Spatial orienting following dynamic cues in infancy: grasping hands versus inanimate objects.

Abstract

Movement perception facilitates spatial orienting of attention in infants (Farroni, Johnson, Brockbank, & Simion, 2000). In a series of 4 experiments, we investigated how orienting of attention in infancy is modulated by dynamic stimuli. Experiment 1 (N = 36) demonstrated that 5-month-olds as well as 7-month-olds orient to the direction of a dynamically grasping human hand. Experiment 2 (N = 36) showed that 7-month-olds orient covertly to direction of a geometrical shape moving on the trajectory of the grasping movement, but 5-month-olds do not. Experiment 3 (N = 18) showed that mere linear translating object movement does not elicit covert orienting of attention in 7-month-olds. In Experiment 4 (N = 18), we found that 7-month-olds process both grasping direction and movement direction, which resulted in increased reaction times when these cues conflicted. These findings suggest that orienting of attention reflects rapid detection of goal-directed agents. Five-month-olds need the information of both movement and grasping direction, whereas 7-month-olds can use each of these directional cues in isolation.