Children’s successful performance on the search task could also have relied upon language processes, which are known to be lateralized to the left hemisphere in most right-handed individuals. Internal use of language is a common mechanism by which individuals direct their own behavior, and Vygotsky (1986) has written extensively about this process in young children. Although 2-year-olds on average have a relatively limited vocabulary, it is entirely possible that they relied on internally-directed speech to guide their visual attention during the task. Interestingly, if this was in fact the case, then our results would suggest some overlap in these processes. Although this idea is speculative, it is supported by the fact that language and attentional control show a very similar developmental time course. Thus, to the extent that language processes are involved, goal-directed orienting may rely heavily on the maturation of left frontal brain regions.
