ASSESSMENT OF THE BRADYPHRENIA OF PARKINSONISM - A NOVEL USE OF DELAYED AUDITORY-FEEDBACK

Sufferers from parkinsonism have difficulty shifting or developing an appropriate mental set. Delayed auditory feedback may, therefore, disr upt their speech more than that of healthy controls. This was the case when 104 subjects with idiopathic parkinsonism and 144 without were c ompared. Moreover, the disruptive effect was complementary, in discrim inating between those with and without clinical parkinsonism, to the r esponse in reaction time to a warning. Unlike the latter, the disrupti on caused by delayed auditory feedback appeared independent of mental test score results and uninfluenced by consumption of tobacco or anti- parkinsonian therapy. Neither were influenced by a rating of affect. M ore precise delineation of the mental disorders of parkinsonism is nee ded in clinical practice, set against background information on progno sis and drug responsiveness.