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G. Riva, M.T. Anguera, B.K. Wiederhold and F. Mantovani (Eds.)
From Communication to Presence: Cognition, Emotions and Culture towards the
Ultimate Communicative Experience. Festschrift in honor of Luigi Anolli
IOS Press, Amsterdam, 2006, (c) All rights reserved - http://www.emergingcommunication.com
Theory of Event Coding - is the outcome of a long series of experiments of single-
neuron recordings in the premotor cortex of behaving monkeys [48, 49]. In
particular, Rizzolatti and colleagues discovered that a functional cluster of premotor
neurons (F5ab-AIP) contains “canonical neurons”, a class of neurons that are
selectively activated by the presentation of an object in function of its shape, size,
and spatial orientation [50-52]. Specifically, these neurons fire during the
observation of objects whose features - such as size and shape - are strictly related to
the type of action that the very same neurons motorically code.
Further, the canonical neurons are activated not only observing the same object,
but also observing a group of objects that have the same characteristics, in terms of
the type of interaction they allow.
Two aspects of these neurons are important [25, 53]. On one side, what correlates
to their discharge is not simply a movement (e.g. opening the mouth), but an action,
that is, a movement executed to achieve a purpose (e.g. tear apart an object, bring it
to the mouth). Second, the critical feature for the discharge is the purpose of the
action, and not some dynamic details defining it, like force, or movement direction.
In a different cluster (F4-VIP) Rizzolatti and colleagues [50, 54] identified a class
of neurons that are selectively activated when the monkey heard or saw stimuli being
moved in its peri-personal space. The same neurons discharge when the monkey
turns its head toward a given location in peri-personal space.
A possibility to explain the dual activation is that these neurons simulate the action
(head-turning) in presence of a possible target of action seen or heard at the same
location [25]:
“We maintain that what integrates these sensory modalities is action simulation.
Because sound and action are parts of an integrated system, the sight of an object at
a given location, or the sound it produces, automatically triggers a “plan” for a
specific action directed toward that location. What is a “plan” to act? We claim that
it is a simulated potential action.” (p. 460).
The existence of these functional clusters of neurons suggests, as predicted by
Heidegger, that a constitutive part of the representation of an object is the type of
interaction that is established with the object itself (readiness-to-hand). In other
words, different objects can be represented in function of the same type of interaction
allowed by them. As underlined by Gallese [47]:
“If this interpretation is correct, objects are not merely identified and recognized by
virtue of their physical ‘appearance’, but in relation to the effects of the interaction
with an agent. In such a context, the object acquires a meaningful value by means of
its dynamic relation with the agent of this relation. This dynamic relation is multiple,
as multiple are the ways in which we can interact with the world by acting within it.
The object-representation ceases to exist by itself. The object phenomenally exists to
the extent it represents the target of an action.” (p.31).
These experimental data match well with the Converged Zone Theory proposed by
Damasio [55]. This theory has two main claims. First, when a physical entity is
experienced, it activates feature detectors in the relevant sensory-motor areas. During
visual processing of an apple, for example, neurons fire for edges and planar
surfaces, whereas others fire for color, configural properties, and movement. Similar