excerpt from: The Syndrome of Nonverbal Learning Disabilities:
Clinical Description and Applied Aspects 

Michael A. Roman
The University of Texas 

...Some clinicians have also suggested that Asperger's syndrome and NVLD are similar disorders. This is a controversial assertion. Many researchers have questioned the validity of Asperger's syndrome as a distinct diagnostic entity apart from autism (Semrud-Clikeman & Hynd, 1990; Wing, 1991). In essence, the lower functioning children diagnosed with Asperger's may be more properly diagnosed as autistic. In turn, many of the higher functioning children diagnosed with Asperger's syndrome may instead be children with NVLD who have been misdiagnosed. ... (Read entire article)