Compared to mental and chronological age-matched groups of normal children, six autistic children (1) did not maximize reinforcement; (2) sampled less, and less efficiently; and (3) were much less responsive to extinction. Autistic sampling behavior was redirected by stimulus change. Results are viewed as perhaps causally related to many…

Compares gifted preschool boys and girls with both a CA (Chronological Age)-matched group and an MA (Mental Age)-matched group on their performance on a spatial projective task, a cognitive perspective-taking task, and an affective perspective-taking task. The data seem to support the hypothesis that psychometric brightness implies cognitive…

Exploratory behavior of educationally mentally retarded 7- to 12-year-old children was compared to that of two independent groups of normal children matched on chronological and mental age. In a multidimensional assessment of exploration, results suggested that delays in exploratory behavior in retarded children are developmental in nature, and…

Four hundred subjects 8 to 11 years old were given a modification of the Weigl Color Form Sorting Test in an attempt to assess the influence of chronological age, mental age, intelligence, and vocabulary level on the ability to utilize various numbers and different kinds of criteria of classification. (Author/MP)

Forty children with mental retardation were compared on everyday leisure-time behaviors with children without mental retardation matched for mental age (MA) or chronological age (CA). Although MA best predicted overall functioning on leisure-time behavior, CA best predicted both single highest behavior performed and highest behavior considered too…

This study, involving 48 children and adolescents with Down's syndrome, found that chronological age and mean mental age collectively accounted for much of subjects' variability in vocabulary comprehension and syntax comprehension, with total passes on a hearing screening accounting for additional variability. (Author/DB)

Forty-nine children (ages 8-17) with mental retardation recognized facial expressions less accurately than did subjects without retardation who were matched on chronological age. Mental age-matched groups showed no differences in accuracy at a younger mental age, but a difference was found at an older mental age. (Author/JDD)