Tone of Voice and Mind : The Connections between Intonation ...

A bilateral neural network simulation 231
tivation will, however, contribute to the affective “mood” and specifically the
subjective consciousness of the system with, for example, indirect effects on
subsequent processing of sensory information.
The entire simulation system
As illustrated in Figure 8-1, for each of the ten sensory maps (where the feature
topology emerges), there is a verbal map (where labels are given), an association
map (where cerebral asymmetries via callosal inhibition are introduced),
and a frontal map (where the relative strength of hemispheric activation is
computed and object recognition occurs). The system as a whole is engaged
in a cycle of activities – sensory perception, verbal-labeling, associative manipulation,
and frontal summation for determining motor behavior. When the
threshold for motor behavior is not exceeded, the system returns to a sensory
level to await further stimulation and begin another cycle (Figure 8-10). Since
competing tasks have not been implemented, the singularity of mind in the
simulation refers only to the fact that activation of all cortical maps is limited to
one region (focus or fringe). In a more complex simulation in which the mechanisms
of neuronal synchronization have been implemented, the agent would
be capable of multiple tasks and a competitive interaction among tasks would
bring about a switching from one task to another at the completion of any
sensory-verbal-associative-frontal cycle. Depending on the biological salience
of competing tasks, the focus of attention would then persist as long as the
synchronization of one neuronal subsystem involves more neurons than other
subsystems. The essential idea behind the bilateral architecture is that, unlike
a “unilateral brain,” a “bilateral brain” has a principled method by which the
“limited capacity” of LH focal attention can be increased, but without introducing
conflicting, competing or simply irrelevant information. For the object
recognition task, when the fit between external stimulus and previously
learned features is close, there is no difficulty for the stand-alone LH to undertake
motor behavior; in such a case, the LH finds the correct label for the
stimulus, regardless of the presence or absence of fringe information. When
the fit isnotexact,however– as is normally the case in a real-world situation,
interhemispheric communication leads to “contextual” fringe activity which
can influence the focal activity of the motor dominant LH. The relative activation
of the nucleus and fringe indicates whether or not the “best-fit” in the LH
should be relied upon for motor behavior. If the RH activation is supportive,
the RH serves to guide the LH in its motor output. If it is not supportive, the