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 is most often caused by damage to the brain caused by a stroke or traumatic brain injury. Other causes have also been reported including multiple sclerosis and conversion disorder and in some cases no clear cause has been identified.

Illustration of Georg Herman Monrad-Krohn in white coat in hospital wing.
Norwegian neurologist Georg Herman Monrad-Krohn reported the best-known 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 (i.e. bike for pike)
  • Trouble with consonant clusters
  • Vowel distortions, prolongations, substitutions (i.e. “yeah” pronounced as “yah”)
  • “uh” inserted into words