, age and present verbal ability were revealed to the significant sources of between subject variation in total verbal fluency peerformance; results indicated that increased age and lower present verbal ability resulted in poorer performance on the verbal fluency tests. Depression score was not a significant source of between subject variation. The results are discussed in relation to those recently reported by Gurd and Ward (1989). © 1990.