Determining Sex Differences in the Social Cognition of Adults with High-Functioning Autism Spectrum Disorder Using Advanced Mindreading Tasks

Background: At even three years of age, girls can understand another individual’s emotions and thoughts better than boys of the same age; that is, girls exhibit more advanced social cognition than boys in childhood (Baron-Cohen, 2003). Additionally, individuals with autism spectrum disorder (ASD) display inherent deficits in mindreading abilities. The results of the study, using the Cambridge Mindreading Face-Voice Battery, revealed that females recognized emotions from facial expressions better than males did, regardless of the diagnosis of Asperger syndrome (AS) (Golan et al, 2006). However, few studies have examined the role of sex differences in social cognition.

Objectives: We aimed to examine sex differences in the social cognition of adults with high functioning ASD using advanced mindreading tasks, as well as the relationship between mindreading abilities, the symptoms of ASD, and IQ.

Methods:  The 60 participants consisted of 41 male adults with ASD (mean age = 30.9±8.3 yrs, mean Full IQ (FIQ) =108.5±13.3, mean Verbal IQ(VIQ)=113.3±13.8) and 19 female adults with ASD (mean age =31.7±8.0 yrs, mean FIQ =105.7±11.0, mean VIQ=109.4±9.7). There was no significant difference in age, FIQ and VIQ scores between these two groups. The participants performed advanced mindreading tasks “The Motion Picture Mind-Reading Test”(Wakabayashi & Katsumata,2011) consisting of the evaluation of 41 video clips that were designed to assess mindreading ability. A word or a phrase that expressed a mental state was shown along with each video clip. The participants were asked to judge whether each word or phrase was appropriate for the paired scene. Autism Diagnostic Observation Schedule testing was also conducted with all participants to evaluate ASD symptoms.

Differences between the groups regarding accuracy rates for the advanced mindreading tasks were evaluated using an independent t-test. Additionally, we examined the correlation between the accuracy rates for the advanced mindreading tests and verbal IQ (VIQ), performance IQ (PIQ), FIQ, and ADOS scores.

Results: There was no significant difference in the accuracy rate for the advanced mindreading tasks between males (67.3±16.1) and females (69.7±2.7). The accuracy rate of advanced mindreading tasks and the ADOS social score showed a significant positive correlation in females (r=.648, p<.01), but not in males (r=.211, p=.185). Conversely, the correlation between the accuracy rate of advanced mindreading tasks and VIQ was significant for males (r=.323, p<.05) but not for females (r=.277, p=.251).  

Conclusions: These results suggest that male adults with ASD perform the mindreading tasks by using their intelligence, specifically that measured by VIQ. This result was the same as that in Happé’s study (1995) but that study did not consider sex differences. Our results also suggest that females with high functioning ASD may process the mindreading tasks through social cognition (ADOS social area). In the real world, males with high functioning ASD compensate for mindreading deficiencies by use of that portion of intelligence measured by the VIQ, whereas females perform the mindreading tasks through social cognition. The female’s strategy for mindreading may be the same as in individuals with typical development.