Ouch and Yucks: Anxiety, Alexithymia and Empathetic Reactions in Autism

Background: The circumstances under which empathy is altered in Autism Spectrum Disorder (ASD) remain unclear, as previous studies did not systematically find differences in brain activation between people with and without ASD in empathy-eliciting paradigms. In addition, these studies did not always monitor whether the differences between ASD and controls were primarily due to ASD "per se", or to conditions overlapping with ASD, such as alexithymia and anxiety.

Objectives: The present study aimed at (1) clarifying the difference of activations in the empathy network between people with and without ASD viewing a particular kind of empathy eliciting stimulus, and (2) investigating the influence of alexithymia and anxiety on those activation differences.

Methods: Functional Magnetic Resonance Imaging (fMRI) data were collected from 47 participants (22 with ASD) viewing pictures depicting the hands and feet of unknown others in painful, disgusting, or neutral situations. We focused our analysis on two contrasts: painful vs. neutral and disgusting vs. neutral. For those contrasts, we extracted whole brain (WB) activity and activity in Regions Of Interests (ROIs) of the empathy network (frontal pole, supplementary motor area, thalamus, anterior cingulate cortex, posterior cingulate cortex, anterior insula, post central gyrus, and parietal operculum). We also explored the influence of alexithymia and anxiety on WB and ROI activity for those two contrasts, using regression and correlation analyses.

Results: We found that participants with ASD had decreased activation for both contrasts compared with control participants. However, these differences disappeared when either alexithymia or anxiety (both more elevated in the ASD group than in the control group) were controlled for. For ROIs, alexithymia (but not anxiety or autistic traits) was correlated with activation in the frontal pole for painful stimuli (after correction for multiple comparison).

Conclusions: Our results suggest that empathy is affected in ASD but that this association is complex and not necessarily attributable to ASD "per se".