[Non-verbal learning disabilities]

In 1975, Myklebust proposed a special form of learning disabilities characterizes by impairment of spatial cognition, social interaction and conceptualization, and named it as non-verbal learning disabilities (NLD). Since the brain locus for spatial cognition was thought to be localized in the right hemisphere, NLD was regarded as a disorder of the right hemispheric function. The clinical characteristics of NLD are almost identical to those of Asperger syndrome (AS), which was introduced in English literature in 1981. Since Asperger syndrome is regarded as one of the autistic spectrum disorders, and autism was once regarded as the left hemispheric dysfunction, it has long been believed that NLD and AS are clinically different entities. However, their clinical similarities have raised a growing opinion that these two disorders are probably identical or at least closely related.