Complex visual discriminations in cultural familial retardates and normal children

Examined information processing in a visual matching task in a group of 12 cultural familial retardates (mean age = 18 yrs) and a group of 31 normal children in Grades 2, 5, or 8, using digit sequences of varying complexity as the stimuli. Reaction times (RTs) of normal adult Ss making same judgments do not fit into a single-process self-terminating feature testing model, while those for different judgments do. This study found that (a) the same-different relationship was the same for normal Ss and retardates, with same judgment RTs deviating from predictions of a self-terminating model; (b) overall RT was a function of Ss' mental age; and (c) differences in RTs between groups were due primarily to "intercept" rather than "slope" effects, although evidence of a possible slope difference was found between the 8th graders and the other groups. (PsycINFO Database Record (c) 2006 APA, all rights reserved).