Trajectory assessments of cognitive, visuospatial, and academic profile in nonverbal learning disability (visuospatial developmental disorder).

Substantial progress has been made in defining children with nonverbal learning disability (NLD), but longitudinal studies are still lacking. To start filling this gap, we examined changes in general cognitive functioning, visuo-constructive skills, and academic profiles in a group of children with NLD, also taking into account any internalizing and externalizing symptom as transdiagnostic features. A total of 30 participants (24 boys) diagnosed with NLD were tested twice, with a three-year gap between the two assessments (T1: at age 8-13; T2: at 11-16), on their cognitive profile, visuospatial abilities, and academic performance (i.e., reading, writing and arithmetic abilities). At T2, any internalizing and externalizing symptom was also investigated. Statistically significant differences emerged between the two assessments in terms of the WISC-IV Perceptual Reasoning Index (PRI), handwriting speed and arithmetical fact retrieval. The NLD profile seems to be characterized by a relative stability in its core features during a child's development, as regards both weaknesses (i.e., visuospatial processing) and strengths (i.e., verbal abilities). The presence of internalizing and externalizing symptoms also suggested the importance to analyze transdiagnostic features rather than only sharp boundaries between conditions.