Perception of Temporal Structure of Speech in Parkinson's Disease (PD)
It is well known that individuals with idiopathic Parkinson's disease (lPD) present with speech production difficulties. There is mounting evidence that speech perception specifically related to prosody can also be impaired in some of these individuals. Prosody is the information conveyed by the pitch, amplitude and duration patterns of speech. The duration component, which relates to the temporal processing of the brain, seems to be the main contributor to the speech perception impairment. However, research into this problem is fairly limited and has remained mostly inconclusive.
While receptive speech difficulties are not among the most visible or debilitating symptoms of lPD, one important reason for studying them is that they further undermine communicative competence. A better understanding of these difficulties, in conjunction with studies on speech- and non-speech motor impairment, may contribute to a more complete picture of the pathophysiology of lPD, At the clinical level the research can contribute to early detection of lPD, monitoring of disease progression, and monitoring of symptom severity for medication and dosage adjustment purposes.
We propose to perform a preliminary investigation into the temporal processing abilities of IPD patients when they are optimally medicated as compared to a matched control group. The proposed study complements studies reported in the literature by (i) performing a series of perception tests that cover a wide range of prosodic contrasts; (ii) using state-of-the-art speech modification techniques to "surgically" manipulate prosodic dimensions; and (iii) relating these results to results from parallel speech production tasks.