The degree of selectivity or guidance underlying search was tested by
having subjects search for a target (a red vertical or green horizonta
l bar) among Similar (red horizontal and green vertical bars) and Diss
imilar distracters (blue and yellow diagonal bars). If search is indee
d a guided process, then the Dissimilar items should not be given the
same scrutiny as elements sharing a feature with the target. The frequ
ency of eye movements directed to the two distracter types was used as
an indicator of this scrutiny. The analysis revealed almost equal per
centages of saccades to Similar and Dissimilar elements (55% and 45%,
respectively). Although indicating some evidence for selectivity durin
g oculomotor search, this finding suggests that simpler and less optim
al strategies may undermine the more efficient guided search algorithm
. Copyright (C) 1996 Elsevier Science Ltd.