Recent studies using the Visual Expectation Paradigm (VExP) have examined young infants eye movements to predictable visual events as a measure of cognitive performance. The purpose of this proposal is to examine the velocity and amplitude of anticipatory and reactive saccades made by young infants during the VExP task: (1) to quantify and describe the amplitude and velocity of anticipatory and reactive saccades to dynamic, predictable, targets, (2) to use these properties to establish a standard time criterion for reactive saccades based on infant data, (3) to investigate whether the saccadic system matures at the same rate for male and female infants, and (4) to determine if the characteristics of correct and incorrect anticipatory saccades differ. It is hypothesized that 3-month old infants at least 166 ms (possibly 200 ms) of processing time of reactive saccades. Infants eye movements will be recorded with a 60Hz TV system. A computerized eye tracker system will collect the data from the video record and determine the spatial position and timing of each critical saccade to the visual targets. This study will provide new information on the development and characteristics of goal-directed anticipatory and reactive saccades in infancy, where these voluntary eye movements develop at equivalent rates for males and females, and may contribute another measurement tool (correct versus incorrect anticipatory saccades) for assessing cognition in infancy.
