28/09/19
In the past two decades, research has shown the contribution of the somatosensory cortex to emotion recognition, supporting the embodied emotion hypothesis. Atypical processing of emotional expressions in autism spectrum disorder (ASD) has been mainly investigated at a visual level, here we aim to test if ASD individuals show atypical responses in the somatosensory cortex (SCx) during emotion recognition, compared to typically developed (TD) individuals. We presented neutral, afraid and happy faces and asked our participants to pay attention to the emotional expression (emotion task) or the gender (control task) while recording their brain activity with a 64-channels EEG. We measured the visual evoked potentials (VEPs) over the occipital lobe and the somatosensory evoked potentials (SEPs) over the SCx. SEPs were evoked by applying a tactile stimulation on their index finger during the visual processing. To isolate the somatosensory activity related to emotion processing from visual carryover effects, we subtracted the neural responses recorded in the visual condition from activity in the visuo-tactile condition (Sel et al., 2014). Interestingly, we found significant task*group and task*group*region interactions in the 100-130ms time window (P100), showing enhanced difference between the two groups in the emotion task. Moreover, SEPs amplitude evoked during the emotion task correlates with autistic traits measured by Autism Quotient (AQ) and Social Responsiveness Scale (SRS). EEG signal was source localized in the right primary somatosensory cortex. Our study provides novel evidence of atypical responses in the somatosensory cortex during recognition of emotional expressions in individuals with ASD. Further research will focus on modelling an extended network of areas underlying the observed effects with Dynamic Causal Modelling (Friston et al. 2002).
Presentations of New PhD students
Speaker’s Corner:
Prof. Aglioti - Welcome back and welcome on board!