How and why do infants imitate? An ideomotor approach to social and imitative learning in infancy (and beyond)

It has been proposed that already in infancy, imitative learning plays a pivotal role in the acquisition of knowledge and abilities. Yet the cognitive mechanisms underlying the acquisition of novel action knowledge through social learning have remained unclear. The present contribution presents an ideomotor approach to imitative learning (IMAIL) in infancy (and beyond) that draws on the ideomotor theory of action control and on recent findings of perception–action matching. According to IMAIL, the central mechanism of imitative and social learning is the acquisition of cascading bidirectional action–effect associations through observation of own and others’ actions. First, the observation of the visual effect of own actions leads to the acquisition of first-order action–effect associations, linking motor codes to the action’s typical visual effects. Second, observing another person’s action leads to motor activation (i.e., motor resonance) due to the first-order associations. This activated motor code then becomes linked to the other salient effects produced by the observed action, leading to the acquisition of (second-order) action–effect associations. These novel action–effect associations enable later imitation of the observed actions. The article reviews recent behavioral and neurophysiological studies with infants and adults that provide empirical support for the model. Furthermore, it is discussed how the model relates to other approaches on social-cognitive development and how developmental changes in imitative abilities can be conceptualized.     

重解动作理解的“戈尔迪之结”:镜像神经元祛魅

"动作理解"一直被视为镜像神经元功能最为保守的假设,同时也是证据链最为强健的领域之一,但其概念内涵却始终如同古希腊神话中的"戈尔迪之结"一般没有得到厘清。目前,动作理解的紧缩解释正在面临严峻的挑战。来自实验室检验与哲学拷问的证据倾向于认为,镜像神经元活动构成动作理解的观点是一种"循环论证",前者至多只能算作产生动作理解的附带原因,而不是必要与充分原因。将广义的动作分成运动、运动动作与运动动作链可以有效地澄清实现理解不同层次的动作需要具备哪些条件。回应质疑并为辩护自身立场指明前进方向,是重解动作理解"戈尔迪之结"的起点,将对镜像神经元的科学祛魅产生奠基性的影响。     

Does motor interference arise from mirror system activation? The effect of prior visuo-motor practice on automatic imitation

Action perception may involve a mirror-matching system, such that observed actions are mapped onto the observer’s own motor representations. The strength of such mirror system activation should depend on an individual’s experience with the observed action. The motor interference effect, where an observed action interferes with a concurrently executed incongruent action, is thought to arise from mirror system activation. However, this view was recently challenged. If motor interference arises from mirror system activation, this effect should be sensitive to prior sensorimotor experience with the observed action. To test this prediction, we measured motor interference in two groups of participants observing the same incongruent movements. One group had received brief visuo-motor practice with the observed incongruent action, but not the other group. Action observation induced a larger motor interference in participants who had practiced the observed action. This result thus supports a mirror system account of motor interference.     

The self in action effects: selective attenuation of self-generated sounds

The immediate experience of self-agency, that is, the experience of generating and controlling our actions, is thought to be a key aspect of selfhood. It has been suggested that this experience is intimately linked to internal motor signals associated with the ongoing actions. These signals should lead to an attenuation of the sensory consequences of one’s own actions and thereby allow classifying them as self-generated. The discovery of shared representations of actions between self and other, however, challenges this idea and suggests similar attenuation of one’s own and other’s sensory action effects.Here, we tested these assumptions by comparing sensory attenuation of self-generated and observed sensory effects. More specifically, we compared the loudness perception of sounds that were either self-generated, generated by another person or a computer. In two experiments, we found a reduced perception of loudness intensity specifically related to self-generation. Furthermore, the perception of sounds generated by another person and a computer did not differ from each other. These findings indicate that one’s own agentive influence upon the outside world has a special perceptual quality which distinguishes it from any sort of external influence, including human and non-human sources. This suggests that a real sense of self-agency is not a socially shared but rather a unique and private experience.     

Emotion perception from a componential perspective

The common conceptual understanding of emotion is that they are multi-componential, including subjective feelings, appraisals, psychophysiological activation, action tendencies, and motor expressions. Emotion perception, however, has traditionally been studied in terms of emotion labels, such as “happy”, which do not clearly indicate whether one, some, or all emotion components are perceived. We examine whether emotion percepts are multi-componential and extend previous research by using more ecologically valid, dynamic, and multimodal stimuli and an alternative response measure. The results demonstrate that observers can reliably infer multiple types of information (subjective feelings, appraisals, action tendencies, and social messages) from complex emotion expressions. Furthermore, this finding appears to be robust to changes in response items. The results are discussed in light of their implications for research on emotion perception.     

Emergence of self and other in perception and action: an event-control approach

The present paper analyzes the regularities referred to via the concept 'self.' This is important, for cognitive science traditionally models the self as a cognitive mediator between perceptual inputs and behavioral outputs. This leads to the assertion that the self causes action. Recent findings in social psychology indicate this is not the case and, as a consequence, certain cognitive scientists model the self as being epiphenomenal. In contrast, the present paper proposes an alternative approach (i.e., the event-control approach) that is based on recently discovered regularities between perception and action. Specifically, these regularities indicate that perception and action planning utilize common neural resources. This leads to a coupling of perception, planning, and action in which the first two constitute aspects of a single system (i.e., the distal-event system) that is able to pre-specify and detect distal events. This distal-event system is then coupled with action (i.e., effector-control systems) in a constraining, as opposed to 'causal' manner. This model has implications for how we conceptualize the manner in which one infers the intentions of another, anticipates the intentions of another, and possibly even experiences another. In conclusion, it is argued that it may be possible to map the concept 'self' onto the regularities referred to in the event-control model, not in order to reify 'the self' as a causal mechanism, but to demonstrate its status as a useful concept that refers to regularities that are part of the natural order.     

The influence of motor expertise and motor experience on action and actor recognition

Two experiments examined whether different levels of motor and visual experience influence action perception and whether this effect depends on the type of perceptual task. Within an action recognition task (Experiment 1), professional basketball players and novice college students were asked to identify basketball dribbles from point-light displays. Results showed faster reaction times and greater accuracy in experts, but no advantage when observing either own or teammates’ actions compared with unknown expert players. Within an actor recognition task (Experiment 2), the same expert players were asked to identify the model actors. Results showed poor discrimination between teammates and players from another team, but a more accurate assignment of own actions to the own team. When asked to name the actor, experts recognised themselves slightly better than teammates. Results support the hypothesis that motor experience influences action recognition. They also show that the influence of motor experience on the perception of own actions depends on the type of perceptual task.     

Practical Perception and Intelligent Action

Perceiving things to be a certain way may in some cases lead directly to action that is intelligent (e.g., skillful, wise, clever, astute). This phenomenon has not often been discussed, though it is of broad philosophical interest. It also raises a difficult question: how can perception produce intelligent action? After clarifying the question—which I call the question of “practical perception”—and explaining what is required for an adequate answer, I critically examine two candidate answers drawn from work on related topics: the first, inspired by Hubert Dreyfus's phenomenological analysis of absorbed coping (and of a piece with James Gibson's theory of affordances), focuses on awareness of situational features; the other, suggested by Gilbert Ryle's classic treatment of knowledge‐how, focuses on possession of behavioral dispositions. I argue that neither approach is adequate. Subsequently, I develop and defend an alternative answer that emphasizes the agent's conceptual understanding.     

镜像神经元的意义

镜像神经元是一种感觉–运动神经元。它的典型特征是在动作观察和动作执行两个阶段皆被激活。多年来, 由于研究伦理的限制, 研究恒河猴时使用的单细胞电极植入方式无法应用于人类, 因而不能确定人类大脑皮层是否也存在着具有同样功能的神经细胞。但是通过脑成像技术, 神经科学家确定人类大脑皮层存在着具有相同或类似功能的脑区, 称为“镜像神经系统”。文章对镜像神经元及其人类镜像神经系统的意义进行了深入分析, 指出：(1)由于镜像机制把动作知觉和动作执行进行匹配, 观察者仅仅通过他人行为的知觉, 就激活了执行这一动作的神经环路, 产生了一种他人动作的具身模拟, 因而可以直接把握他人的行为意图; (2)镜像神经元所表现出来的那种动作知觉与动作执行的双重激活功能支持了身心一体说, 从方法论上证明了身心二元论的缺陷, 为身心的整体观提供了神经生物学的证据; (3)镜像神经机制把他人的动作与自己的运动系统相匹配, 以自身动作的神经环路对他人的动作做出回应, 促进了人际理解和沟通, 成为社会沟通的“神经桥梁”。     

The mirror neuron system and action recognition

Mirror neurons, first described in the rostral part of monkey ventral premotor cortex (area F5), discharge both when the animal performs a goal-directed hand action and when it observes another individual performing the same or a similar action. More recently, in the same area mirror neurons responding to the observation of mouth actions have been also found. In humans, through an fMRI study, it has been shown that the observation of actions performed with the hand, the mouth and the foot leads to the activation of different sectors of Broca's area and premotor cortex, according to the effector involved in the observed action, following a somatotopic pattern which resembles the classical motor cortex homunculus. These results strongly support the existence of an execution-observation matching system (mirror neuron system). It has been proposed that this system is involved in action recognition. Experimental evidence in favor of this hypothesis both in the monkey and humans are shortly reviewed.     

动允直接知觉的共鸣原理

传统认知理论认为我们只能间接知觉动允,而生态认知心理学则认为对动允的知觉是个体与环境信息直接共鸣的过程。生态认知心理学首先判定动允并不是存在于我们头脑中的认识,而是实际存在于个体-环境系统中的事实,对动允的直接知觉就是对动允的检测而非推测,是对动允信息的拾取而非对记忆内容的提取。这种直接知觉表现为身体的相关动作机制（动作神经元、肌肉组织等）与环境中动允信息的共鸣。进化与学习在共鸣的形成与发展中具有重要作用。     

Mirror neurons and the simulation theory of mind-reading

A new class of visuomotor neuron has been recently discovered in the monkey's premotor cortex: mirror neurons. These neurons respond both when a particular action is performed by the recorded monkey and when the same action, performed by another individual, is observed. Mirror neurons appear to form a cortical system matching observation and execution of goal-related motor actions. Experimental evidence suggests that a similar matching system also exists in humans. What might be the functional role of this matching system? One possible function is to enable an organism to detect certain mental states of observed conspecifics. This function might be part of, or a precursor to, a more general mind-reading ability. Two different accounts of mind-reading have been suggested. According to ‘theory theory', mental states are represented as inferred posits of a naive theory. According to ‘simulation theory', other people's mental states are represented by adopting their perspective: by tracking or matching their states with resonant states of one's own. The activity of mirror neurons, and the fact that observers undergo motor facilitation in the same muscular groups as those utilized by target agents, are findings that accord well with simulation theory but would not be predicted by theory theory.     

Empathy constrained: Prejudice predicts reduced mental simulation of actions during observation of outgroups

Perception-action-coupling refers to the vicarious activation of the neural system for action during perception of action, and is considered important for forms of interpersonal sensitivity, including empathy. We hypothesize that perception-action-coupling is limited to the ingroup: neural motor networks will fire upon the perception of action, but only when the object-person belongs to the ingroup; if the object-person belongs to an outgroup these motor neurons will not fire. Using electroencephalographic oscillations as an index of perception-action-coupling, we found exactly this: participants displayed activity over motor cortex when acting and when observing ingroups act, but not when observing outgroups - an effect magnified by prejudice and for disliked groups (South-Asians, then Blacks, followed by East Asians). These findings provide evidence from brain activity for yet another detrimental aspect of prejudice: a spontaneous and implicit simulation of others’ action states may be limited to close others and, without active effort, may not be available for outgroups.     

Do infants provide evidence that the mirror system is involved in action understanding?

The mirror neuron theory of action understanding makes predictions concerning how the limited motor repertoire of young infants should impact on their ability to interpret others’ actions. In line with this theory, an increasing body of research has identified a correlation between infants’ abilities to perform an action, and their ability to interpret that action as goal-directed when performed by others. In this paper, I will argue that the infant data does by no means unequivocally support the mirror neuron theory of action understanding and that alternative interpretations of the data should be considered. Furthermore, some of this data can be better interpreted in terms of an alternative view, which holds that the role of the motor system in action perception is more likely to be one of enabling the observer to predict, after a goal has been identified, how that goal will be attained.     

An information-based approach to action understanding

It has been proposed that the ability to make sense of other agents' behavior relies on the activation of internal mechanisms that map action perception onto action execution. In this study we explored the constraints on this ability introduced by eyeheight-scaled information in the optic array. Short and tall participants provided maximum overhead reaching judgments for themselves and another participant. Perceptual information was manipulated by changing the participants' optically specified eyeheight. Observers were modestly accurate in perceiving maximum overhead reach for themselves and for another actor whose action capabilities differed. Perceived maximum overhead reach increased for both self- and other-judgments when the perceiver's eyeheight was increased. The results suggest an important role of perceptual information that has gone unrecognized in existing accounts of action understanding and prediction.     

From semantics to syntax and back again: argument structure in the third year of life

An essential part of the human capacity for language is the ability to link conceptual or semantic representations with syntactic representations. On the basis of data from spontaneous production, suggested that young children acquire such links on a verb-by-verb basis, with little in the way of a general understanding of linguistic argument structure. Here, we suggest that a receptive understanding of argument structure--including principles linking syntax and conceptual/semantic structure--appears earlier. In a forced-choice pointing task we have shown that toddlers in the third year of life can map a single scene (involving a novel causative action paired with a novel verb) onto two distinct syntactic frames (transitive and intransitive). This suggests that even before toddlers begin generalizing argument structure in their own speech, they have some representation of conceptual/semantic categories, syntactic categories, and a system that links the two.     

The Social Nature of Perception and Action

ABSTRACT— Humans engage in a wide range of social activities. Previous research has focused on the role of higher cognitive functions, such as mentalizing (the ability to infer others' mental states) and language processing, in social exchange. This article reviews recent studies on action perception and joint action suggesting that basic perception–action links are crucial for many social interactions. Mapping perceived actions to one's own action repertoire enables direct understanding of others' actions and supports action identification. Joint action relies on shared action representations and involves modeling of others' performance in relation to one's own. Taking the social nature of perception and action seriously not only contributes to the understanding of dedicated social processes but has the potential to create a new perspective on the individual mind and brain.     

Cognitive and Neural Contributions to Understanding the Conceptual System

ABSTRACT— The conceptual system contains categorical knowledge about experience that supports the spectrum of cognitive processes. Cognitive science theories assume that categorical knowledge resides in a modular and amodal semantic memory, whereas neuroscience theories assume that categorical knowledge is grounded in the brain's modal systems for perception, action, and affect. Neuroscience has influenced theories of the conceptual system by stressing principles of neural processing in neural networks and by motivating grounded theories of cognition, which propose that simulations of experience represent knowledge. Cognitive science has influenced theories of the conceptual system by documenting conceptual phenomena and symbolic operations that must be grounded in the brain. Significant progress in understanding the conceptual system is most likely to occur if cognitive and neural approaches achieve successful integration.     

The role of sensorimotor experience in the development of mimicry in infancy

During social interactions we often have an automatic and unconscious tendency to copy or ‘mimic’ others’ actions. The dominant view on the neural basis of mimicry appeals to an automatic coupling between perception and action. It has been suggested that this coupling is formed through associative learning during correlated sensorimotor experience. Although studies with adult participants have provided support for this hypothesis, little is known about the role of sensorimotor experience in supporting the development of perceptual‐motor couplings, and consequently mimicry behaviour, in infancy. Here we investigated whether the extent to which an observed action elicits mimicry depends on the opportunity an infant has had to develop perceptual‐motor couplings for this action through correlated sensorimotor experience. We found that mothers’ tendency to imitate their 4‐month‐olds’ facial expressions during a parent‐child interaction session was related to infants’ facial mimicry as measured by electromyography. Maternal facial imitation was not related to infants’ mimicry of hand actions, and instead we found preliminary evidence that infants’ tendency to look at their own hands may be related to their tendency to mimic hand actions. These results are consistent with the idea that mimicry is supported by perceptual‐motor couplings that are formed through correlated sensorimotor experience obtained by observing one's own actions and imitative social partners.     

On haptic and motor incorporation of tools and other objects

This article presents a conceptual discussion on the phenomenon of incorporation of tools and other objects in the light of Maine de Biran’s philosophy of the relation between the body and the motor will. Drawing on Maine de Biran’s view of the body as that portion of the material world which directly obeys one’s motor will, as well as on his view (supported by studies in contemporary cognitive science) of active touch as the perceptual modality that is sensitive to objects as fields of forces resisting the perceiver’s movements, we discuss the phenomena of motor incorporation and haptic incorporation, as well as the relation between them. Motor incorporation occurs when something is integrated into the motor system, i.e. when practice enables one to animate an object as directly, effortlessly and fluently as one is able to animate one’s own body. The subject then has the experience of acting there, where the object is located, not at the body–object interface. In order to better understand the phenomenon of motor incorporation, we highlight the phenomenological difference between directly and indirectly moving something. Haptic incorporation occurs when something is integrated into the haptic system, i.e. when an object is used as an instrument for the haptic perception of other objects. Finally, we seek to shed light on the phenomenon of transparency, understanding the transparency acquired by the incorporated object as both a relational property and a matter of degrees.