Abstract
Our visual attention shifts without eye movements, called covert attention. Covert attention is widely known to influence the visual perception in adults (e.g. Carrasco & Barbot, 2014). However, the development of covert attention has been still unclear. To study early developmental stage of covert attention in infants, the present study used a spatial cueing task. In this task, 3- to 4- month-old infants learned to discriminate a spatially cued target, an oriented grating patch (either horizontal or vertical) in Experiment 1 or a drifting grating patch (upward/downward) in Experiment 2. During the learning phase, a circle cue appeared on the right or left of the display for 100 ms, which was immediately followed by a target for 200 ms at the cued location. A non-target object (a tilted line in the opposite orientation, Experiment 1 or an opposite motion direction, Experiment 2) was presented simultaneously at the opposite location. Infants did not shift her/his gaze to the cue and the target within this duration because the saccade latency in infants aged around 4 months is above 400 ms, indicating that the cueing effect, if any, can be attributed to infants’ covert attention. After this learning phase, the target and non-target were presented side by side during the test phase. If infants’ covert attention was directed to the spatially cued location, infants would learn the cued target and they would show a novelty preference to the non-target. As expected, infants looked at the non-target longer than the target in both Experiments during the test phase. We conclude that infants’ visual attention was covertly driven by the exogenous cue, and they could discriminate the cued stimuli without their eye movements.