Differences In VISUAL FIELD Preference In EMOTION RECOGNITION BETWEEN CHILDREN with AUTISM Spectrum DISORDERS and Typical DEVELOPMENT

Background:  

Research has demonstrated that for the neurotypical population, reacting to and recognizing facial emotions improve when using the left visual field by employing the right brain hemisphere’s configural processes. Findings suggest that individuals with autistic spectrum disorders (ASD) seem to have intact neuronal circuitry for emotion recognition. However, they rely more on analytical “piecemeal encoding” mediated by the left hemisphere rather than recruiting the right hemisphere’s “perceptual Gestalt” processes. Thus, an ASD right visual field preference for emotion recognition has been suggested.

Objectives:  

The current study compared the effects of isolating visual fields on tasks of facial affect assessment performed by children with ASD and those with typical development (TD). ASD participants were expected to show a right visual field preference, while TD participants were predicted to demonstrate a left visual field preference as noted by fastest beats-per-minute finger pulse rate (BPM), shortest reaction time (RT) and highest percent accuracy (PA) when using the designated visual field to view facial stimuli. The study also explored the usefulness of a right visual field preference to predict overall autistic symptom levels in the context of executive functioning deficits.

Methods:  

Participants (N = 64) consisted of two equal-sized groups of children (5 – 19 yrs old) with ASD and TD matched by age and gender. Mixed design included two development groups (ASD,TD) and three within-group visual field conditions (both, BVF;  left, LVF; right, RVF). Participants wore eyewear with an opaque lens occluding one eye and the inner medial aspect of the other eye to isolate different visual fields. Facial affect stimuli depicting happy, sad and angry emotions were presented across BVF, LVF and RVF conditions.  BPM over each visual field block, RT for each trial and PA over each visual field block were measured. Executive function and autistic trait levels were quantified using a pediatric Executive Function Index (EFI) and the Autism Spectrum Quotient (AQ).

Results:  

ASD participants demonstrated significantly slower BPM, longer RT and lower PA in performing emotion attribution tasks when compared to TD controls. When using the RVF, ASD participants demonstrated significantly faster BPM compared to pulse rates when using LVF or BVF. Shorter RT and higher PA were observed when ASD participants used the RVF to assess facial emotions compared to response and accuracy rates when using the LVF. Pulse rates of TD participants trended toward a left visual field preference. Greater differences between LVF and RVF performance along with greater differences between BVF and RVF performance in BPM, RT and PA were found to be predictive of increased autistic trait level. Regression models explained half of the variance in autistic trait level when impairments in executive functioning were included.

Conclusions:  

These findings provide support of a right visual field preference in ASD facial affect processing. Right visual field preference may be a potential endophenotype, contributing to the social deficits seen within the spectrum. The usefulness of including left visual field practice in social skills therapy to improve facial affect comprehension in children with ASD is being explored.