Humans are social beings. Most of us find looking at, hearing, and interacting with other humans to be a rewarding experience. One theoretical account of autism is based on the observation that individuals with ASD often do not find social stimuli and interactions to be rewarding. This account suggests that social behavioural difficulties in ASD are driven by a deficit in reward processing from social stimuli. In our research, we study how reward influences a fundamental aspect of human social behaviour, i.e. spontaneous facial mimicry. Spontaneous facial mimicry is an integral part of everyday social interactions, e.g. we smile automatically when we see others smile at us. Individuals with ASD commonly show reduced spontaneous facial mimicry.
These two processes of mimicry and reward are intricately linked from early on in human development. Mothers commonly mimic their children, and the children mimic back. This cycle of mimicry helps build social bonds, in children as well as in adults. As adults, we tend to prefer individuals who mimic us more, and, mimic those who we prefer more. We study these links between reward and mimicry using a range of techniques that measure physiological response (using facial EMG), brain activity (using fMRI), eye movements (using eye-tracking), and overt behaviour. The emerging picture from our research suggests that autism represent a weakening of the bidirectional links between reward and mimicry. Rather than there being a core problem in the act of mimicry per se, or responding to social rewards, autistic symptoms might be more representative of an atypical connection between neural systems involved in reward processing and those underlying mimicry.