Eye-tracking is useful in behavioural first language acquisition studies, since it makes it possible to interpret responses of pre-verbal infants. Although data obtained from a high-resolution eye-tracking system offers a range of possible analyses, total looking time towards different areas of the screen is still the most commonly used measurement in infant studies. The present study investigates the possibilities of event-related gaze analysis in an attempt to better make use of the advancing technology. Infants’ ability to match intensity across modalities was tested using both traditional visual preference analysis and event-related gaze analysis. Total looking time towards target (visual size and auditory intensity match) versus non-target was measured, and it was established that infants (n=58, 7.3 months, range 4 to 10 months) look significantly longer to target. The visual stimuli were then organized horizontally on the screen according to size, and auditory stimuli with different intensity levels were presented to the infants. The average horizontal gaze shift (normalized for initial position on the screen) at auditory stimuli onset was plotted over time. As predicted, infants (n=25, mean age 7.9 months, range 7 to 9 months) shift their gaze towards the visual stimuli matching the auditory stimuli in magnitude, although the results are only significant during very short intervals after stimuli onset. In conclusion, the event-related gaze analysis method seems promising since the results are in line with those from the traditional preferential looking paradigm in the present study, suggesting that further fine-tuning of the analysis method is worth pursuing.
2011. 259-260 p.
Abstract published in Book of Abstracts of the 12th Congress of the International Association of the Study of Child Language.