Thursday, January 24, 2008

The Cognitive Foundations of Perspective II

So in my last post I summarized a bunch of overlapping scientific research programs which can be combined under the notion of mental representation as a creation of a virtual “systemic space”, which can be is exemplified by the idea of short-time memory as a “workbench”, where you can store and manipulate virtual objects, which is used frequently in the cognitive sciences.

Quite strikingkly, when we use Wittgenstein’s (1953) notion of shared activities as ‘games’ and the creation of a shared systemic space as a ‘language game’, there are also some interesting implication of Pinker et al.’s (2008) statement that language serves as a as a
“reference point in coordination games.” (Pinker et al. 2008).
Thus we can also locate their definition of “focal point” i.e.,
"a salient location that two rational agents can agree on when they would be better off coordinating their behavior than acting independently.” (Pinker et al. 2008: 837)
on Bühler’s coordinate system of subjective orientation, or our notion of a shared systemic space.
On this view we can regard a discourse as the negation of the exact focal position of a proposition in the coordinate system of the shared systemic space, (what Pinker et al. call the ‘problem space’). According to Pinker et al., such negotiation is mostly used
“to negotiate the type of relationship holding between speaker and hearer (in particular, dominance, communality, or reciprocity)” (Pinker et al. 2008: 833)
Hurford (2007) reviews further approaches which can be subsumed under this notion:
The first he mentions is Discourse Representation Theory (DRT: Kamp and Reyle 1993). DRT is concerned with describing from a semantic point of view how in discourse we build up a universe consisting of the things we mention. In Kamp and Reyle’s notation this ‘discourse universe’ is represented by a box, which they call a Discourse Representation Structure. The most simple kind of structure in such a DRS would look something like this, with the set of ‘discourse referents’ (x, y, z, etc.) at the top of the box:

This, of course, is basically what I, following Köller (2004), would call a systemic space.
According to Kamp and Reyle, the process of semantic representation is the following: On hearing a sentence (S1), we create a DRS. When the next sentence (S2) is uttered in discourse, this sentence contributes new information to the already constructed DRS, or in my notation, new propositions are transferred into the systemic space or old ones are transformed. This process goes on and on with every new sentence.
Thus, the hearer relates the new sentence to the informational structure already obtained, thereby dynamically construing and manipulating the shared systemic space. (Kamp & Reyle 1993: 59). We could say that with every sentence we change from one mental model of the discourse to another (i.e. M1 ->M2 ->M3, etc.) (Kamp & Reyle 1993: 96).
Kamp & Reyle also have something very interesting to say about the cognitive and attentional underpinnings of the representation of shared systemic spaces: When you hear a proper name in discourse, you assign it an index (like x, y, z, etc.) to make temporary reference possible and to keep track of the discourse referent. They call this an ‘external anchor’ for a discourse referent (x) which maps x onto some real individual (like say, Zombie-Scientist George if he really existed) (Kamp & Reyle 1993: 248)

This proposal is closely related to some other theories of cognition. According to Zenon Pylyshyn’s theory of FINST, regarding the ability to keep track of moving objects in a visual scene,
“a small number of visual objects can be preattentively indexed or tagged and thereby accessed more rapidly by a subsequent attentional process (e.g., the traditional "spotlight of attention") (Sears & Pylyshyn 2000: 1)
These visual indices can be seen as mental labels that can be attached to objects in order to keep track of them. (Hurford 2007: 92).

Another related theory, highlighted by Hurford (2007: 139), is ‘File Change Semantics”, according to which
“A listener’s task of understanding what is being said in the course of a conversation bears relevant similarities to a file clerk’s task. Speaking metaphorically, let me say that to understand an utterance is to keep a file which, at every time in the course of the utterance, contains the information that has so far been conveyed by the utterance.” (Heim, 1983:167)
Again, there is a psychological theory which closely echoes this assessment in the visual domain. According to Kahneman & Treisman (1992) set up ‘object files’
“as a temporary episodic representation, within which successive states of an object are linked and integrated” (Kahneman & Treisman 1992: 175)
These files are constantly updated by new information about the target’s features or location.
The attentional limit of things we can consciously be aware of seems to lie at 4 target objects, (Hurford 2007: 93, Cowan 2001) and seems to hold true for the perceptual space as well as for the systemic space.

This research about visual indexes as
“a means of setting attentional priorities when multiple stimuli compete for attention” (Sears and Pylyshyn 2000: 2) )
,as well as the idea of information ‘files’ goes very well with our notion of language as a means to pilot attention toward certain propositions in the systemic space.

In sum, we see that there are overlapping theories concerning mental representations of the perceptual space as of the virtual systemic space. Hurford (2007) argues that this independent convergence of several areas of research indicates that:
“one bit of language-processing machinery has been co-opted (and probably adapted somewhat) from pre-existing visual scene processing machinery.” (Hurford 2007: 140)

References:


Cowan, Nelson. 2000. The magical number 4 in short-term memory: A reconsideration of mental storage capacity. Behavioral and Brain Sciences 24(1), 87–114.

Heim, Irene. 1983. File change semantics and the familiarity theory of definiteness. In R. Bäuerle, C. Schwarze, and A. von Stechow (Eds.), Meaning, Use, and Interpretation of Language. Berlin: Walter de Gruyter: 164– 189.

Hurford, James M. 2007. The Origins of Meaning: Language in the Light of Evolution. Oxford: OUP.

Kahneman, Daniel. and Anne. Treisman.1992. The reviewing of object files: object-specific integration of information. Cognitive Psychology 24, 175–219.

Kamp, Hans and Uwe Reyle. 1993. From Discourse to Logic: Introduction to Modeltheoretic Semantics of Natural Language, Formal Logic and Discourse Representation Theory. Dordrecht, Holland: Kluwer Academic.

Köller, Wilhelm. 2004. Perspektivität und Sprache. Zur Struktur von Objektivierungsformen in Bildern, im Denken und in der Sprache. Berlin/ New York: de Gruyter.

Pinker, Steven, Martin A. Nowak and James L. Lee. 2008. The logic of indirect speech. Proceedings of the National Academy of Sciences 105.3: 833–838.

Sears, Christopher R. and Zenon W. Pylyshyn. 2000. “Multiple object tracking and attentional processing.” Canadian Journal of Experimental Psychology 54(1), 1–14.

Wittgenstein, Ludwig. 1953. Philosophical Investigations. Oxford: Basil Blackwell. (Translated by G. E. M. Anscombe)

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