Is Theory of Mind Understanding Impaired in Males with Fragile X Syndrome?

Abstract

Males with fragile X syndrome (FXS) have difficulties with social interaction and many show autistic features. This study examines whether the social deficits characteristic of FXS stem from difficulties with theory of mind. Two groups of boys with FXS participated: a group with few autistic features and a group with many autistic features. An intellectual disability control group also participated. In addition to using standard theory of mind tasks, new techniques were used that were able to separate out the various processing demands of the task (e.g., memory, inhibitory control). Overall, the findings indicate that both groups of boys with FXS have difficulty with theory of mind tasks compared to an intellectual disability control group. However, both groups with FXS also performed worse on control trials. Theory of mind difficulties are likely to be an important aspect of the FXS clinical profile, however these difficulties may stem from general information processing deficits.

A Comparison of Pragmatic Language in Boys With Autism and Fragile X Syndrome

“…Individuals with ASD are known to struggle with abstract social concepts such as humor (Ozonoff & Miller, 1996) and the inability to appreciate jokes is thought to stem from impaired social understanding, which is core to ASD (Baron-Cohen, 1988; Siegal, Carrington, & Radel, 1996; Yirmiya, Erel, Shaked, & Solomonica-Levi, 1998). Social-cognitive impairments have also been documented among individuals with FXS (Grant, Apperly, & Oliver, 2007; Lewis et al, 2006; Losh, Martin, et al, 2012), and therefore similar performance in skills that rely on social understanding, such as humor signaling, might be expected in individuals with ASD-O as well as FXS-ASD. Given that shyness and anxiety are characteristic of FXS (Hagerman, 2002), perhaps the boys with FXS-ASD were less likely than those with ASD-O to become comfortable enough to joke with the examiner, resulting in less opportunities to exhibit inappropriate humor (participants who did not attempt to make any humorous remarks were not coded on this item by default).…”

Nonspecificity and theory of mind: New evidence from a nonverbal false-sign task and children with autism spectrum disorders

“…1 The youngest mean age that Apperly et al's (2004) FB task has been established is 13 years 3 months with a mean verbal mental age of 6 years 10 months in a sample of atypically developing children (including children with fragile X syndrome and intellectual disability; Grant, Apperly, & Oliver, 2007). Thus, children aged below 7 years and over 3 years were recruited.…”

The Assessment and Presentation of Autism Spectrum Disorder and Associated Characteristics in Individuals with Severe Intellectual Disability and Genetic Syndromes

“…According to some studies, the rate of autism and social avoidance behaviors increases with age in males with full mutation FXS (Hatton et al, 2006;Roberts et al 2007), while improvements in core symptomatology with age are typically identified in individuals with idiopathic ASD (Charman et al, 2005;Moss, Magiati, Charman & Howlin., 2008) A similar pattern of findings has emerged with regard to the identification of socio-cognitive characteristics including Theory of Mind (ToM). Although initial studies of individuals with FXS and ASD described deficits in ToM (Cornish et al, 2008) subsequent research has showed that a general information processing and working memory deficit may account for this poor performance in this area rather than a specific ToM deficit (Grant, Apperly & Oliver, 2007). These findings suggest that the subtle differences between ASD and FXS at the level of behavior may also be reflected at the level of social-cognition.…”