Supporting data for PhD thesis "Pain Expression Shapes the Neural Mechanisms of Empathy in Autistic and Neurotypical Adults: Evidence from EEG and fNIRS"
<p dir="ltr">Pain empathy, an ability to feel and understand others’ distress. Most pain empathy research has relied on using static and unnatural images of either body limbs or facial expressions, which failed to capture the dynamic nature of pain in real-life scenarios. While empathy is known to be altered in autistic adults, the underlying neural mechanisms are underexamined. To address these gaps, this dissertation has developed a kinetic pain empathy paradigm that featured animated videos with unfolding pain events followed by body gestures and facial expressions. Furthermore, by manipulating the congruence between these two pain expressions and involving both autistic and neurotypical adults, we examined the influence of the pain congruence on the neural mechanisms of empathy and to identify altered neural patterns in autistic adults.</p><p dir="ltr">Study 1 (Chapter 2) used EEG data with 52 neurotypical adults. Multivariate pattern analysis revealed two-stage temporal dynamics of empathy. The findings highlight the crucial role of facial expressions in eliciting emotional arousal, while a later stage of cognitive reappraisal is highly involved in integrating different pain expressions. </p><p dir="ltr">Study 2 (Chapter 3) utilized fNIRS with 40 neurotypical adults to examine the influence of the congruence on the spatial neural mechanisms of empathy. Two-level linear mixed models showed that brain regions associated with facial expression perception, empathy, and conflict resolution were significantly modulated by pain and congruence. These results suggest that individuals generate and adjust predictions as pain unfolds, showing greater empathy for genuine pain expressed through body gestures, which was more significant when body gestures were paired with congruent facial expressions. However, incongruent facial expressions with pain led to the most unpredictable errors, requiring greater cognitive effort.</p><p dir="ltr">Study 3 (Chapter 4) compared EEG signals between 51 autistic adults and 58 neurotypical adults using the same paradigm as study 2. We found the comparable neural structure for empathy and conflict resolution between the two groups, but with different activation degrees. Autistic adults exhibited heightened emotional arousal to others’ pain and increased alertness to incongruent pairings in the early stage. In the late stage, autistic adults expended more cognitive resources for reappraisal, suggesting a specific weakness in the top-down cognitive reappraisal of social contexts in autistic adults. </p><p dir="ltr">In sum, this dissertation used multimodal techniques, advanced analytical approach, and self-developed experimental paradigms to examine the neural mechanisms of pain empathy. These findings highlight the influence of dynamic pain expressions and their congruence on the neural patterns of empathy. This dissertation also identified specific neural patterns underlying altered empathy and conflict resolution patterns in autistic adults.</p><p><br></p>
