title: Perception of speech modulation cues by 6-month-old infants.
abstract: OBJECTIVE
  The capacity of 6-month-old infants to discriminate a voicing contrast (/aba/-/apa/) on the basis of amplitude modulation (AM) cues and frequency modulation (FM) cues was evaluated.
  
  
  METHODS
  Several vocoded speech conditions were designed to either degrade FM cues in 4 or 32 bands or degrade AM in 32 bands. Infants were familiarized to the vocoded stimuli for a period of either 1 or 2 min. Vocoded speech discrimination was assessed using the head-turn preference procedure.
  
  
  RESULTS
  Infants discriminated /aba/ from /apa/ in each condition; however, familiarization time was found to influence strongly infants' responses (i.e., their preference for novel vs. familiar stimuli).
  
  
  CONCLUSIONS
  Six-month-old infants do not require FM cues and can use the slowest (< 16 Hz) AM cues to discriminate voicing. Moreover, 6-month-old infants can use AM cues extracted from only 4 broad-frequency bands to discriminate voicing.
authors.forename: Laurianne
authors.initials: L
authors.lastname: Cabrera
authors.forename: Josiane
authors.initials: J
authors.lastname: Bertoncini
authors.forename: Christian
authors.initials: C
authors.lastname: Lorenzi
mesh_terms: D000161:Acoustic Stimulation / Q000379:methods; D003463:Cues; D005260:Female; D006309:Hearing; D006801:Humans; D007223:Infant; D008297:Male; D010700:Phonetics; D011930:Reaction Time; D013061:Speech Acoustics; D013067:Speech Perception; D014831:Voice