Connectionism / Parallel Distributed Processing (PDP) / Neural Networks: a few milestones backward in time, showing that "new" is relative. (Note that page references are currently listed only for the FIFTH edition of Hergenhahn's An Introduction To The History Of Psychology, though the references are easily identifiable from the index of the sixth edition.)
David Rumelhart and James McClelland
(1986): Connectionism re-emerges in a more
complex form and becomes psychology's dominant
model of the mind, with parallel processing by many
simple neuron-like units instead of the serial
step-by-step following of programmed instructions
(as implied by traditional artifical intelligence
and cognitive science research). (p. 584)
Marvin Minsky and Seymour Papert (1969):
Connectionism in the form of "perceptrons" was
mathematically demolished as a possible model of
the working of the mind. (pp. 583-584)
Frank Rosenblatt (1958): The
"perceptron" was proposed as a model of the mind
based on the architecture of the brain, with an
"input" and an "output" set of simple neuron-like
units, whose interconnections determine the output
(or result of processing) for a given input. (p. 583)
Donald Hebb (1949): proposed that the
connection between two neurons is strengthened when
they become active at the same time -- the basis of
the Hebb Rule which is still the fundamental
mechanism for learning in connectionist
networks. (pp. 581-582, 559-560)
Warren McCulloch and Walter Pitts
(1943): noted that some features of networks of
neurons in the brain -- their arrangements of
excitatory and inhibitory connections -- could be
the basis of computation and mental processing (p. 582)
Edwin Guthrie (1935): argued that the
"stimulus" of behavioral psychology is actually a
practically infinite multitude of micro-stimuli,
representing every possible sensation and bodily
state impinging on an organism at a given moment --
thus implying for future theorists that an "input"
actually consists of a pattern of a vast number of
detectable but unspecifiable inputs, just as
connectionism will eventually make use of.
Edward Thorndike (1898): coined the term
"connectionism" to describe his theory in which
associationism is first applied to behavior in
terms of connections between stimuli and responses,
instead of associations among ideas in the
mind. The "connections" he literally had in mind were
between stimulus and response centers in the brain. (p. 343)
David Hartley (1749): related sensations
to physical vibrations in the nervous system,
giving a material basis to the associaton of ideas
and claiming that associations were formed when
such vibrations occurred at the same time (thus
anticipating the Hebb rule by 200 years). (p. 136)
David Hume (1748/1739): claimed that the
mind itself was an unnecessary element of theories
of mental life, since if sensations and ideas acted
in accord with some simple laws of association
(such as resemblance and contiguity), they would
combine in such a way as to build our concepts and
thoughts without some other entity like "the mind"
having to play a role (i.e., the ideas would think
for themselves!); this anticipated the neural
network theorist's goal of computing using simple
rules for modulating connections among simple
units, instead of using explicit sets of program
instructions. (pp. 132, 133-134)
Aristotle (c. 350 BC): conceived of
associations among ideas (based on their
simliarity, contrast, and contiguity) as the basis
of all complex thought, thus setting the terms of
the whole psychological enterprise for the next
2300 years (and counting...) (p. 49)