Leslie Kenneth R, Johnson-Frey Scott H, Grafton Scott T
Department of Psychological and Brain Sciences and Center for Cognitive Neurosciences, Dartmouth College, Hanover NH 03755, USA.
Neuroimage. 2004 Feb;21(2):601-7. doi: 10.1016/j.neuroimage.2003.09.038.
Empathy requires the ability to map the feelings of others onto our own nervous system. Until recently, there was no plausible mechanism to explain how such a mapping might occur. The discovery of mirror neurons, however, suggests that the nervous system is capable of mapping the observed actions of others onto the premotor cortex of the self, at least for reaching and grasping movements. Is there a mirroring system for emotive actions, such as facial expression? Subjects (N = 15; all right-handed; eight men, seven women) watched movies of facial expressions (smile or frown) and hand movements (move index or middle finger) while brain activity was imaged using functional magnetic resonance imaging (fMRI). Subjects watched the movies under three different conditions: passive viewing, active imitation, and an active motor control. Subjects also performed a verb generation task to functionally identify language-processing areas. We found evidence for a common cortical imitation circuit for both face and hand imitation, consisting of Broca's area, bilateral dorsal and ventral premotor areas, right superior temporal gyrus (STG), supplementary motor area, posterior temporo-occipital cortex, and cerebellar areas. For faces, passive viewing led to significant activation in the right ventral premotor area, whereas imitation produced bilateral activation. This result is consistent with evidence for right hemisphere (RH) dominance for emotional processing, and suggests that there may be a right hemisphere mirroring system that could provide a neural substrate for empathy.
同理心需要具备将他人的感受映射到我们自身神经系统的能力。直到最近，还没有合理的机制来解释这种映射是如何发生的。然而，镜像神经元的发现表明，神经系统能够将观察到的他人动作映射到自身的运动前区皮质，至少对于伸手和抓握动作是如此。对于诸如面部表情等情感动作，是否存在一个镜像系统呢？研究对象（N = 15；均为右利手；8名男性，7名女性）在通过功能磁共振成像（fMRI）对大脑活动进行成像时，观看面部表情（微笑或皱眉）和手部动作（食指或中指移动）的影片。研究对象在三种不同条件下观看影片：被动观看、主动模仿和主动运动控制。研究对象还执行了一个动词生成任务，以从功能上识别语言处理区域。我们发现了面部和手部模仿存在共同皮质模仿回路的证据，该回路由布洛卡区、双侧背侧和腹侧运动前区、右侧颞上回（STG）、辅助运动区、颞枕后皮质和小脑区域组成。对于面部，被动观看导致右侧腹侧运动前区显著激活，而模仿则产生双侧激活。这一结果与情感处理右半球（RH）优势的证据一致，并表明可能存在一个右半球镜像系统，它可以为同理心提供神经基础。
