The role of the striatum in phonological processing. Evidence from early stages of Huntington’s disease
In Experiment 1 we used a same–different task with isolated words to evaluate whether phoneme perception is intact in HD. In Experiment 2 a word detection task in phrasal contexts allowed for assessing both phoneme perception and perceptual compensation for the French regressive assimilation rule. Results showed that HD patients have normal performance with both phoneme perception in isolated words and regressive assimilation rules. However, in phrasal contexts they display reduced abilities of phoneme discrimination.
These findings challenge the striatum-rule claim and suggest a more fine-grained function of striatal structures in linguistic rule processing. Alternative explanatory frameworks of the striatum-language link are discussed.