A forced-choice reaction-time (RT) task was used to examine voluntary visual orienting among children and adolescents with trisomy 21 Down syndrome and typically developing children matched at an MA of approximately 5.6 years, an age when the development of orienting abilities reaches optimal adult-like efficiency. Both groups displayed faster…

Three experiments with observers aged 6 to 21 years of age examined the integration of shape information over successive glances. Results indicated age-related improvements in the sequential integration of shape information, both when integration occurs through successive glimpses over space and when information is separated only in time. (HOD)

Experiment 1 suggested that age differences in line-drawing interpretation among subjects between 6 and 24 years reflected changes in short-term memory for features and changes in strategies used to integrate features over space and time. Experiment 2 suggested that older observers were more active in their attempts to interpret drawings and that…