19012
Eye-Tracking Differences in Social Stimuli in Patients with Rett Syndrome and Autism Spectrum Disorders
Although Rett syndrome (RETT) was considered a manifestation of Autism Spectrum Disorders (ASD), many aspects peculiar to each of these conditions make them very different and deserve to be even more clarified, so that diagnosis and therapeutic and educational interventions can be as effective as possible for one and other condition.
Objectives:
In this study, we used eye tracking technology to compare the visual fixation in social stimuli in patients with RETT and ASD.
Methods:
Visual fixation at social stimuli was analyzed in 14 Rett syndrome (RETT) female patients (age range 4-30 years), 11 Autism Spectrum Disorders (ASD) male patients (age range 4-20 years), and 17 children with typical development (TD). Patients were exposed to three different pictures (two of human faces and one with social and non-social stimuli) presented for 8 seconds each on the screen of a computer attached to an eye-tracker equipment.
Results:
Percentage of visual fixation at social stimuli was significantly higher in the RETT group compared to ASD and even to TD groups. Older RETT patients looked shorter time at social stimuli (human faces) and longer time at non-social stimuli (clock). Also, positive correlations were significant in TD group regarding all three social stimuli, without any correlation regarding non-social stimuli (clock); that is, older typically developing children looked at target areas longer than younger ones.
Conclusions:
Visual fixation at social stimuli seems to be one more endophenotype making RETT to be very different from the ASD. Now we can add to such objective and systematic findings that patients with RETT are undoubtedly more socially engaged than those with ASD and even than younger TD children, although such social engagement tends to decrease with age in RETT and to increase in young TD children. RETT patients present social domain more preserved than other cognitive aspects, at least regarding what we know up to now, indicating probably more functional areas which may be focused on in the development of new therapeutic and leisure strategies. It is a fact that eye tracking technologies have made possible to understand ever better not only the cognitive pathways of patients without verbal communication and, in the case of RETT, without motor possibilities, but also the different outcomes involving RETT and ASD.