Does Baseline Rsa Play a Role in Social Skills and Sensory Sensitivity in Adults with Autism Spectrum Disorders?

Background:

There is increasing scientific attention for the possible relationship between autonomic functioning and ASD symptoms. The evidence is rather mixed. Some find no differences between people with and without ASD in autonomic functioning during sensory or social stimulation, whilst others find atypical reactions in people with ASD (see review of Klusek et al., 2015). The major focus, so far, was on autonomic responses. However, some suggest that baseline levels of autonomic functioning might be more important (e.g., Porges et al., 2013).

Objectives:

We examined whether baseline respiratory sinus arrhythmia (RSA) is related to social skills and sensory sensitivities in adults with and without ASD.

Methods:

38 ASD and 39 typically developing (TD) males (aged 18-45, mean=31.4; IQ>70, mean=104.5) were included. Baseline RSA was measured with an electrocardiogram and the VSRRP98 of the local university. Social skills were measured with a Dutch self-report social skills questionnaire (‘Inventory of Interpersonal Situations’). Sensory sensitivities were measured with the Adolescent/Adult Sensory Profile. For the current analyses a sensory sensitivity total score was calculated. We performed two multiple regression analyses with, respectively, sensory sensitivity and social skills as dependent variables. In both analyses, the predictors were baseline RSA and Group (ASD vs. TD) in step one and an interaction (Group*Baseline RSA) in step two.

Preliminary Results:

The groups did not differ in age or IQ. Regarding sensory sensitivity, the preliminary results showed that in step one the model explained 35.4% of the variance. After adding the interaction, the model explained a similar amount of variance (R² change=.00) and did not result in significant additional explained variance. Only group was a significant predictor (ASD>TD; β=-29.80, p=.00). Regarding social skills, similar findings were observed as the model explained 37.4% of the variance in step one and adding the interaction did not result in a significant increase in explained variance (R² change=.001). Again, only group was a significant predictor (ASD<TD; β=21.72, p=.00).

Conclusions:

These preliminary findings suggest that baseline RSA is not related to social skills and sensory sensitivity in adults with or without ASD, over and above group. Group is a relevant factor, which was to be expected as altered social skills and sensory sensitivities are at the core of ASD. Future research needs to determine whether an altered physiological ability to adapt to the environment is a better candidate to elucidate the potential relationship between autonomic functioning and ASD symptoms.