Competing "retrieval" rule vs compiled "habit" rule?

[danilo_fum]

Dear Richard and dear ACTers:

here are our two (Euro) cents of thoughts concerning the bread-errand task
and related debate.  In fact, we filled a whole coffee break discussing
this problem; in evaluating our reply, however, please note that we drank
Espresso.

According to our point of view, to fully grasp (and model) the bread errand
task it is necessary to:

1.  Get an adequate understanding of how people drive home following a
known route.  This probably has to do, as many of you pointed out, with the
employment of perceptual cues (affordances) that activate motor programs.

2.  Get an adequate understanding of the role of situated cognition in
perspective memory tasks.  A good starting point could be represented by
Erik's proposal, in which the perceptual cue triggers the retrieval of a
suspended intention (analogously to what happens in the Patalano & Seifert
model).  In our case, the specific goal "stop at the bread shop" could have
been associated with the bread shop sign.  A set of "perspective" productions
(maybe a general retrieval mechanism?)  could retrieve the suspended
intention after being triggered by the perceptual cue, provided that it
is able to win the competition with the other productions related with the
driving and conversation tasks.

It is also possible to hypothesize that, in this and similar situations, an
explicit set of "rehearsal" productions could be used to increase the
activation level of an intention, and to make its retrieval more likely.
This could be similar to what happens in the WM phonological loop, or in
the strengthening mechanism of Altmann and Trafton TOH model.

Mike raised an interesting issue concerning the retrieval costs in strategy
selection.  There is some evidence (Rickard, 1997) for the view that if two
strategies compete for the choice of the next problem solving operator, one
being based on the explicit retrieval of previous instances and the other
relying on a procedural mechanism, only one of them could be used due to
attentional limitations.  Data from a new experiment we carried out with
the toads-and-frogs puzzle (paper submitted at the CogScie conference) seem
to support this point, too.

Any way, the retrieval cost issue is deeply related with the new
buffer-oriented architecture.  Maybe it could be untangled only by fully
understanding the ontological status of the buffers themselves
(psychological structures, computational devices, neural-based constructs?)

We eagerly look forward to learn something more at the next ACT-R workshop.


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Fabio Del Missier
Danilo Fum
Andrea Stocco

Department of Psychology
University of Trieste
via S.Anastasio, 12
I - 34134 Trieste
Italy

e-mail: {delsmisfa,fum,stocco}@univ.trieste.it
Phone: +39 040 676-2708
Fax:   +39 040 676-2757
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