Abstract
Introduction: The ability to discriminate between different phonemes is a crucial part of language development in the first year of life. At the same time that research has shown that language acquisition is a sensitive process that shows narrowing of which phonemes are discriminated in infancy, the paradigms that have been used to study this process have a number of shortcomings. These include temporal resolution, lack of a discriminatory response, and ambiguity of results. To overcome these shortcomings, the present study examined 6-month-old infants’ ability to discriminate between two different phonemes by means of an eye-tracking task, the Visual Expectation Cueing Paradigm (VExCP). Method: In the VExCP, one randomly presented phoneme (paired with a central visual stimulus) predicted a visual target on the right side of a monitor screen and the other randomly presented phoneme predicted a visual target on the left side of the screen or vice versa. The discriminatory phonemes used in the current study were /ma/ and /na/ and infants were exposed to 30 trials of each randomly presented phoneme. If the infants could discriminate between the phonemes, then they would correctly make anticipatory eye movements to the target location at a rate greater than chance. Results: Findings indicated that 6-month-old infants successfully discriminated between the two different phonemes forming an expectation for the phoneme-target location relations and thereby making correct anticipatory eye-movements to the correct target location at a rate greater than chance. Conclusion: The results indicate that the VExCP and eye movements represent a valid paradigm by which to study phonemic discrimination and its development in infancy while overcoming the weaknesses of previously used paradigms.