Perry Anat, Saunders Samantha N, Stiso Jennifer, Dewar Callum, Lubell Jamie, Meling Torstein R, Solbakk Anne-Kristin, Endestad Tor, Knight Robert T
University of California, Berkeley, CA 94720, USA.
University of Oslo, Oslo, Norway.
Brain. 2017 Apr 1;140(4):1086-1099. doi: 10.1093/brain/awx031.
Humans are highly social beings that interact with each other on a daily basis. In these complex interactions, we get along by being able to identify others' actions and infer their intentions, thoughts and feelings. One of the major theories accounting for this critical ability assumes that the understanding of social signals is based on a primordial tendency to simulate observed actions by activating a mirror neuron system. If mirror neuron regions are important for action and emotion recognition, damage to regions in this network should lead to deficits in these domains. In the current behavioural and EEG study, we focused on the lateral prefrontal cortex including dorsal and ventral prefrontal cortex and utilized a series of task paradigms, each measuring a different aspect of recognizing others' actions or emotions from body cues. We examined 17 patients with lesions including (n = 8) or not including (n = 9) the inferior frontal gyrus, a core mirror neuron system region, and compared their performance to matched healthy control subjects (n = 18), in behavioural tasks and in an EEG observation-execution task measuring mu suppression. Our results provide support for the role of the lateral prefrontal cortex in understanding others' emotions, by showing that even unilateral lesions result in deficits in both accuracy and reaction time in tasks involving the recognition of others' emotions. In tasks involving the recognition of actions, patients showed a general increase in reaction time, but not a reduction in accuracy. Deficits in emotion recognition can be seen by either direct damage to the inferior frontal gyrus, or via damage to dorsal lateral prefrontal cortex regions, resulting in deteriorated performance and less EEG mu suppression over sensorimotor cortex.
人类是高度社会化的生物，每天都在相互交流互动。在这些复杂的互动中，我们通过能够识别他人的行为并推断他们的意图、想法和感受来与他人相处。解释这种关键能力的主要理论之一假定，对社会信号的理解基于一种原始倾向，即通过激活镜像神经元系统来模拟观察到的行为。如果镜像神经元区域对动作和情感识别很重要，那么该网络中区域的损伤应该会导致这些方面的缺陷。在当前的行为和脑电图研究中，我们聚焦于包括背侧和腹侧前额叶皮质在内的外侧前额叶皮质，并采用了一系列任务范式，每个范式测量从身体线索识别他人动作或情感的不同方面。我们检查了17名有损伤的患者，其中8名患者的损伤包括镜像神经元系统核心区域额下回，9名患者的损伤不包括额下回，并将他们在行为任务和测量μ波抑制的脑电图观察 - 执行任务中的表现与匹配的健康对照受试者（18名）进行比较。我们的结果支持了外侧前额叶皮质在理解他人情感中的作用，表明即使是单侧损伤也会导致涉及识别他人情感的任务在准确性和反应时间上出现缺陷。在涉及动作识别的任务中，患者的反应时间普遍增加，但准确性没有降低。情感识别缺陷既可以通过直接损伤额下回，也可以通过损伤背外侧前额叶皮质区域来体现，这会导致表现变差以及感觉运动皮质上脑电图μ波抑制减少。
