title: Second formant transitions in fluent speech of persistent and recovered preschool children who stutter.
abstract: This study investigated frequency change and duration of the second formant (F2) transitions in perceptually fluent speech samples recorded close to stuttering onset in preschool age children. Comparisons were made among 10 children known to eventually persist in stuttering, 10 who eventually recovered from stuttering, and 10 normally fluent controls. All were enrolled in the longitudinal Stuttering Research Project at the University of Illinois. Subjects fluently repeated standard experimental sentences. The same 36 perceptually fluent target segments (syllables embedded in words) from each subject's repeated sentences were analyzed. The syllables were divided into three phonetic categories based on their initial consonant: bilabial, alveolar, and velar placement. The frequency change and duration of F2 transitions were analyzed for each of the target CV segments. F2 transition onset and offset frequencies and their interval (duration) were measured for each utterance. Data indicate that near stuttering onset, children whose stuttering eventually persisted demonstrated significantly smaller frequency change than that of the recovered group. It is suggested that the F2 transitions should continue to be investigated as a possible predictor of stuttering pathways.
  
  
  OBJECTIVE
  (1) Readers will learn about studies regarding second formant transition related to stuttering. (2) Readers will learn about differences between children who persist in stuttering and those who recover from stuttering. (3) Readers will learn about research concerned with early identification of risk criteria in persistent stuttering.
authors.affiliation: University of Illinois, Speech and Hearing Science, 901 S. Sixth Street, Champaign, IL 61820, USA.
authors.forename: Anu
authors.initials: A
authors.lastname: Subramanian
authors.forename: Ehud
authors.initials: E
authors.lastname: Yairi
authors.forename: Ofer
authors.initials: O
authors.lastname: Amir
mesh_terms: D002675:Child, Preschool; D018572:Disease-Free Survival; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D015588:Observer Variation; D010700:Phonetics; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D013018:Sound Spectrography; D013067:Speech Perception; D013342:Stuttering / Q000175:diagnosis* / Q000453:epidemiology / Q000628:therapy