Page 207 - Deep Learning

190 Adaptation

reflex with the feedback circle as the key building block of human cogni-
37
tion received much attention in the 1950s and 1960s. Unfortunately, Wiener
focused on continuous feedback, which is more relevant for sensorimotor
than cognitive skills and which can only be analyzed with the help of complex
mathematics. These and other factors reduced the influence of the cybernetic
approach. 38
Cybernetics was overtaken by the digital approach, variously called com-
plex information processing and, eventually, artificial intelligence, launched by
A. newell, J. C. Shaw and H. A. Simon with a 1958 article describing the Logic
Theorist, the first symbol-processing computer program that performed a
task, logical deduction, that is recognized as requiring intelligence when done
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by people. The program formalized the notion of heuristic search, an endur-
ing concept. Significantly, the article was published in Psychological Review
rather than in an engineering journal, and the authors offered speculations
on the relation between their program and human cognition. The article thus
simultaneously initiated the field of artificial intelligence and introduced psy-
chologists to computer simulation as a theoretical tool.
paradoxically, the success of the digital symbol manipulating approach
had a detrimental effect on the study of learning. in the period 1958–1979, no
leading cognitive psychologist conducted basic research on the effects of prac-
tice or other problems related to the acquisition of complex cognitive skills.
Success in simulating human behavior – any behavior – was recognized as an
achievement in and of itself, even if a model did not simulate changes in that
behavior over time.
progress toward understanding skill acquisition was instead driven by the
goal of contributing to education and training. Educational psychologists like
david Ausubel and Robert Gagné developed the educational implications of
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the concepts developed in basic research on learning. in his 1965 book The
Conditions of Learning, Gagné summarized research up to that time in a mul-
timechanism theory that specified eight different modes of learning, includ-
ing motor and verbal chaining of actions, two types of discrimination, concept
learning and learning by saving the results of successful problem solving. He also
argued for the importance of specifying the triggering conditions for the different
modes of learning. Focusing on training rather than academic learning, applied
psychologists like paul M. Fitts and Alan t. Welford continued to accumulate
empirical data on the learning of complex skills. in the 1960s, Fitts developed the
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notion of a small number of phases that are characterized by the types of changes
occurring, another enduring contribution. The distinction between sensorimotor
and cognitive skills was not emphasized in this line of work.