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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
patterns of activation in feature maps on other modalities represent how the entity
might sound and feel, and also the actions performed on it.
Second, when a pattern becomes active in a feature system, clusters of conjunctive
neurons (convergence zones) in association areas capture the pattern for later
cognitive use. As shown also by the data collected by Rizzolatti, cluster of
conjunctive neurons codes the pattern, with each individual neuron participating in
the coding of many different patterns.
Damasio assumes the existence of different convergence zones at multiple
hierarchical levels, ranging from posterior to anterior in the brain. At a lower level,
convergence zones near the visual system capture patterns there, whereas
convergence zones near the auditory system capture patterns there. Further,
downstream, higher-level association areas in more anterior areas, such as the
temporal and frontal lobes conjoin patterns of activation across modalities.
A critical feature of convergence zones underlined by Simmons and Barsalou is
modality-specific re-enactments [56, 57]: once a convergence zone captures a feature
pattern, the zone can later activate the pattern in the absence of bottom-up
stimulation. In particular, the conjunctive neurons play the important role of
reactivating patterns (re-enactment) in feature maps during imagery, conceptual
processing, and other cognitive tasks. For instance, when retrieving the memory of
an apple, conjunctive neurons partially reactivate the visual state active during its
earlier perception. Similarly, when retrieving an action performed on the apple,
conjunctive neurons partially reactivate the motor state that produced it. This process
has two main features:
- It is similar, but never constitutes a complete reinstatement of the original
modality-specific state: even if some semblance of the original state is
reactivated, a re-enactment is always partial and potentially inaccurate.
- It is not necessarily conscious: Although conscious re-enactment is viewed
widely as the process that underlies mental imagery, re-enactments need not
always reach awareness.
The process of re-enactment is at the core of the Situated Simulation Theory
proposed by Barsalou [56]. For this author, conceptual representations are
contextualized and dynamical multimodal simulations (re-enactments) distributed
across modality-specific systems. As suggested by Barsalou [56]:
“A concept is not a single abstracted representation for a category but is instead a
skill for constructing idiosyncratic representations tailored to the current needs of a
situated action... More than the focal category is represented in a given simulation.
Additional information as background settings, goal directed actions and
introspective states are also typically included in these simulations, making them
highly contextualized.” (p. 521).
According to this view, a fully functional conceptual system can be built on
reenactment mechanisms. As shown by Barsalou and his group [56, 58, 59] using
these mechanisms, it is possible to implement the type-token distinction, categorical
inference, productivity, propositions, and abstract concepts.
The Situated Simulation Theory fits well with the Common Coding Theory: first,
modality-specific sensorimotor areas become activated by the perceptual input (an
apple) producing patterns of activation in feature maps; then, clusters of conjunctive