A Comparison of the Performance of Normal,Learning Disabled,and Educable Mentally Retarded Children on Cattell's Ability Constructs

Abstract

The purpose of this investigation was to explore the use of Cattell's ability traits (fluid and crystallized intelligence, visualization, and fluency) as difference characteristics of the learning disabilities category. Previous research and conceptual differences among the learning disabled, normal, and educable mentally retarded populations suggested that learning disabled children would perform better than educable mentally retarded children but not as well as normal children on measures of the traits. Fifteen subjects between the ages of 7 years and 8 years 6 months from each category were administered measures of the traits. An analysis of the scores indicated significant differences between learning disabled and normal children and between learning disabled and educable mentally retarded children on the visualization and fluency measures. Significant differences between the groups were also found on the crystallized intelligence measure but not in fluid intelligence. The results suggest that the crystallized intelligence, visualization, and fluency traits may represent difference characteristics of the learning disabled category, while fluid intelligence may not.