Abstract

This study was conducted to investigate the cognitive-neuropsychological characteristics of the learning disorder(LD) subtypes. We defined three LD subtypes by their clinical manifestations, our criteria for diagnosis, and deficient performances on the parts of KEDI-WISC and the Basic Achievement Test. As the result, we found the Verbal type(VLD), Nonverbal type(NVLD) and attention problem combined type (LD+ADD), and then compared their neuropsychological, intelligence, and academic achievement test data. The results supported the view that LD subtypes are related to specific assets and deficits in neuropsychological functions. The VLD type and LD+ADD type revealed primary problems in reading and spelling, and in the phonological coding of written language. The NVLD types had specific problems in hand-writing and spatial cognition. They showed deficits in visual-spatial-perceptual organization, complex tactile perception, complex motor skills, and social cognition. The LD+ADD type showed attention deficits and more severe reading and spelling errors than VLD type. Discriminant analysis indicated that overall percentage of correct classification was 60%. TPT and Spelling test scores were highly correlated with Function 1 which discriminate NVLD type from other types. And CPT and Purdue Pegboard scores were very effective discriminants for the LD+ADD type. For successful classification of LD subtypes and clinical implication, convergent and discriminant validity of a particular subtype and limitation of present study were discussed.