Intonation Processing In Individuals With Parkinson\u27s Disease

Parkinson\u27s disease is a progressive neurodegenerative disease caused by the death of dopaminergic neurons in structures that make up the basal ganglia. Previous research has shown that damage to the basal ganglia can result in deficient (Cheang et al, 2004; Ma et al, 2007) production and perception of intonation in non-emotional (Cheang et al., 2004; Ma et al., 2007) and emotional (e.g., Breitenstein et al., 1998; Cancelliere & Kertesz, 1990) contexts. Studies on perception have shown evidence that individuals with Parkinson\u27s disease have difficulty discriminating intonation patterns when compared to healthy controls, and that these difficulties are due to higher level processing. In contrast studies on production have shown that difficulties though present are due to motor based deficits associated with Parkinson\u27s disease. The purpose of this study was to determine whether the basis of the intonation processing problems for patients with Parkinson\u27s disease is related to linguistic or non-linguistic factors. The main objectives of the study were to determine if the production deficits were solely motor based, or if, like the perceptual deficits, there was a higher-level processing component. Thirteen patients with Parkinson\u27s disease and 11 healthy controls participated in the study and performed perceptual and production tasks. The perception and production tasks contained non-emotional and emotional stimuli. The perceptual data included participant response, to determine if the results were greater than chance. The production data were analyzed according to pitch range and duration. Significant results were found for the production of happy utterances and questions. These results indicate that likely the production deficits associated with Parkinson\u27s disease are motor based and not due to higher level processing as no significance was found in the perceptual data