Paul J. M. Jorion

Paul_jorion@email.msn.com

Comments in Behavioral and Brain Sciences

 

Comment on Pulvermueller, F. Words in the brain's language

abstract:

A Hebbian model for speech generation opens a number of paths. A cross-linguistic scheme of functional relationships (inspired by Aristotle) dispenses with distraction by the "parts of speech" distinctions, while bridging the gap between "contents" and "structure" words. A gradient model identifies emotional and rational dynamics and shows speech generation as a process where a speaker's dissatisfaction gets minimised.

 

Thought as word dynamics (1998)

Pulvermüller's paper communicates the power of a Hebbian approach to word dynamics. Firstly, it accounts in an associationist manner for clause generation, where a speaking subject's prior history provides the template for later connections between concepts. Secondly, through the mechanism of weighted activation, a distinctive light is shed on signification. Indeed, in contrast with the classical view where the overall meaning of a clause results from serial processing of the words composing it, within the Hebbian framework the meaning of a sentence is a global three-dimensional packet of intermixing atomic meanings as provided by words (the concept is reminiscent of the scholastic notion of the complexe significabile where words combined evoke a "state of affairs" - see Jorion 1997b). Such an approach is close to what the semantics of languages such as Chinese force on the linguist and underlines how often our current reflections derive from familiarity with a single Indo-European language.

Pulvermüller revives the "subsumptive" (see Hogan 1998) approach to language of Aristotle. With the Greek philosopher, in steps of increased semantic significance, concepts are first associated in pairs (to constitute atomic, then molecular propositions), are then composed into reasoning (of a syllogistic nature), and finally concatenated into full-blown discourse (see Jorion 1996). Within Aristotle's approach, our modern distinction of "parts of speech" is cosmetic and of no functional consequence.

Pulvermüller's elementary dichotomy of "concrete" and "abstract" can be usefully bridged by distinguishing a set of functional relationships with cross-linguistic validity. These cover firstly, relations between words and the empirical world, secondly, between the words themselves, and thirdly, between the universe of words and the person of the speaking subject. Here for a brief exposition of such Aristotelian functions:

1) the monstrative such as in "this...", "I..." (Jakobson's shifters), establishing a direct relationship between words and things of the empirical world,

2) the anaphoric, relating one or more words to one or several others, previously uttered: "which...", "as mentioned before...", "whatchamacallit", etc.,

3) the categorematic, i.e., the universal collectives, "mammals", "people of a friendly disposition", which abstract collections of the empirical world into concepts,

4) the determinants (our adjectives, verbs, adverbs) - encompassing the Chinese "modifiers" ("white", "in Santa Monica") and markers of belonging ("the boat's...", "her"), restricting universals to one or more specific instances,

5) the syncategorematic: being the copula, the associative connectors and quantifiers of the logician's atomic proposition ("... are ...", "some...") or compatibility modulators ("despite", "meanwhile, back in the forest ..."),

6) the continuity markers ("some time before", "then"), a separate function attempting to grasp our awkward intuition of time,

7) the highlighters, used for stressing parts of our speech ("clearly", "See what I mean?", "jolly", "bloody",

8) the adhesion markers, ("I am certain that...", "I can't visualise that..."), allowing the speaker to specify a degree of personal commitment to his/her own utterances (ranging from the non-committal quotation, "Someone told me about Jesus", to the assertion of identification, "I believe in Jesus") (see on this Jorion 1990: chapter 21; also Jorion 1996).

In addition to the Hebbian "correlational" logic ruling the connections between contents words, Pulvermüller suggests the presence of a second neural mechanism ( 3.3.1), de-linking this time structure words from the might of repeated co-occurrence. Together, these two constitute the required infrastructure for the functional approach delineated above.

Interestingly, the Hebbian perspective achieves per se a synthesis between rational and emotional dynamics habitually seen as divergent principles of discourse generation. I have shown (Jorion 1994) that a subject, its history stored as memory, and an environment, constitute together a single possibility space where behaviour constantly aims at minimising a dissatisfaction level. A framework for behaviour is thus provided, replacing final causes (targets) by efficient causes in a gradient model where intentions (and worries) constitute potential wells. The gradient model applies to speech just as to any type of behaviour. Indeed, a word is a memory trace like that potentially generated by every percept; it is associated - in each of its possible uses - with an affect value. The emotional dynamic of speech production follows a gradient leading to the satisfaction of the speaker. External circumstances - such as the words of an interlocutor in a dialogue situation where several dynamics interact - or inner circumstances - such as one's own moods and feelings - fuel such a continuing process that only death can interrupt (Jorion 1997a).

Thus is vindicated a line of approach first sketched by both the German positivists and the American pragmatists: rationality developed for the species as an adaptive way to safeguard itself, and the individual exercise of rationality contributes at relieving emotional stress. With ANELLA (Associative Network with Emergent Logical and Learning Abilities), I attempted to show how the utterance of sentences materialises, out of necessity, a coarsely syllogistic mode of reasoning, while at the same time bringing appeasement in the speaker (Jorion 1989).

Reference:

Hogan, James P. (1997) Mind Matters. Exploring the World of Artificial Intelligence, New York: Del Rey (Ballantine),

Jorion, Paul, (1989) An alternative neural network representation for conceptual knowledge, Paper presented at the British TELECOM, CONNEX Conference, Martlesham Heath, January 1990, 23 pp, http://cogprints.soton.ac.uk/abs/comp/199806036

Jorion, Paul (1990) Principes des systèmes intelligents, Collection "Sciences cognitives", Paris: Masson; summary in English: http://cogprints.soton.ac.uk/abs/comp/199806039

Jorion, Paul (1994), L'intelligence artificielle au confluent des neurosciences et de l'informatique, Lekton, vol IV, 1994, N2: 85-114; http://cogprints.soton.ac.uk/abs/comp/199807008

Jorion, Paul (1996) La linguistique d'Aristote, in V. Rialle & D. Fisette (eds.), Penser l'esprit: Des sciences de la cognition à une philosophie cognitive, Grenoble: Presses Universitaires de Grenoble: 261-287; http://cogprints.soton.ac.uk/abs/phil/199807012

Jorion, Paul (1997a) Ce qui fait encore cruellement défaut à l'Intelligence artificielle, Informations In Cognito, No 7: 1-4; http://cogprints.soton.ac.uk/abs/comp/199807007

Jorion, Paul (1997b) Jean Pouillon et le mystère de la chambre chinoise, L'Homme, 143: 91-99; http://cogprints.soton.ac.uk/abs/phil/199807013