Foreign Accent Syndrome (FAS)


This website is designed to provide support to those seeking information about a rare speech disorder called Foreign Accent Syndrome (FAS).

What is Foreign Accent Syndrome (FAS)?

Foreign accent syndrome (FAS) is speech disorder that causes a sudden change to speech so that a native speaker is perceived to speak with a “foreign” accent. FAS can occur from damage to the brain such as stroke or traumatic brain injury. In other cases, FAS can occur as a type of functional neurological disorder (FND) in which speech is affected without clearly observable brain insult. One way of thinking about it is that the first type of FAS (neurogenic) results from brain “hardware” issues, and the second type (functional) from “software” problems. In addition, there are “mixed” cases in which individuals have both neurogenic and functional speech challenges.

Illustration of Georg Herman Monrad-Krohn in white coat in hospital wing.
Norwegian neurologist Georg Herman Monrad-Krohn (1884 – 1964) reported a famous case of Foreign Accent Syndrome.

Speech may be altered in terms of timing, intonation, and tongue placement so that is perceived as sounding foreign. Speech remains highly intelligible and does not necessarily sound disordered.

FAS has been documented in cases around the world, including accent changes from Japanese to Korean, British English to French, American-English to British English, and Spanish to Hungarian.

Some common speech changes associated with FAS include:

  • Fairly predictable errors
  • Unusual prosody, including equal and excess stress (especially in multi-syllabic words)
  • Consonant substitution, deletion, or distortion
  • Voicing errors (e.g., “bike” for “pike”)
  • Trouble with consonant clusters
  • Vowel distortions, prolongations, substitutions (e.g.,“yeah” pronounced as “yah”)
  • “uh” inserted into words