Developmental right-hemisphere syndrome: clinical spectrum of the nonverbal learning disability.

We report the clinical characteristics of the developmental right-hemisphere syndrome (DRHS), a nonverbal learning disability, in 20 children (9 girls and 11 boys; mean age = 9.5 years) who also manifested attention-deficit/hyperactivity disorder (ADHD), severe graphomotor problems, and marked slowness of performance. Diagnostic criteria for this study included (a) emotional and interpersonal difficulties; (b) paralinguistic communication problems; (c) impaired visuospatial skills, verbal IQ > performance IQ, and verbal IQ > or = 85; and either (d) dyscalculia or (e) neurological signs on the left side of the body. In this group, verbal IQ was significantly higher than performance IQ (106.6 +/- 13.0 vs. 85.1 +/- 13.1, respectively, p < .01). Arithmetic was the lowest score among the verbal subtests (7.8 +/- 3.5, p < .01) and Geometrical Design was the lowest score among the performance subtests (5.8 +/- 1.7). Thirteen children had soft neurological signs on the left side of the body. ADHD was seen in all 20 children, marked slowness of performance in 16, and severe graphomotor problems in 18. The latter two features have not been previously described as part of DRHS.