Brains, Persons, and Society *** ABSTRACTS    Cervelli, Persone e Società ***ABSTRACTS

Sergio Levi
Università degli Studi di Milano

Agentive Competence: towards a Mirror Account of Action Understanding?

 About ten years ago the discovery of mirror neuron (MN) systems in both human and nonhuman primates (Rizzolatti et al. 1996; Gallese et al. 1996) initiated a revolution in our philosophical views of the relations between perception and action. The particularity of MNs is that they are activated during the performance of transitive actions (such as grasping, holding, bringing something to the mouth) as well as during the observation of other individuals performing the same or similar actions. Actions performed and perceived are said to be ‘broadly’ or ‘strictly’ congruent depending on the similarity of goals, objects, movements (Rizzolatti and Sinigaglia 2006). What this revolution seems to highlight is the centrality of action for social understanding. One of the most debated problems, however, is whether MNs have simply a triggering and preparatory function towards action or if they also play a role in the recognition and understanding of the actions and emotions of other individuals. According to a common view (cf. Rizzolatti and Arbib 1998; Gallese and Goldman 1998; Gallese 2005) MNs help an observer to understand the actions of other individuals by allowing her to form a “motor representation” that simulates the performance of a similar action on the part of the observer. Much like the imitation ability in human infants this mature simulation capacity could provide the basis (on this view) for social understanding and possibly for cooperative joint action (Pacherie and Dokic 2004). It is generally left to discussion whether such “representations” are to be construed as agent-neutral representations (of impersonal events) or rather as instances of mindreading that ascribe intentions and mental states to agents.

The aim of the paper is to investigate the role of MNs in the recognition and mutual understanding of actions in both human and nonhuman social interaction. It is a common view that a motor account of social cognition and communication rests far beyond the reach of our scientific data and theoretical needs. I think however that a mirror account of action understanding is a realistic and viable project whose success will depend on the clarity of our conceptual framework. I concentrate my attention on the relation between the dual role (performance/detection) of MNs and the conditions for mutual action understanding. To bridge the gap between motor competence (based on MNs and other canonical motor neurons) and action understanding (be it understood as triggering, simulating or even internally mimicking) I propose an account of the “minimal units” of our agentive competence based on the technical notion of an action repertoire.

The “action repertoire” of an individual is defined as the system of all and only actions (types) the individual is able to perform and can be said to be competent on. An individual can recognize that a particular action is being performed (by an individual other than him) only if the action is of a kind which belongs in her action repertoire. A system indeed is not a bare set of items: it is what shapes our experience by determining the possible contents of our expectations. The action repertoire is therefore the framework within which all understanding and expectation can take place.

In order to prove that the ultimate constituents of our agentive competence are overt actions an argument is needed to block reduction of genuine actions into sub-parts such as internal tryings (as in Hornsby 1980 and Pietroski 1998) or peripheral moves (as in Davidson 1987). My argument hinges on the notion of phase-sensitivity. We know that some mirror neurons are “phase-sensitive” in the sense that they are differently activated during the various temporal phases of the action observed. This phase-sensitivity, however, in no way undermines the unity represented by the action, say, of grasping a cup as a whole. Action phases, in other words, are never taken to be actions or sub-actions in their right: they cannot be segregated without ceasing to make a “sense” to the observer and the agent as well. I claim that phases of actions are not actions by any point of view. What they lack is precisely the unity which goals confer on genuine actions. What the study of MN systems reveals is rather that phase-sensitivity conspires with our “action repertoire” to produce expectations that are sufficiently determinate and generally correct. I then propose that the notion of a sub-personal “action repertoire” (constituted of “minimal units” corresponding to action types) could provide an answer to many other problems in the MN research program.

A final suggestion concerns intentionality. Philosophers like Dennett maintain that the fact that an action is said to be intentional is more a judgment in the eye of the interpreter than a real “aspect” of the action itself. Recent studies on MN systems seem to mandate a positive interpretation of this asymmetry. When we describe the MN system of an agent (which is obviously different from assuming her point of view) the distinction between performing a certain action and intentionally performing the action blurs. On the other hand it may be a property of MNs that of prompting the observer to view the individual performing the action more as a genuine agent than a simple participant or a Dowtian proto-Agent (cf. Dowty 1991). If this is true, then the view that MN systems yield “agent-neutral representations” of actions and accomplishments will require some revision.