Voice Onset Time Imitation in Teens Versus Adults.

Area of Science:

• Phonetics and Speech Science
• Developmental Psychology
• Acoustic Phonetics

Background:

• Investigating age-based differences in phonetic acquisition is crucial for understanding speech development.
• Previous research suggested potential age-related advantages in phonetic imitation, possibly linked to imitative ability.
• The role of explicit imitation versus perception in phonetic learning requires further examination.

Purpose of the Study:

• To compare the imitative abilities of teenagers and adults in producing sentences with manipulated voice onset time (VOT).
• To determine if age-based differences in imitative capacity underlie purported advantages in phonetic acquisition.
• To assess the relationship between imitation and perception of VOT variations across age groups.

Main Methods:

• Participants included 39 teenagers (mean age 13) and 31 adults.
• An explicit imitation and discrimination task involved sentences with canonical and manipulated (shortened/lengthened) VOT.
• Acoustic metrics (ΔVOT, Proximity) and discrimination accuracy were used to assess imitation and perception.

Main Results:

• Both teenagers and adults successfully imitated VOT manipulations in both shortened and lengthened directions.
• Adults exhibited significantly greater VOT lengthening (higher ΔVOT) and closer proximity to target stimuli than teenagers.
• Above-chance discrimination accuracy was observed in both groups, with a significant perception-production link for lengthened VOT.

Conclusions:

• Contrary to hypotheses, adults showed significantly more imitation than teenagers, challenging age-based advantages in imitative ability.
• Robust imitation of VOT changes was observed in both age groups, including for shortened VOT, contrasting prior findings.
• Individual perceptual performance partially predicted imitation extent, highlighting the influence of other factors on imitative variation.