Mirror-touch synaesthesia: Difficulties inhibiting the other.
Santiesteban I., Bird G., Tew O., Cioffi MC., Banissy MJ.
Individuals with mirror touch synaesthesia (MTS) experience touch on their own body when observing others being touched. A recent account proposes that such rare experiences could be linked to impairment in self-other representations. Here we tested participants with MTS on a battery of social cognition tests and found that compared to non-synaesthete controls, the MTS group showed impairment in imitation-inhibition but not in visual perspective taking or theory of mind. Although all of these socio-cognitive abilities rely on the control of self-other representations, they differ as to whether the self, or the other, should be preferentially represented. For imitation-inhibition, representations of the other should be inhibited and self-representations should be enhanced, whereas the opposite is true for visual perspective taking and theory of mind. These findings suggest that MTS is associated with a specific deficit in inhibiting representation of other individuals and shed light on the fractionability of processes underlying typical social cognition.