title: Mismatch negativity responses in children with a diagnosis of childhood apraxia of speech (CAS).
abstract: OBJECTIVE
  To evaluate whether a hypothesis suggesting that apraxia of speech results from phonological overspecification could be relevant for childhood apraxia of speech (CAS).
  
  
  METHODS
  High-density EEG was recorded from 5 children with CAS and 5 matched controls, ages 5-8 years, with and without CAS, as they listened to randomized sequences of CV syllables in two oddball paradigms: phonemic (/ba/, /pa/) and allophonic (/pa/, /p(h)a/).
  
  
  RESULTS
  In the phonemic contrast condition, mismatch negativity (MMN) responses to oddball sounds were observed for the typically developing (comparison) group but not the CAS group, although a component similar to an immature mismatch response was apparent. The allophonic contrast did not elicit MMN responses in the comparison group, but in the CAS group, an MMN-like response was observed.
  
  
  CONCLUSIONS
  The authors propose that these preliminary findings are consistent with a view of CAS as a disorder that not only affects motor planning but also has a phonological component.
authors.affiliation: Teachers College, Columbia University, New York, NY, USA. kf2119@columbia.edu
authors.forename: Karen
authors.initials: K
authors.lastname: Froud
authors.forename: Reem
authors.initials: R
authors.lastname: Khamis-Dakwar
mesh_terms: D000161:Acoustic Stimulation / Q000379:methods; D001072:Apraxias / Q000503:physiopathology*; D001921:Brain / Q000502:physiology*; D002648:Child; D002675:Child, Preschool; D004566:Electrodes; D004569:Electroencephalography; D005072:Evoked Potentials, Auditory / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D010700:Phonetics; D010865:Pilot Projects; D013064:Speech Disorders / Q000503:physiopathology*; D013067:Speech Perception / Q000502:physiology*