Strength of lateralisation for processing facial emotion in relation to autistic traits in individuals without autism

Abstract

A great number of studies have shown that non-clinical individuals rely predominantly on the right hemisphere to process facial emotion. Previous studies have shown that males suffering from Asperger's syndrome show a typical right hemisphere bias for processing facial emotion (happiness and sadness) but a reduced right hemisphere bias for processing facial identity. This study looks at the lateralisation of all six basic emotions using the chimeric faces test in 64 non-clinical participants (32 males, 32 females) and correlates it with their autistic traits measured using the Broad Autistic Phenotype Questionnaire. For males only, regression analyses showed a relationship between the aloof personality trait and lateralisation for fear, happiness, and surprise. Males with high autistic scores on the aloof personality subscale (showing a lack of interest in social interaction) were more strongly lateralised to the right hemisphere for processing fear, happiness, and surprise. For males there was no relationship with anger, disgust, sadness, or non-facial stimuli, and for females there were no significant relationships at all. The autistic traits of rigidity and pragmatic language were not significant predictors of emotion lateralisation. The over-reliance on the right hemisphere for processing facial emotion in males seems to support the idea that the autistic brain could be seen as hyper-masculinised, possibly due to prenatal testosterone exposure.

Case of Asperger's Syndrome and Lesion of the Right Amygdala: Deficits in Implicit and Explicit Fearful Face Recognition

“…This is in line with findings that basic emotion identification is intact, but more complex tasks produce recognition errors in ASD (Castelli, 2005). Interestingly, one study (Vladeanu et al, 2012) reported that the discrimination of fear was lateralized to the right hemisphere in patients with ASD, which in this case might have interfered with the damage of the right amygdala. Gainotti (2012) proposed that the right amygdala is primarily responsible for automatic emotion processing.…”

Paranoid males have reduced lateralisation for processing of negative emotions: An investigation using the chimeric faces test

“…It is therefore possible that the present findings may also be associated with social anxiety. A similar argument may be posed for other variables that have been found to be associated with paranoia and/or lateralisation, such as depression (e.g., Bourne & Vladeanu, in press;Kucharska-Pietura & David, 2003;Rabany, Weiser, Werbeloff, & Levkovitz, 2011) or theory of mind and autistic traits (e.g., Gooding & Pflum, 2011;Vladeanu, Monteith-Hodge, & Bourne, 2012). Indeed, it has been suggested that low self-esteem is a vulnerability factor for depression (Sowislo & Orth, 2012).…”

Other Biological Aspects of the Broad Autism Phenotype

“…Thus, the authors of this study hypothesized the existence of an interaction between ASD personality traits, emotion processing abilities, and the degree of brain hemisphere lateralization for processing emotions that are communicated through facial expressions. They noted that people with tendencies for social disinterest and rigidity may be likely to have stronger brain lateralization for emotion processing (Vladeanu et al, 2012).…”

“…The visual trials in the Vladeanu et al (2012) study included chimeric faces that displayed all of the basic emotions: anger, disgust, fear, happiness, sadness, and surprise. Analyses of results yielded no significant findings for female participants.…”