Stephen Wood¹ (), Jonathan J Marotta¹; ¹Perception and Action Lab, University of Manitoba

Motor imagery (MI) refers to the internal simulation or rehearsal of movements without physical execution. According to motor simulation theory, MI is functionally equivalent to motor performance, as it evokes the same cognitive and neuronal processes involved in executing movements. One significant difference between MI and execution is the availability of online sensory feedback for their performance. Movements rely on online visual and proprioceptive feedback to monitor and correct ongoing actions. Alternatively, MI does not produce the actions required to receive online sensory feedback. Due to this difference, sensory and sensorimotor networks represent one area in which MI may not accurately replicate the processes involved in motor performance. The present study evaluated whether online sensory feedback is involved in MI. Fifty participants completed the Hand Laterality Judgement Task (HLJT) across four sensory feedback conditions, including a control, no-vision, disrupted-proprioception, and no-vision + disrupted-proprioception condition. The HLJT is a common measure of MI where participants identify the laterality of a hand stimulus as quickly and accurately as possible. To make their judgements, participants tend to imagine moving their own hand into the orientation of the hand stimulus presented to them, especially when identifying palm-view stimuli. Visual and proprioceptive feedback were manipulated by placing a box over participants’ hands and applying transcutaneous electrical pulses to the median and ulnar nerves, respectively. Each participant completed 64 trials of the HLJT in all four sensory feedback conditions for a total of 256 trials. This experiment found that participants took longer to identify the laterality of hands when visual and proprioceptive feedback were disrupted. Moreover, reaction time increases were exclusively observed for palm-view stimuli. Overall, the results of this experiment indicate: 1) Online sensory feedback is used to simulate actions effectively; 2) both visual and proprioceptive feedback contribute to MI performance in the HLJT.

Acknowledgements: This research is supported by the University of Manitoba Psychology Graduate Fellowship, The University of Manitoba Graduate Fellowship, and an NSERC Discovery Grant.