Abstract
Biological motions transfer important social information, playing a critical role in our life. Previous studies suggested that human mirror neuron system (hMNS) gets involved in the understanding of biological motion. It has been demonstrated that the mu (8–12 Hz) range, which is suggested to have a direct link with hMNS, is significantly suppressed when perceiving biological motions relative to non-biological motions. However, all previous studies addressing biological motions investigated their mechanisms at a perceptual stage (e.g., extracting social information from a displayed biological motion). In many situations we need to keep the biological motion information in working memory to fulfill tasks, yet, to our knowledge, how the biological motions are retained in working memory remains unknown. Here we explored this issue in two experiments, by adopting point-light displays as the stimuli of interest in a change-detection task. The memory load of biological motions was manipulated. We found that the amplitude suppression of mu range was modulated by the memory load: the amplitude suppression increased as the memory load rose, but leveled off at 4 biological motions. Moreover, the number of biological motions retained in working memory is positively correlated with the amplitude suppression of mu range. These results suggest that hMNS plays a critical role in retaining biological motion in working memory, by rehearsing the biological motions via the mu range.
Meeting abstract presented at VSS 2013