A Behavioral Comparison of Male and Female Adults with High Functioning Autism Spectrum Conditions

Abstract

Autism spectrum conditions (ASC) affect more males than females in the general population. However, within ASC it is unclear if there are phenotypic sex differences. Testing for similarities and differences between the sexes is important not only for clinical assessment but also has implications for theories of typical sex differences and of autism. Using cognitive and behavioral measures, we investigated similarities and differences between the sexes in age- and IQ-matched adults with ASC (high-functioning autism or Asperger syndrome). Of the 83 (45 males and 38 females) participants, 62 (33 males and 29 females) met Autism Diagnostic Interview-Revised (ADI-R) cut-off criteria for autism in childhood and were included in all subsequent analyses. The severity of childhood core autism symptoms did not differ between the sexes. Males and females also did not differ in self-reported empathy, systemizing, anxiety, depression, and obsessive-compulsive traits/symptoms or mentalizing performance. However, adult females with ASC showed more lifetime sensory symptoms (p = 0.036), fewer current socio-communication difficulties (p = 0.001), and more self-reported autistic traits (p = 0.012) than males. In addition, females with ASC who also had developmental language delay had lower current performance IQ than those without developmental language delay (p<0.001), a pattern not seen in males. The absence of typical sex differences in empathizing-systemizing profiles within the autism spectrum confirms a prediction from the extreme male brain theory. Behavioral sex differences within ASC may also reflect different developmental mechanisms between males and females with ASC. We discuss the importance of the superficially better socio-communication ability in adult females with ASC in terms of why females with ASC may more often go under-recognized, and receive their diagnosis later, than males.

Approximating Implicit and Explicit Mentalizing with Two Naturalistic Video-Based Tasks in Typical Development and Autism Spectrum Disorder

“…Exploratory analyses of gender differences in the autistic sample yielded significantly higher performance on both direct and indirect tasks of male ASD participants compared to females. Recently, a growing number of studies have reported gender differences within ASD on various behavioral measures including cognitive abilities (Boelte et al 2011;Lai et al 2011;Lord et al 1982) and social cognition in particular (Carter et al 2007;Golan et al , 2007Sucksmith et al 2013). In contrast to our results, previous studies have found higher facial emotion recognition performance in adult females with ASD compared to males Sucksmith et al 2013).…”

Autistic characteristics in adults with epilepsy

“…[EQ] in ASD females (Lai et al, 2011). This recent study found no female or male difference in systemizing ability employing self-reported rather than empirical measures (ibid.).…”

“…However some studies have demonstrated that females with AS perform worse on FER than matched controls such as Golan and colleagues, although these results are based on comparisons between 6 females with ASD and 5 age and IQ matched controls (Golan et al, 2006). However, in support of an affective deficit in females with ASD, a recent study of 33 males and 29 females found that males and females do not differ on selfreported empathy measured employing the Empathy Quotient [EQ] as a broader measure of basic emotional ability (Lai et al, 2011). This supports an early study employing the EQ of 65 males and 25 females with AS or HFA which suggests a more general impairment in identifying complex emotions .…”

“…Little research has compared males to females with ASD, however a recent study by Lai and colleagues found that females presented more sensory but less socio-communication symptoms, and scored higher for autistic traits in adulthood than males (Lai et al, 2011). Overall, such studies are lacking.…”

“…Consistent with this theory, Temporal lobe epilepsy [TLE] has been associated with impairments in temporal and frontal lobes, and more recently in the pre-frontal cortex. Research suggests that those with TLE have lower connectivity to brain regions outside the temporal lobe structures, such as the medial prefrontal cortex and other extratemporal regions, where no abnormal EEG activity is detected (Laufs et al, 2007).…”