Department of Psychology, Hebrew University, Jerusalem, Israel.
Neuroimage. 2011 Oct 1;58(3):895-904. doi: 10.1016/j.neuroimage.2011.06.060. Epub 2011 Jun 30.
Mu rhythms are EEG oscillations in the 8-13 Hz recorded at sites located roughly over the sensory-motor cortex. There is reliable evidence that the amplitude of mu rhythms is reduced when the participant performs a motor act (mu suppression). Recent studies found mu suppression not only in response to actual movements but also while the participant observes actions executed by someone else. This finding putatively associates the mu suppression to the activity of a mirror neurons system which, in humans, has been suggested to contribute to social skills. In the present study we explored the effects of different levels of social interaction on mu suppression. Participants observed dynamic displays of hand gestures performing actions used in the Rock-Scissors-Paper game. In different blocks, participants passively viewed identical video clips with no game context and in the context of a game, or while being actually engaged in the game either by imagining actions or by actual playing. As a baseline for calculating mu suppression we used a dynamic display of a rolling ball. In addition, to isolate the social aspect of the actual movements, participants performed the same acts outside the game context. Mu suppression was larger while participants were engaged in the social game than when they passively looked at the "opponent" actions or when they performed movements without the game context. This effect was found while viewing the opponent play as well as while actually playing, which supports the view that mu suppression is affected not only by motion, but also by the social context of the motion. However, we did not find differences in mu suppression between perception segments in which the participant did not actually play. Furthermore, in all perception segments occipital alpha suppression was more robust than mu suppression suggesting the involvement of a strong attentional component. While actually playing, however, mu suppression was stronger than alpha suppression.
mu 节律是在位于感觉运动皮层附近的位置记录的 8-13 Hz 的 EEG 振荡。有可靠的证据表明，当参与者执行运动动作时，mu 节律的幅度会降低（mu 抑制）。最近的研究发现，mu 抑制不仅在对实际运动的反应中，而且在参与者观察其他人执行的动作时也会发生。这一发现推测 mu 抑制与镜像神经元系统的活动有关，在人类中，镜像神经元系统被认为有助于社交技能。在本研究中，我们探讨了不同程度的社交互动对 mu 抑制的影响。参与者观察执行石头剪刀布游戏动作的动态手势显示。在不同的块中，参与者被动观看没有游戏背景的相同视频剪辑，或者在游戏背景中观看，或者在实际参与游戏时通过想象动作或实际玩游戏来观看。作为计算 mu 抑制的基线，我们使用了滚动球的动态显示。此外，为了分离实际动作的社交方面，参与者在游戏之外执行相同的动作。当参与者参与社交游戏时，他们的 mu 抑制比被动观看“对手”动作或在没有游戏背景的情况下执行动作时更大。当观看对手比赛和实际比赛时都发现了这种效果，这支持了 mu 抑制不仅受运动影响，还受运动的社会背景影响的观点。然而，我们没有发现参与者没有实际参与的感知段之间的 mu 抑制差异。此外，在所有感知段中，枕部 alpha 抑制比 mu 抑制更强，这表明注意力成分较强。然而，当实际玩游戏时，mu 抑制比 alpha 抑制更强。
