Visual pop-out in infants: Evidence for preattentive search in 3- and 4-month-olds.

The present experiment tested for preattentive visual search in 3- and 4-month-old infants using stimulus features described by Treisman and Souther (1985) as producing visual "pop-out" effects in adults. Infants were presented with two visual arrays to the left and right of midline. One array comprised homogeneous elements, while the other had a discrepant element embedded in it. On the basis of previous research, we expected infants to fixate the array containing the embedded discrepant element. The pattern of fixation indicated detection of the embedded discrepant element for both age groups, but only with stimuli shown to elicit visual pop out in adults. This asymmetry in detection is consistent with the presence of preattentive visual search in infants as young as 3 months.