D. O. HEBB
Donald Olding Hebb (1904–1985) became intrigued with psychology through the writings
of Sigmund Freud (p. 258), which convinced him there was room for a more rigorous ap-
proach. This insight came while spending some nine years teaching school in Quebec fol-
lowing his graduation from Dalhousie University in 1925. Curious about psychology
Hebb arranged to attend McGill University as a part-time student, and was introduced to
the more precise methods of Ivan Pavlov (p. 178) by Boris P. Babkin and Leonid Andreyev.
Hebb went on to work with two brain pioneers: Karl S. Lashley and Wilder Penfield. He
worked with Lashley at Harvard, receiving his Ph.D. in 1936, and again in 1942 when
Lashley was appointed director of the Yerkes Laboratory of Primate Biology in Orange Park,
Florida. During the intervening years, Hebb enjoyed a fellowship at the Montreal Neuro-
logical Institute with Penfield and taught at Queens University in Ontario. He took all his
teaching responsibilities seriously, from his days as an elementary school principal and
high school teacher to the training of graduate students at McGill, where he returned as a
professor in 1946. His approach was unique—he sent misbehaving elementary school
children out to play and had graduate students audit courses, rather taking them for cred-
it—each mechanism designed to develop and motivate better learning.
A NEUROPSYCHOLOGICAL THEORY
GROWTH OF THE ASSEMBLY
This chapter and the next develop a schema of neural action to show how a rapprochement can be made between (1) perceptual generalization, (2) the permanence of learning, and (3) attention, determining tendency, or the like. It is proposed first that a repeated stimulation of specific receptors will lead slowly to the formation of an “assembly” of association-area cells which can act briefly as a closed system after stimulation has ceased; this prolongs the time during which the structural changes of learning can occur and constitutes the simplest instance of a representative process (image or idea). The way in which this cell-assembly might be established, and its characteristics, are the subject matter of the present chapter. In the following chapter the interrelationships between cell-assemblies are dealt with; these are the basis of temporal organization in central processes (attention, attitude, thought, and so on). The two chapters (4 and 5) construct the conceptual tools with which, in the following chapters, the problems of behavior are to be attacked.
The first step in this neural schematizing is a bald assumption about the structural changes that make lasting memory possible. The assumption has repeatedly been made before, in one way or another, and repeatedly found unsatisfactory by the critics of learning theory. I believe it is still necessary. As a result, I must show that in another context, of added anatomical and physiological knowledge, it becomes more defensible and more fertile than in the past.
The assumption, in brief, is that a growth process accompanying synaptic activity makes the synapse more
From D. O. Hebb, “The First Stage of Perception: Growth of the Assembly.” In The Organization of Behavior: A Neuropsycho-
logical Theory (pp. 60–79). New York: John Wiley & Sons, 1949.