Cross-talker lexical tone discrimination in infancy.

Area of Science:

• Developmental Psychology
• Linguistics
• Auditory Perception

Background:

• Infants must learn to perceive speech despite variations in talker characteristics.
• Lexical tone perception is crucial for tonal languages like Cantonese.
• Understanding developmental changes in cross-talker variability perception is key.

Purpose of the Study:

• To investigate developmental changes in infants' perception of native lexical tones across different talkers.
• To examine the influence of task demands on lexical tone discrimination in infants.
• To identify potential U-shaped developmental trajectories in cross-talker variability perception.

Main Methods:

• Habituation-based visual fixation procedures were used to test Cantonese-learning infants.
• Infants were exposed to Cantonese Tone 1 and Tone 3 produced by single or multiple talkers.
• Age groups tested included 12, 18, and 24-month-olds, with varying task demands.

Main Results:

• 12- and 24-month-olds discriminated tones across talkers, but 18-month-olds did not.
• 18-month-olds could discriminate tones across talkers when a novel object referent was present.
• A U-shaped developmental pattern and perceptual asymmetry were observed in cross-talker tone discrimination.

Conclusions:

• Infant lexical tone perception across talkers follows a U-shaped developmental path.
• Task demands and referential context significantly impact 18-month-olds' cross-talker tone discrimination.
• Perceptual asymmetry exists in the development of native lexical tone discrimination across talkers.