FACILITATION OF SACCADES TOWARD A COVERTLY ATTENDED LOCATION IN EARLY INFANCY

Covert shifts of visual attention may be demonstrated in both adult and infant subjects by facilitation of reaction times to make a saccade to a previously cued location. However, this facilitation may be interpreted in terms of a direct effect on the eye movement system. In the present experiment, we attempted to train 4-month-old infants to make a saccade in the location opposite from that in which a cue appeared. Following such training, we examined the reaction time to occasional probe targets that appeared in the same location as the cue. Infants were faster to respond to a target in this location than they were to respond to it either in the training (expected) location or in baseline trials. We interpret the results as providing further evidence for covert shifts of attention in 4-month-old infants, and suggest that the effects of covert shifts of attention on the eye movement system are independent of those from sequence learning.