The diagnosis of Asperger's Syndrome may sometimes be a misinterpretation of a personality type of ISTP or INTP, according to researcher Robert G. Chester in an article published in the Journal of Psychological Type. Many of the symptoms of Asperger's syndrome, including a preference for solitude, visual and intuitive thinking, and a critical and objective communication style, are similar to characteristics of normal type development among ISTPs and INTPs.

The author also notes that mothers who are ENFJs or ESFJs may find their ISTP and INTP children particularly difficult to understand, which may lead to the children being labeled with a diagnosis of Asperger's disorder. Although Chester found no evidence that Asperger's syndrome is not a valid diagnosis, the syndrome may in some cases be confused with the normal personality traits of INTP and ISTP types.