ABSTRACT
There are rare instances of unusual memories displayed by retardates, but the interesting fact is that we do not yet know the limits of the ordinary retardate's capacity to process information with little or no error. A channel capacity cannot be derived from the published results, since interstimulus intervals and numerosity levels were variously collapsed in presenting the data. When temporal grouping was congruent with sensory modality, the retardate's capacity was raised. The inferior performance of retardates on the eight-digit couplet redundancy condition probably reflects the fact that even this reduced information load was still beyond the retardate's basic capacity. Educable adolescent retardates were administered an absolute judgment task in which they judged the scale position of a pointer set at different positions along a horizontal line. An informational analysis revealed that a center anchor raises the channel capacity of retardates from seven to eight.
