The construct and predictive validity of adaptive behavior was investigated using a multitrait multimethod analysis with 66 mentally retarded institutionalized persons. Adaptive behavior had high convergent validity and low discriminant validity and predicted MA program placement better than did MA, suggesting that adaptive behavior scores could…

Despite Spitz's (1982) contention that his conclusions are necessarily in conflict with those arising from factor analysis, this article demonstrates how results from factor analysis can provide insights into data he cites. (Author/MP)

Reprints from: Gene V. Glass, Laboratory of Educational Research, University of Colorado, Boulder, Colorado 80302.

Reprints from: Arthur R. Jensen, School of Education, University of California, Berkeley, California 94720.

Studies comparing the strengths and weaknesses of intellectually retarded and superior groups are reviewed, with particular attention given to studies in which these extreme groups were matched with each other on mental age. (Author)

Discusses the respective roles of rate of learning and level of cognitive development in determining intellectual performance in 156 normal and retarded children matched for mental age. (Author/LLK)

Thirty young children with handicaps were assessed on five self-recognition mirror tasks. The set of tasks formed a reproducible scale, indicating that these tasks are an appropriate measure of self-recognition in this population. Data analysis suggested that stage of self-recognition is positively and significantly related to cognitive…

The paper examines the meaning of transitional objects and attachment to significant others in 18 severely retarded children (mean age 5.2 years). Five case studies illustrate that the use of objects and attachments can be seen as a normal phenomenon and that often the children are responding appropriately to emotional events with behaviors near…

Sensitivity to logical contradiction, as manifested by surprise reaction to the Jastrow illusion, was investigated in 30 nonretarded children, 30 educable mentally retarded (EMR) children equated for chronological age, and 30 EMR children equated for mental age. (Author)

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…

Persons representing the extremes of intelligence cannot be included in the same study unless they are approximately equated on mental age, in which case the relative performances of the extreme groups can provide useful information about the nature of intelligence. (Author/RD)

The paper notes A. Hore and W. Tryon's support of the developmental position that persons with and without mental retardation of similar mental age show similar cognitive patterns, but suggests that mental age is psychometrically invalid and Piagetian tasks are inappropriate to evaluate this position. An information processing approach is…

Findings of three studies indicate that young children with Down syndrome perform similarly to typical controls matched on mental ages (MAs) of approximately 3 years. However, by developmental age of 4 years, children with Down syndrome performed worse than both MA-matched typical children and children with non-Down syndrome types of mental…