Analysis of VOT in Turkish speakers with aphasia.

Studies investigating voicing onset time (VOT) production by speakers with aphasia have shown that nonfluent aphasics show a deficit in the articulatory programming of speech sounds based on the range of VOT values produced by aphasic individuals. If the VOT value lies between the normal range of VOT for the voiced and voiceless categories, then it is a phonetic distortion, thus a phonetic/articulatory deficit. A number of studies in different languages (French, English, Thai, Taiwanese) have investigated VOT in aphasic subjects in which their VOT values have been compared to those of normal speakers. This study investigates the VOT productions of voiced and voiceless stops by Turkish speakers with aphasia. Six patients with different aetiologies but similar language characteristics participated in this study. The results suggest that although Turkish nonfluent aphasics exhibit unimodal distribution of VOT production, the VOT values and ranges show language-specific properties.