人类社会认知的神经机制:来自社会脑研究的证据

The Neural Mechanisms of Human Social Cognition:Evidence from The Social Brain

社会认知是指从环境互动的过程中推测他人意图、情感和思想等内部状态的心理加工过程。社会脑假说认为,包括人类在内的灵长类大脑内肯定存在着一个旨在认识和理解他人表情的神经机制,在社会交往中通过该中枢迅速处理与他人相互作用的各种信息。本文通过回顾社会脑的构成与基本功能,镜像神经元的发现及功能,以及社会脑、镜像神经元对社会认知影响的相关研究,提出了人类社会认知不同于其他物种的三个主要区别。

Social cognition in humans is distinguished by psychological processes that allow us to make inferences about what is going on inside other people—their intentions,feelings,and thoughts.Some of these processes likely account for aspects of human social behavior that is unique,such as our culture and civilization. The social brain hypothesis attempts to explain the extraordinary size and complexity of the human brain by appealing to particular pressures that a species adapted to social interaction would have had to face,ranging from deception to cooperation to ways of obtaining food and ensuring offspring.In part,this is a chicken-and-egg question：Did greater general cognitive abilities and intelligence drive our social cognition,or did social cognition enable our intelligence in general？ The evolution of the human brain to its present size 1.3 kg is notable for tremendous acceleration on an evolutionarily quite recent timescale,with major increases within less than a million years ago. One feature of human cognition is a representation of both sensory and motor information in order to permit more flexible behavior.For instance,a remapping of interoceptive information about the state of one＇ s own body may allow humans and other primates to construct explicit representations of how they feel,and to know and regulate consequently how they feel in a flexible way. This remapping has been proposed to rely on relays of interoceptive processing into the insula,and a further remapping within the anterior insula is thought to consolidate body state information about oneself with social and contextual information to provide a neural substrate of the conscious experience of emotions.This region of the brain has been found to be activated in a large number of studies that involve other people,or information about other people,as the stimuli. Emotions motivate behavior;thus,simulating other people＇s emotions provides us with one strategy for predicting what they are likely to do.A complementary strategy is to simulate aspects of the premotor representations that would normally accompany goal-directed behavior,a mechanism supported by finding representations,at the systems and cellular level,and that are engaged both when we plan to execute an action ourselves and when we observe another person carry out the same action.Although some of these＂mirror＂representations respond only to viewing a very specificaction,the majority can abstract from the particulars of any specificaction or even sensory modality to encode goal-directed intentions. With regard the role of the medial prefrontal cortex in theory-of-mind abilities,it＇s less controversial as it is consistently activated when we think about other people＇s internal states.This region is activated when we need to infer the current beliefs of another person,evaluate their longer-term traits and dispositions,and think about our own minds.