Self-Related Representation in Individuals with High-Functioning Autism

Background: Autism spectrum disorder is a developmental disorder which is characterized by the lack of social interaction with others, including natural communication and eye contact (DSM-IV-TR, American Psychiatric Association, 2000).  Individuals with autism lack self-awareness (Lombardo et al., 2009; Toichi et al., 2002) and have difficulty empathizing with others (Baron-Cohen, 1995; Lombardo et al., 2007).  Although these deficits were observed by previous studies, most of the target stimuli were constructed for neurotypical individuals.  It is still unclear how individuals with autism understand other people with autism.

Objectives: We investigated whether individuals with autism show self-awareness and empathize with protagonists of sentences who have autistic traits using fMRI.  We hypothesized that ventromedial prefrontal cortex (vmPFC), known to be sensitive to self-relevant information processing (Lombardo et al., 2009), should be activated when judging someone similar to themselves.

Methods: 15 (2 females) high-functioning individuals with autism spectrum disorder and 15 (2 females) neurotypical control participants participated in the experiment.  Age and IQs were matched between the groups.  During the fMRI scan, participants read sentences and made judgments about them by using 2 buttons (Yes or No).  Each sentence described the protagonist’s behavior as autistic or non-autistic.  For Self judgments with an autistic protagonist, they read a sentence (e.g., I would rather be alone than with others) and made a judgment (Do you agree with the sentence?).  For Other judgments with a non-autistic protagonist, they read a sentence (e.g., Yuya would rather be with others than alone) and made a judgment (Do you think you are similar to him?).  Gender was matched between the participant and the protagonist.

Results: In the behavioral results, the interaction between group and protagonist was significant (F (1, 28) = 27.20, p < .05, MSe = 6.28, Prep = .99, ηp2= .49).  Post hoc analysis showed that while the autism group rated Yes responses for autistic protagonists more than the control group (F (1, 28) = 16.26, p < .05, MSe = 4.55, Prep = .99, ηp2= .37), the control group rated Yes responses for non-autistic protagonists more than the autistic participants (F (1, 28) = 35.52, p < .05, MSe = 2.75, Prep = .99, ηp2= .56).  Thus, both groups found matched protagonists similar to themselves.  In the fMRI study, during Self and Other judgments, vmPFC was activated in both groups: when the autistic group judged protagonists with autistic behavior, and the control group judged protagonists without autistic behavior.  Moreover, in the Other judgment, precuneus was activated when the autistic group judged protagonists with autistic behavior and the control group judged protagonists without autistic behavior.

Conclusions: These findings suggest that individuals with autism spectrum disorder show self-awareness toward other individuals similar to themselves as well as neurotypical individuals do.  Individuals with autism are likely to empathize with other people with autism.  As these findings explain the characteristics of individuals with autism, they may also contribute to improving special needs education, educational intervention, and developmental support for individuals with autism.