Page 129 - Deep Learning

112 Creativity

If the problem solver persists in the face of failure, the activation levels of
the above-threshold options will gradually approach the threshold, and the
below-threshold options will rise correspondingly. Eventually, one or more of
the previously dormant or unheeded options available in some processing unit
will rise above threshold and pass information and activation along to the next
layer. The change at that processing unit is propagated onto the next layer of
processing, which in turn will alter the processing at that layer; and so on.
As the wave of changes propagates from layer to layer, different outcomes
are possible. The change might be dampened. That is, the alteration at layer
N might have little impact on layer N+1 and the change might eventually
fade without causing a change in the top layer, that is, in the person’s prob-
lem representation. On the other hand, the change might be amplified as it
passes from layer to layer, ultimately affecting the problem representation and
possibly direct the problem-solving effort down a novel path. The subjective
experience that accompanies such an event is likely to include relief at being
freed from the impasse and a corresponding enthusiasm for exploring the new
option (wait a minute, I can do this …). Which outcome will occur in any one
situation is massively contingent on the exact structure of the person’s knowl-
edge network and the exact strengths and activation layers as determined by
prior experience.
If a representational change is ultimately triggered by a change in a sin-
gle processing unit, why is the change holistic in character? Why do problem
representations not change the way a digital screen picture would change
if a single pixel were changed? Within each layer, the mutual excitation-
inhibition links between the units in that layer keep the different parts of
the interpretation consistent with each other. As the wave of changes travels
upward, it is subject to integrative and synthesizing processing within each
layer. The result is that, as the Gestalt psychologists insisted, the entire prob-
lem representation undergoes change. Each part is reinterpreted or under-
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stood differently; furthermore, each part is reinterpreted in such a way that
the parts fit together in a coherent, qualitatively different whole. Reversible
figures such as the Necker cube provide a model: When the Necker cube flips
for the observer, each part of the figure – each corner, edge and side – is rein-
terpreted and the parts are all interpreted in such a way that they fit together
and make up a coherent perception of the cube. The holistic nature of the
change is, in part, why a representational change can be subjectively striking
to the person to whom it happens.
Once the representation in working memory has been revised, addi-
tional changes follow. The elements of the new representation serve as new