示能性:基于镜像神经元视角的理解

示能性(affordance)概念解释了人的行为与物体功能之间互动、互补的关系。但是,有关示能性生理基础却很少被提及。镜像神经元的发现为示能性生理基础提供了可能的解释。文章根据研究将示能性分为结构示能性和功能示能性,探讨了不同示能性和镜像神经元之间的关系,并提出不同神经通路中的镜像神经元是示能性生理基础的结论。背-背侧分流中的镜像神经元是结构示能性的神经基础,而腹-背侧分流中的镜像神经元是功能示能性的神经基础。

Affordance: a Perspective from Mirror Neurons

In 1979, Gibson first introduced the term “affordance”, which refers to the behavior possibility that environment provide to in the process of the interaction between individuals and environment. The relationship between the objects and mind caused attention and researches in the field of cognitive and human-computer interaction. Riches of evidence on affordance come from the field of neuroscience and behavioral science. On the neuroscience side, studies of brain imaging revealed that when individual was observing an object some cortexes active. For example, in the process of perception of tools’ affordance promoter and parietal cortex activate. And on the behavioral side, compatibility paradigms were used to investigate the issues of affordance. For example, individual with precision grip for small objects responded faster than with power grip. However, the physiological basis of affordance remains unknown. Fortunately, the finding of mirror neurons contributes to explaining the physiological mechanisms of affordance. Mirror neurons refer to the neurons that fire when the animal observe and act the same action as what others perform. These neurons were observed not only in monkey not but also in humans. In humans, the cortexes involving in mirror neurons are premotor cortex and the inferior parietal lobule. The potential relationship between mirror neurons and affordance provide a new view to further answer this question and to understand the physiological basis of the affordance. Further explore more accurate neural basis of affordance from the perspective of mirror neurons is beneficial for us to deeply make sense of the phenomenon of human psychological behavior. Objects do not elicit only one kind of affordance but multiple affordances. An object activates affordance related with grasping or touching (such as object size, orientation) and affordance related to how to facilitate its function. Firstly, different kinds of affordances ranging from structural affordance and functional affordance are introduced. Structural affordance relates to properties of objects that can vary (such as the orientation and angle of an object), and functional affordance relates to properties of objects that keep constant between different experiences of individuals (such as the way to catch a cup). Then, the relations between different kind of affordance and mirror neurons are analyzed. Mirror neurons are the physiological basis of behavioral goal and affordance can be regarded as the behavioral possibility that can be used by humans, the mirror neuron system includes the neural pathways of the model that illustrate affordance and the model of the mirror neurons also contains the process of extraction affordance. So, mirror neurons may be the physiological basis of affordance. Thirdly, the assumptions of the mirror neurons existing in different neural pathways are the physiological basis of affordance are proposed. Anatomical studies pointed out that affordance related to the pathways in dorsal stream and two different streams (dorso-dorsal stream and ventro-dorsal stream) exist in dorsal stream. Furthermore, dorso-dorsal stream subserves the on-line visual information of objects and ventro-dorsal stream facilitates how to use the objects. So it is suggested that mirror neurons in the dorso-dorsal stream subserve structural affordance and mirror neurons in the ventro-dorsal stream subserve functional affordance.