Developmental change in children's speech processing of auditory and visual cues: An eyetracking study.

Area of Science:

• Developmental Psychology
• Speech Perception
• Auditory-Visual Speech Processing

Background:

• Young children show success in visual speech tasks, yet struggle with explicit speech processing measures.
• A gap exists between visual speech processing abilities and explicit behavioral measures in children.
• Understanding word recognition relies on integrating auditory and visual speech cues.

Purpose of the Study:

• To investigate how children (2-8 years) and adults recognize words using auditory and visual speech.
• To bridge the gap between visual-looking task successes and explicit behavioral measures in children's speech processing.
• To examine the developmental trajectory of using visual speech cues for lexical access.

Main Methods:

• Participants (children N=129, adults N=29) were presented with familiar words in audio-visual, audio-only, or visual-only modalities.
• Following auditory-visual or auditory-only presentation, participants viewed target and distractor images.
• Target image looking time was measured to assess word recognition accuracy across speech modalities.

Main Results:

• Adults demonstrated high accuracy, with a slight decrease in visual-only recognition.
• Children's looking times were above chance for audio-visual and audio-only conditions.
• Visual-only word recognition was not above chance until age six, with earlier development for /k/-initial words.

Conclusions:

• Flexible use of visual speech cues for lexical access develops gradually throughout childhood.
• Explicit behavioral measures reveal a later emergence of visual speech processing compared to implicit tasks.
• Auditory speech processing is robust in children, while visual speech integration develops over time.