Andries Sanders' dissertation examined selective mechanisms in the functional visual field, and much of his work since has been concerned with the stages that underlie visual information processing particularly while making saccades. The authors argue that the study of orienting in the functional visual field is timely because it deals with the relation of covert attention shifts, eye movements and head movements to their underlying neurology. In this paper, the authors develop a method to study learning of sequences at all ages from infants to adults. Their studies focus on how learning influences anticipatory eye movements. The authors examined the learning of unambiguous and context dependent sequences by 4-, 10-, and 18-month-old infants and undergraduates. They found clear learning of unambiguous sequences at 4 months, but learning of context dependent associations was found only in 18-month-olds and in adults. The authors hypothesise that the learning of unambiguous sequences by 4-month-olds reflects maturation of a basal ganglia-parietal circuit related to adult implicit learning, while the learning of context dependent sequences requires development of frontal structures underlying more general attentional abilities. (A)
Samenvatting