FAS is a speech disorder characterized by changes to the normal speech patterns of the native language. This speech impairment is usually due to stroke or brain injury. Segmental, suprasegmental and prosodic features are altered. FAS speakers’ speech is perceived as foreign rather than disordered. It may be because the speech remains highly accurate and the impairments are generally within the permissible boundaries of the phonological and phonetic variants of the language. In terms of perceptual impression, FAS patients’ speech is placed between speakers with a really foreign accent and the native speaker. Some researchers propose that the impression of foreignness in FAS speakers’ accent may be caused by the listeners misinterpretation of speech markers. Lesions leading to FAS are still not completely understood; some hypothesize that the lesion is small or even down to the size of a single gyrus. New evidence suggests that FAS may be a disorder of the articulate velocity and position maps. The syndrome can be life changing to those affected. Patients report that they are no longer able to recognize themselves speaking a new accent. A whole new persona is born when the accent emerges. This paper presents a review of the syndrome’s features, including its neuropsychological/neuroanatomic aspects, its relationship with AoS and dysarthria, and the syndrome’s psychological implications.

This study presents detailed phonetic and acoustic analyses of the speech characteristics of two new cases of Foreign Accent Syndrome (FAS). Participants include a 48-year-old female who began speaking with an "Eastern European" accent following a traumatic brain injury, and a 45-year-old male who presented with a "British" accent following a subcortical cerebral vascular accident (CVA). Identical samples of the participants' pre- and post-morbid speech were obtained, thus affording a new level of control in the study of Foreign Accent Syndrome. The speech tasks consisted of oral readings of the Grandfather Passage and 18 real words comprised of the stop consonants /p/, /t/, /k/, /b/, /d/, /g/ combined with the peripheral vowels /i/, /a/ and /u/ and ending in a voiceless stop. Computer-based acoustic measures included: 1) voice onset time (VOT), 2) vowel durations, 3) whole word durations, 4) first, second and third formant frequencies, and 5) fundamental frequency. Formant frequencies were measured at three points in the vowel duration: a) 20%, b) 50%, and c) 80% to assess differences in vowel 'onglides' and 'offglides'. The phonetic analysis provided perceptual identification of the major phonetic features associated with the foreign quality of participant's FAS speech, while acoustic measures allowed precise quantification of these features. Results indicated evidence of backing of consonant and vowel productions for both participants. The implications for future research and clinical applications are also considered.