Contextual Modulation of Mirror and Countermirror Sensorimotor Associations

Automatic imitation – the unintended copying of observed actions - is thought to be a behavioural product of the mirror neuron system (MNS). Evidence that the MNS develops through associative learning comes from previous research showing that automatic imitation is attenuated by counter-mirror training, in which the observation of one action is paired contingently with the execution of a different action. If the associative account of the MNS is correct, counter-mirror training should show context-specificity, because countermirror associations render action stimuli ambiguous, and ambiguity promotes contextual control. Two experiments are reported which confirm this prediction. In Experiment 1 we found less residual automatic imitation when human participants were tested in their counter-mirror training context. In Experiment 2, sensorimotor training where participants made action responses to novel abstract stimuli was insensitive to the same context manipulation, confirming that the former result was not a procedural artefact. Contextual modulation may enable the MNS to function effectively in spite of the fact that action observation often excites multiple conflicting MNS responses