Eye gaze metrics reflect a shared motor representation for action observation and movement imagery

Action observation (AO) and movement imagery (MI) have been reported to share similar neural networks. This study investigated the congruency between AO and MI using the eye gaze metrics, dwell time and fixation number. A simple reach-grasp-place arm movement was observed and, in a second condition, imagined where the movement was presented from the first person perspective (1PP) and the third person perspective (3PP). Dwell time and number of fixations were calculated for whole scene and regions of interest (ROIs). For whole scene, no significant differences were found in the number of fixations for condition (AO, MI) or perspective. Dwell time, however, was significantly longer in AO than MI. For ROIs, the number of fixations was significantly greater in 1PP than 3PP. The data provide support for congruence between motor simulation states but also indicate some functional differences