Asperger syndrome now comes under the single umbrella term of autism spectrum disorder (ASD). Since Asperger syndrome is no longer diagnosed but instead a diagnosis of ASD is given. It is classified as a neuro-developmental condition that affects how the brain processes information.New ASD classification · Symptoms of ASD · Diagnosis of ASD in adults. 1 Adults with serious mental health difficulties should already have been referred for diagnosis or other help. Autism spectrum disorders are described in both.