Authors:

MOUTSOPOULOU, K., MANLY, T. & CUSACK, R.

Reference:

Year of publication:

2008

CBU number:

6872

Abstract:

The mirror neuron (MN) system is activated during action execution and observation. Although studies have investigated many of its properties, it has not been established whether the MN response is automatic or modulated by attention. There may be benefits in preventing irrelevant stimuli from influencing processing of attended actions. This fMRI study investigated modulatory effects of attention on MN function, using videos of biological actions (arm or leg) and non-biological equivalents (spatially and temporally matched). Trials consisted of two overlaid clips (both biological, both non-biological, or one of each), and subjects attended to one clip while performing a target detection task (observation). Hand and foot movement execution trials were included for localization of the MN system. Relative to control stimuli, observation of arm actions activatedthe Superior Temporal Sulcus (STS, implicated in processing biological motion) and MN regions in motor and parietal cortex, which were also active during execution. Leg stimuli yielded less reliable activity. Crucially, attention modulated the response in MN regions (motor cortex, left parietal lobe) and in bilateral STS. However, right STS and a right superior parietal region remained activated even in the unattended condition. The results indicate differential effects of attention within the MN network.