Poster D30, Monday, March 27, 8:00 – 10:00 am, Pacific Concourse
Mirroring multiple agents at the same time: An fMRI study
Emiel Cracco1, Christian Keysers2, Amanda Clauwaert1, Marcel Brass1; 1Ghent University, 2Netherlands Institute for Neuroscience
There is now converging neural evidence that observed actions are mirrored in the sensorimotor system of the observer. However, this research has mainly focused on situations where the observer views a single agent. We were interested in how the mirror neuron system (MNS) responds to seeing multiple agents. To this end, participants observed two right hands that independently performed either one of three gestures (A, B, or C) or no gesture (N). A univariate analysis of the data indicated stronger activation in the MNS when seeing two simultaneous gestures compared with seeing a single gesture. In addition, a representational similarity analysis showed that both gestures were represented at the same time in the MNS. Specifically, this analysis revealed a stronger correlation between the activation patterns corresponding to seeing two different gestures and to seeing a single gesture when there was overlap between the gestures (e.g. A+B and A+N) compared with when there was no overlap (e.g. A+B and C+N). Based on these findings, it was reasoned that the simultaneous representation of two different gestures in the MNS should trigger activation in brain regions related to response conflict because these gestures cannot be executed at the same time. In support of this idea, increased activation in the anterior cingulate cortex was found in the A+B condition compared with the A+A condition. Together, these findings support the hypothesis that the human MNS is able to incorporate multiple observed actions at the same time.
Topic Area: EMOTION & SOCIAL: Other