Segmental Phonology of Bilingual Nigerian Adult Wernicke’s Aphasics

Abstract

Research on the phonology of aphasia has been mainly on the language of aphasics who are first language speakers. Only few studies on Nigerian aphasics have been concerned with linguistic analysis. This situation is quite unhealthy for the treatment and rehabilitation of Nigerian aphasics. Therefore, this paper examined the segmental phonology of bilingual Nigerian Wernicke's aphasics to provide explanation for the noticeable patterns of their phonology. Ten bilingual Nigerian adult Wernicke's aphasics from a Nigerian teaching hospital were purposively sampled. They were both in-patients and out-patients. Their speeches were tape-recorded. The data were subjected to perceptual analysis, complemented with frequency count and simple percentage. Three major forms of deviation were identified at the segmental level of the speech of the subjects: deletion, substitution, and epenthesis, with deletion being the most prominent, followed by substitution. The deviation identified affected consonants more than vowels. The brain damage affected plosives and alveolars more than any other class of sound. There was no consistent pattern of the way the deviation forms affected vowels. Optimality Theory was used to explicate the way constraints were ranked by the subjects. Generally, the subjects ranked markedness above faithfulness.