Neurobiological data & Husserlian constitution - IV

Publié le

A neural correlate of the noema of the other

At the level of the individual neuron, biological support has been uncovered

for the understanding of the intentional signification of the actions of an other

agent (di Pellegrino et al. 1992; Gallese et al. 1996; Rizzolatti and Gallese

1997). To the extent that an organism is capable of understanding the intentional

signification of its own actions, it acquires the possibility of immediately

understanding the signification of the actions of others, that is, without

the mediation of any perception of an initially non-interpreted bodily movement

followed by a judgement which attributes meaning on the basis of a

special interpretation. In the pre-motor cortex of the macaque monkey (frontal

area 5) a class of “mirror neurons” was found, the characteristic of which

is that they are activated both when the animal accomplishes certain goaldirected

hand movements and when he observes the experimenter in the process

of accomplishing what one is obliged to call the same action. Where the

latter is defined as a series of articulated movements aimed at one and the same

goal no matter what the limb, or muscles of the movements brought into play.

These neurons make up a vocabulary of all the actions necessary for the animal

to bring its food to its mouth: “grasp with the hand,” “grasp with the hand

and the mouth,” “reach,” “catch with precision,” or “with the full hand,” etc.

When another monkey was placed in the presence of the recorded one, a

synchronised firing of the neurons of area 5 was noted each time this other

monkey grasped some food. Trying to establish the existence of mirror-neurons

in humans, it has been discovered that observing the experimenter grasping

an object induced in the human subject an increase in the motor potential

evoked by magnetic stimulation of the cortex in the muscles which bring into

play the execution of the same movement (Fadiga et al. 1995). In both cases,

positron emission tomography shows an activation in Broca’s area, the analog

of monkey’s frontal area 5 known for associating a somatotopic representation

of the hand (predominant with the monkey) and a somatotopic

representation of the mouth (predominant with the human).

What could be the functional role of these mirror-neurons in humans, neurons

whose schema of activation seems capable of representing the identity

between the meaning of one’s own actions and those of the other, but not the

emotional state nor the predisposition of the subject to action? The scientists

speculate that this comprehension of the actions of others lies at the root of

speech (Rizzolatti et al., 1996). We understand each other through language

because, in advance, we have already understood each other’s actions by visual

observation, which is the most basic intersubjective precondition. Without

pressing too far the question of an empirical confirmation of phenomenology,

it must be admitted that these findings justify Husserl’s upholding of the idea

that our empathic experience of the other is an internal imitation of the movement

accomplished by the other. This implies an actualisation of the kinesthetic

sensations corresponding to the movement in question, and not its effective

execution nor even (against Max Scheler) an affective fusion with the other. In

addition, Husserl was also amply justified in holding that the constitution of the

world is intersubjective and practical and not solipsistic and representational.

 

Notes

1. This paper was presented at The Naturalistic Tension: An International Symposium on

Phenomenology and Cognitive Science, University of Tampere, May 16–17, 2002. I

would like to express my appreciation to Dr. Christopher Macann for the English translation,

and to Professor Leila Haaparanta, and the participants at this colloquium for their

friendly reception and interesting comments.

2. Concerning the role of kinesthesia in (late) Husserlian constitution theory, we rely on

Husserl’s manuscripts of the thirties, series B and D, at Archives Husserl de Paris, ENS,

45, rue d’Ulm.

3. Husserl himself expresses his theory of constitution in terms of System (ms D13, 1921).

To the system of appearances of spatial things in perspective whose sense of being we

constitute by moving our eyes, our neck and our whole body there corresponds the system

of postures and movements of our body parts, such as sense organs. This correspondence

is no mere mapping, but a motivating running through of our motor and sensory

organs by our kinesthetic sensations as we orient ourselves in relation to objects. An analogy

in scientific physiology might be the motor or sensory systems, as the physiologist

understand them. With the following reservation: that most neuroscientists, when they

are not uniquely interested in the anatomical structures (receptors, effectors, conduction

paths, cortical maps, etc.), have a piecemeal (“modular”) approach to the functions sustained

by these structures, one that is wholly opposed to the holistic and highly differentiated

approach of Husserl.

4. On experience as a factor of cerebral plasticity cf. Elbert et al. (1995); Mogilner et al.

(1993); Pascual-Leone and Torres (1993); Pascual-Leone, Grafman, and Hallett (1994);

Sterr et al. (1998); Wall, Felleman, and Kaas (1983), and the papers by Merzenich and

collaborators in the references.

 

Publié dans philosophie

Commenter cet article