Reward and empathy in autism
Lead Research Organisation:
University of Reading
Department Name: Sch of Psychology and Clinical Lang Sci
Abstract
Empathy is a natural capacity hardwired into the human brain that we use to understand others emotions and respond appropriately to them. We automatically smile on seeing a baby smile and feel our heart beat faster as a runner dashes to a close finish. This automatic mimicking is a simple measure of how much we empathise with what we are seeing. People with autism do not tend to show this automatic mimicry, and score poorly on other measures of empathy. One explanation for low empathy in autism is that people with autism do not empathise with others because they do not find social stimuli (e.g. human faces) innately pleasing/rewarding. An alternative explanation suggests quite the opposite, in that people with autism do not find social stimuli rewarding because of their lack of empathy.
The proposed research will test the relationship between these two hypotheses in a sample of typical adults, and in a sample of adults with autism, by measuring the activity of their facial muscles (facial Electromyography (EMG)) and brains (functional MRI), while they watch emotion expressions of other people. Facial EMG provides a direct measure of automatic mimicking, by measuring the minute changes in the activity of facial muscles. Functional MRI provides a direct method to measure the real-time activity of the brain regions involved in processing rewards and mimicking. Specifically, these experiments will test
a) if increasing the reward value of a face leads to increased automatic mimicking of the face,
b) if mimicking target faces makes them more rewarding than non-mimicked faces, and
c) what the differences are in the above processes between people with and without autism.
These studies would lead to a better understanding of the nature of empathy and its connection with reward, and contribute to understanding the causal mechanisms that underlie atypical social behaviour in autism. Current therapies for autism rely on various forms of reward conditioning, where people with autism are rewarded for certain types of behaviour. However, how reward conditioning relates to social behaviour is largely unknown. By systematically examining the link between these two processes, this research could potentially inform and enhance the development of therapies for autism.
The proposed research will test the relationship between these two hypotheses in a sample of typical adults, and in a sample of adults with autism, by measuring the activity of their facial muscles (facial Electromyography (EMG)) and brains (functional MRI), while they watch emotion expressions of other people. Facial EMG provides a direct measure of automatic mimicking, by measuring the minute changes in the activity of facial muscles. Functional MRI provides a direct method to measure the real-time activity of the brain regions involved in processing rewards and mimicking. Specifically, these experiments will test
a) if increasing the reward value of a face leads to increased automatic mimicking of the face,
b) if mimicking target faces makes them more rewarding than non-mimicked faces, and
c) what the differences are in the above processes between people with and without autism.
These studies would lead to a better understanding of the nature of empathy and its connection with reward, and contribute to understanding the causal mechanisms that underlie atypical social behaviour in autism. Current therapies for autism rely on various forms of reward conditioning, where people with autism are rewarded for certain types of behaviour. However, how reward conditioning relates to social behaviour is largely unknown. By systematically examining the link between these two processes, this research could potentially inform and enhance the development of therapies for autism.
Technical Summary
Autism Spectrum Conditions (ASC) are a set of neurodevelopmental conditions marked by deficits in empathy, i.e. the ability to understand other peoples mental states and emotions and respond appropriately to them. The causes for this deficit in empathy is poorly understood. One model proposes that people with ASC do not empathise with social stimuli because they do not find them rewarding. An alternative model proposes that the lack of reward in response to social stimuli is, in fact, a consequence of the lack of empathy. In order to test these two models, it is imperative to clarify the normative relationship between empathy and reward. The proposed research will examine this relationship in a sample of typical adults, and a sample of adults with ASC, using facial Electromyography (EMG) and functional MRI (fMRI). This will be achieved through the following three experimental aims:
1) To test if varying the reward value associated with specific social stimuli (e.g. faces) leads to increased facial mimicry, a biomarker of empathy. Different neutral faces will be paired with high/low reward values in an implicit conditioned learning paradigm. This will then be followed by passive observation of emotion expressions of the conditioned stimuli identities, while a) facial muscular activity (using EMG) and b) brain activity (using fMRI) will be recorded from participants. This will test whether automatic mimicry, as measured by the activity of a) congruent facial muscles, and b) brain regions involved in empathy (e.g. Inferior Frontal Gyrus), vary as a function of the reward value of social stimuli.
2) To test if mimicking certain faces makes them more rewarding to participants. Participants will be asked to mimic or simply observe a set of faces presented in the first part of the experiment. In the second part they will freely view emotion expressions of these faces, while brain activity will be recorded using fMRI. This will test if neural regions involved in reward processing (e.g. ventral striatum) are more active for mimicked vs nonmimicked faces.
3) Finally, experiments 1) and 2) will be repeated in a set of adults with ASC, to test which of the two models described earlier holds true for this group.
These studies will shed new light on the causal pathways and neural mechanisms underlying the abnormal social behaviour in ASC. This knowledge stands to inform and enhance the development of therapies for ASC, that rely on various forms of reward conditioning.
1) To test if varying the reward value associated with specific social stimuli (e.g. faces) leads to increased facial mimicry, a biomarker of empathy. Different neutral faces will be paired with high/low reward values in an implicit conditioned learning paradigm. This will then be followed by passive observation of emotion expressions of the conditioned stimuli identities, while a) facial muscular activity (using EMG) and b) brain activity (using fMRI) will be recorded from participants. This will test whether automatic mimicry, as measured by the activity of a) congruent facial muscles, and b) brain regions involved in empathy (e.g. Inferior Frontal Gyrus), vary as a function of the reward value of social stimuli.
2) To test if mimicking certain faces makes them more rewarding to participants. Participants will be asked to mimic or simply observe a set of faces presented in the first part of the experiment. In the second part they will freely view emotion expressions of these faces, while brain activity will be recorded using fMRI. This will test if neural regions involved in reward processing (e.g. ventral striatum) are more active for mimicked vs nonmimicked faces.
3) Finally, experiments 1) and 2) will be repeated in a set of adults with ASC, to test which of the two models described earlier holds true for this group.
These studies will shed new light on the causal pathways and neural mechanisms underlying the abnormal social behaviour in ASC. This knowledge stands to inform and enhance the development of therapies for ASC, that rely on various forms of reward conditioning.
