Eye movement evidence for an immediate Ganong effect

Area of Science:

• Psycholinguistics
• Cognitive Science
• Speech Perception

Background:

• Listeners often interpret ambiguous speech sounds to form words within their context.
• This phenomenon may involve lexical feedback or a dedicated phonemic decision system.
• Lexical feedback theories predict a delayed and strengthening influence of word knowledge on sound perception.

Purpose of the Study:

• To investigate the temporal dynamics of lexical influence on phonemic categorization.
• To test the prediction of delayed and increasing lexical feedback.
• To introduce a novel eye-tracking analysis method for visual-world tasks.

Main Methods:

• Two experiments utilized eye-tracking to monitor listeners' categorization of ambiguous speech sounds.
• Listeners identified phonemes with visually presented response options.
• Gating experiments confirmed the precise timing of lexically relevant information in the speech signal.

Main Results:

• Lexically relevant information immediately guided eye movements towards the contextually supported word.
• This effect on eye movements diminished over the trial duration, rather than increasing.
• The observed pattern challenges the delayed lexical feedback account of speech perception.

Conclusions:

• The lexicon's influence on phonemic decisions appears to be immediate rather than delayed.
• Findings contradict models predicting a gradual increase in lexical feedback strength.
• The study introduces a new analytical approach for visual-world eye-tracking data in psycholinguistic research.