Many people see that SPD and AS are a similar, or even the same disorder, see (various quotes, #1 is from Wing herself):
Quote:
Schizoid personality
The lack of empathy, single-mindedness, odd communication, social isolation and over-sensitivity of people with Asperger syndrome are features that are also included in the definitions of schizoid personality (see review by Wolff & Chick, 1980). Kretschmer (1925) outlined some case histories of so-called schizoid adults, one or two of which were strongly reminiscent of this condition, although he did not provide sufficient detail to ensure the diagnosis. For example, one young man had no friends at school, was odd and awkward in social interaction, always had difficulty with speech, never took part in rough games, was oversensitive, and very unhappy when away from home. He thought out fantastic technical inventions and, together with his sister, invented a detailed imaginary world.
There is no question that Asperger syndrome can be regarded as a form of schizoid personality. The question is whether this grouping is of any value. This will be discussed below in the section on classification.
Quote:
Schizoid personality in childhood (DSM-IV)
Schizoid personality in childhood is defined by solitariness, lack of empathy, emotional detachment, increased sensitivity, at times paranoid ideation, and single-minded pursuit of special interests. All these features are seen in Asperger syndrome, and comorbid issues (depression or behaviour problems in particular) are likewise similar for both conditions. On the basis of evidence presented in Wolff's (1998) discussion of schizoid personality in childhood, we have concluded that there is significant overlap between schizoid personality in childhood and Asperger syndrome.