Temporal factors and subnormality in visual pattern recognition: A test of stimulus tract theory.

Abstract

Selected hypotheses from Ellis'' trace theory were tested. Thirty-two educable retardates (R), 32 equal MA normals (MA), and 32 equal CA normals (CA) were required to identify visual patterns formed by lights illuminated successively at various temporal separations. As predicted, Groups R and MA demonstrated significantly fewer correct identifications than Group CA. Contrary to prediction, only Group MA decreased significantly more than Group CA over increasing interstimulus intervals. These results, and a marginally significantly (p < .06) greater decrement for Group MA compared to Group R, suggest that the theory be modified to include 2 independent trace processes: trace amplitude positively related to IQ and CA; trace duration positively related to CA only.