Corrado Sinigaglia

What is so special about embodied simulation

Simulation theories of social cognition abound in the literature, but it is often unclear what simulation means and how it works. The discovery of mirror neurons, responding both to action execution and observation, suggested an embodied approach to mental simulation. Over the past few years this approach has been hotly debated and alternative accounts have been proposed. We discuss these accounts and argue that they fail to capture the uniqueness of embodied simulation (ES). ES theory provides a unitary account of basic social cognition, demonstrating that people reuse their own mental states or processes represented with a bodily format in functionally attributing them to others.

Motor Cognition and Its Role in the Phylogeny and Ontogeny of Action Understanding.

Social life rests in large part on the capacity to understand the intentions behind the behavior of others. What are the origins of this capacity? How is one to construe its development in ontogenesis? By assuming that action understanding can be explained only in terms of the ability to read the minds of others--that is, to represent mental states--the traditional view claims that a sharp discontinuity occurs in both phylogeny and ontogeny. Over the last few years this view has been challenged by a number of ethological and psychological studies, as well as by several neurophysiological findings. In particular, the functional properties of the mirror neuron system and its direct matching mechanism indicate that action understanding may be primarily based on the motor cognition that underpins ones own capacity to act. This article aims to elaborate and motivate the pivotal role of such motor cognition, providing a biologically plausible and theoretically unitary account for the phylogeny and ontogeny of action understanding and also its impairment, as in the case of autistic spectrum disorder.

Where does an object trigger an action? An investigation about affordances in space

A series of experiments provide evidence that affordances rely not only on the mutual appropriateness of the features of an object and the abilities of an individual, but also on the fact that those features fall within her own reachable space, thus being really ready-to-her-own-hand. We used a spatial alignment effect paradigm and systematically examined this effect when the visually presented object was located either within or outside the peripersonal space of the participants, both from a metric (Experiment 1) and from a functional point of view (Experiment 2). We found that objectual features evoke actions only when the object is presented within the portion of the peripersonal space that is effectively reachable by the participants. Experiments 3 and 4 ruled out that our results could be merely accounted for by differences in the visual salience of the presented objects. Our data suggest that the power of an object to automatically trigger an action is strictly linked to the effective possibility that an individual has to interact with it.

The bodily self as power for action

The aim of our paper is to show that there is a sense of body that is enactive in nature and that enables to capture the most primitive sense of self. We will argue that the body is primarily given to us as source or power for action, i.e., as the variety of motor potentialities that define the horizon of the world in which we live, by populating it with things at hand to which we can be directed and with other bodies we can interact with. We will show that this sense of body as bodily self is, on the one hand, antecedent the distinction between sense of agency and sense of ownership, and, on the other, it enables and refines such distinction, providing a conceptual framework for the coherent interpretation of a variety of behavioral and neuropsychological data. We will conclude by positing that the basic experiences we entertain of our selves as bodily selves are from the very beginning driven by our interactions with other bodies as they are underpinned by the mirror mechanism.

The space of affordances: a TMS study.

Previous studies have shown a motor recruitment during the observation of graspable objects. This recruitment has been considered crucial in encoding the observed objects in terms of one or more potential motor acts. However, an agent can actually act upon an object only when the latter is close enough to be reached. Thus, the question we deal with in this paper is whether the motor system is always activated whenever a graspable object comes into view or whether it requires the object to be located within the reachable space of the perceiver. The left primary motor cortex was magnetically stimulated and motor evoked potentials (MEPs) were recorded while participants observed graspable and non graspable objects located within or outside their own reachable space. We found higher MEPs during the observation of graspable objects falling within the reachable space compared to the observation of either a non graspable object or a graspable object falling outside the reachable space. Our results shed new light on the functional role of the motor system in encoding visually presented objects. Indeed, they clearly indicate that its recruitment is spatially constrained, as it depends on whether the object falls within the actual reaching space of the onlooker.

Understanding Actions of Others: The Electrodynamics of the Left and Right Hemispheres. A High-Density EEG Neuroimaging Study

Background When we observe an individual performing a motor act (e.g. grasping a cup) we get two types of information on the basis of how the motor act is done and the context: what the agent is doing (i.e. grasping) and the intention underlying it (i.e. grasping for drinking). Here we examined the temporal dynamics of the brain activations that follow the observation of a motor act and underlie the observers capacity to understand what the agent is doing and why. Methodology/Principal Findings Volunteers were presented with two-frame video-clips. The first frame (T0) showed an object with or without context; the second frame (T1) showed a hand interacting with the object. The volunteers were instructed to understand the intention of the observed actions while their brain activity was recorded with a high-density 128-channel EEG system. Visual event-related potentials (VEPs) were recorded time-locked with the frame showing the hand-object interaction (T1). The data were analyzed by using electrical neuroimaging, which combines a cluster analysis performed on the group-averaged VEPs with the localization of the cortical sources that give rise to different spatio-temporal states of the global electrical field. Electrical neuroimaging results revealed four major steps: 1) bilateral posterior cortical activations; 2) a strong activation of the left posterior temporal and inferior parietal cortices with almost a complete disappearance of activations in the right hemisphere; 3) a significant increase of the activations of the right temporo-parietal region with simultaneously co-active left hemispheric sources, and 4) a significant global decrease of cortical activity accompanied by the appearance of activation of the orbito-frontal cortex. Conclusions/Significance We conclude that the early striking left hemisphere involvement is due to the activation of a lateralized action-observation/action execution network. The activation of this lateralized network mediates the understanding of the goal of object-directed motor acts (mirror mechanism). The successive right hemisphere activation indicates that this hemisphere plays an important role in understanding the intention of others.

Looking Ahead: Anticipatory Gaze and Motor Ability in Infancy

The present study asks when infants are able to selectively anticipate the goals of observed actions, and how this ability relates to infants’ own abilities to produce those specific actions. Using eye-tracking technology to measure on-line anticipation, 6-, 8- and 10-month-old infants and a control group of adults were tested while observing an adult reach with a whole hand grasp, a precision grasp or a closed fist towards one of two different sized objects. The same infants were also given a comparable action production task. All infants showed proactive gaze to the whole hand grasps, with increased degrees of proactivity in the older groups. Gaze proactivity to the precision grasps, however, was present from 8 months of age. Moreover, the infants’ ability in performing precision grasping strongly predicted their ability in using the actor’s hand shape cues to differentially anticipate the goal of the observed action, even when age was partialled out. The results are discussed in terms of the specificity of action anticipation, and the fine-grained relationship between action production and action perception.

Ready both to your and to my hands: mapping the action space of others.

To date, mutual interaction between action and perception has been investigated mainly by focusing on single individuals. However, we perceive affording objects and acts upon them in a surrounding world inhabited by other perceiving and acting bodies. Thus, the issue arises as to whether our action-oriented object perception might be modulated by the presence of another potential actor. To tackle this issue we used the spatial alignment effect paradigm and systematically examined this effect when a visually presented handled object was located close either to the perceiver or to another individual (a virtual avatar). We found that the spatial alignment effect occurred whenever the object was presented within the reaching space of a potential actor, regardless of whether it was the participants own or the others reaching space. These findings show that objects may afford a suitable motor act when they are ready not only to our own hand but also, and most importantly, to the others hand. Our proposal is that this effect is likely to be due to a mapping of our own and the others reaching space and we posit that such mapping could play a critical role in joining our own and the others action.

Through the looking glass: Self and others

In the present article we discuss the relevance of the mirror mechanism for our sense of self and our sense of others. We argue that, by providing us with an understanding from the inside of actions, the mirror mechanism radically challenges the traditional view of the self and of the others. Indeed, this mechanism not only reveals the common ground on the basis of which we become aware of ourselves as selves distinct from other selves, but also sheds new light on the content of our self and other experience, showing that we primarily experience ourselves and the others in terms of our own and of their motor possibilities respectively.

Grasping affordances with the other’s hand: A TMS study

The power of an object to afford a suitable act has been shown to depend on its reachability. Nevertheless, most of our perception and action occur in a social context. Little research has directly explored whether the possibility for other people to act upon an object may affect our processing of its affording features. To tackle this issue, we magnetically stimulated the left primary motor cortex and recorded motor-evoked potentials (MEPs) while participants were presented with a handled object (i.e. a mug) close either to them or to a virtual individual such as an avatar. We found highest MEPs both when the mug was near enough to be actually reachable for the participants and also when it was out of reach for them, provided that it was ready to the avatars hand. We propose that this effect is likely to be due to an interpersonal bodily space representation, which plays critical role in basic social interaction.