Skinner, B. F. (1981). Pavlov’s influence on psychology in America

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Journal OJ rhr History OJ the Behavioral Scicncn 
17 (1981): 242-245. 
PAVLOV’S INFLUENCE ON PSYCHOLOGY IN AMERICA 
B. F. SKINNER 
It is hard to think of oneself as a contemporary of a man who died forty-four years 
ago, but it is nonetheless true that on two occasions Pavlov and I worked on the same 
problem at the same time. I mention this for what it may be worth in supporting my right 
to comment on Pavlov’s contribution to psychology. I am not an authority on Pavlov, 
and I shall report here little more than what I learned about his research as a student and 
then as it affected my own work and those of whom I remained a contemporary for a 
much longer period of time. 
That American psychologists learned about Pavlov through German publications is 
clear from the fact that they first spelled his name with w’s instead of v’s. In 1909 R. M. 
Yerkes and S. Morgulis published “The Method of Pawlow in Animal Psychology.”l 
Neither author seems to have been much influenced by Pavlov’s work, but John B. Wat- 
son was different, and fortunately I can let him tell his own story. In 1937 Ernest R. 
Hilgard asked Watson the question we are raising here today, and he has kindly per- 
mitted me to give you Watson’s answer: 
I cannot say that either Pavlov or Bechterev had much influence in shaping m early 
a seminar I gave on Bechterev’s Objective Psychology, I repeatedly pointed out that 
he was a parallelist at heart. 
I felt the same about Pavlov. Even in 191 1 and 1912 when 1 was publishing my own 
views, neither had helped me much. I had worked the thing out in terms of HABIT 
formation. It was only later, when I began to dig into the vague word HABIT that 1 
saw the enormous contribution Pavlov had made, and how easily the conditioned 
response could be looked upon as the unit of what we had all been calling HABIT. 1 
certainly, from that point on, gave the master his due credit. 
Pavlov’s work and the work of his students were so much more accurate and com- 
rehensive in technique that it is small wonder he received the credit over Bechterev. 
!lease don’t get the im ression that I discount Bechterev’s work in any way. We 
the war broke out. 
Lashley deserves far more credit than I for the early conditioned reflex in the coun- 
try. You will remember that I said he had done most of the work,in my presidential 
address. [Watson’s address was published as “The Place of the Conditioned Reflex 
in Psychology” in 1916.’ In it he considered Pavlov’s work on sensory discrimina- 
tion as an alternative to introspection.] 
It has been a long time since I’ve read the old article of mine in the Encyclopedia 
Brirannica on Behaviorism. I think I wrote it about 1928. Possibly my memory was 
fresher then on those to whom credit is due.a 
What Watson remembered in 1928 was this: 
The work of Pawlow and his students on the conditioned reflex, while known to the 
behaviourists, played at first a relatively minor role in their formulations. This was 
B. F. SKINNER is Edgar Pierce Professor of Psychology, Emeritus, at Harvard University. 
William James Hall, 33 Kirkland St.. Cambridge, M A 02138. USA. He is of course a leading figure 
in the field ofpsychology. His most recent book is the second volume of his autobiography. The Shap- 
ing of a Behaviorist (New York: Knopf. 1979). 
242 
convictions. I never thought either of them was an objectivist. As a matter of r act, in 
used to correspond and P had made all arrangements for Lashley to go to him when 
PAVLOV’S JNFLUENCE ON AMERICAN PSYCHOLOGY 243 
due to the fact that his experiments were chiefly concerned with conditioned glan- 
dular reflexes, which was at that time a subject hardly touched upon by psy- 
chologists. Bechterev’s work on the conditioned motor reflex, where human subjects 
were used, had from the first a very much greater influence upon behaviourism. The 
work of Lashley in conditioning the human salivary reflex and of Watson and 
Rayner on conditioning human emotional reaction (fear) showed the reat range of 
ap lication of the conditioned reflex methods to human behaviour. #his work has 
l J t o an attempt to formulate all habit (organization) in terms of conditioned glan- 
dular and motor reaction. In spite of the fact that behaviourism did not at first 
utilize to any extent the conditioned reflex methods, Pawlow and Bechterev must be 
looked upon as furnishing the keystone to its arch. During the period of the eneral 
or as a specialized method in psyc i ology, the writings of E. B. Holt, A. P. Weiss, 
and K. S. Lashley are noteworthy. 
formulation of behaviourism as a s stem rather than as an approach to psyc I! ology, 
As Watson said, a salivary response was not of great interest to American psy- 
chologists, and subsequent work on the responses of glands and smooth muscles was not 
extensive. Lashley invented a method of collecting saliva from the parotid gland in 
humans, but in his Brain Mechanisms and Intelligence,’ published in 1929, he refers only 
a few times to conditioning and then critically. In 1922 Hulsey Cason reported a con- 
ditioned pupillary reflex: and some work was done on the galvanic skin response, but the 
best known psychologists in the 1920s were almost untouched. Walter S. Hunter made 
very little use of Pavlov’s work, although in 1933 a student of his, C. V. Hudgins, 
published an attempt to reduce voluntary behavior to a conditioned reflex. (A subject 
said “Contract” and a bright light was flashed in her eye. Eventually the pupil contracted 
when she said “Contract.”) Edward C. Tolman rejected the conditioned reflex formula in 
its entirety. In 1929 Clark L. Hull wrote a paper called “A Functional Interpretation of 
the Conditioned Reflex,”’ and he was responsible for much of the interest in Pavlov dur- 
ing the next decade. In 1932 one of his students, W. M. Lepley, suggested that the con- 
ditioned reflex might explain verbal learning and for years Hull referred to this as the 
“Lepley Hypothesis.” However, in his Principles of Behavior: published in 1943, he does 
not mention LeDley. 
In the thirties, Hilgard and Marquis studied the conditioned eyelid reflex.’ With its 
double innervation, this raised a new issue, which became clearest when Americans 
turned to the so-called conditioned motor reflexes of Bechterev. In 1924 Watson 
published a paper on conditioned finger withdrawal; and one of Hull’s students, Helen 
Wolfle, investigated certain temporal properties of that reflex in 1930.’O In 1928 Harold 
Schlosberg reported a conditioned patellar reflex” and in the same year Howard Liddell 
published his extensive work on conditioned leg flexion in sheep.‘l 
The trouble was that these arrangements involved consequences of behavior as well 
as antecedents. The organism escaped from or avoided an aversive stimulus-a puff of 
air in the case of the eyelid reflex or an electric shock in the case of finger withdrawal or 
leg flexion. The issue was not clarified for some time. In his article in the Encyclopedia 
Britannica Watson traced a concern with the consequences of behavior to C. Lloyd 
Morgan and Edward L. Thorndike. Much later Tolman spoke of “purposive behavior” 
and used mazes which seemed to show the goal-directedness of behavior. In 1928 two 
Polish physiologists, J. Konorski and S. Miller, added a consequence to a reflex. They 
delivered a shock to the leg of a dog, and after the leg flexed, they gave the dog food. 
Eventually the dog flexed its leg in the absence of the shock. In November 1931 they went 
to Leningrad to persuade Pavlov to change his theory. In a meeting on 20 April 1932 
244 B. F. SKINNER 
(one of the meetings which came to be called “Pavlov’s Wednesdays”) Pavlov mentioned 
Konorski and Miller and credited them with having made conditioned reflexes into “con- 
ditioned stimuli for either attractive or noxious substances.”18 
I wasstruggling with the same problem at that time. I had been impressed by 
Pavlov’s Conditioned Reflexes,“ and in my early publications I referred to the behavior I 
was studying (pressing a lever) as a reflex, but as I have pointed out in The Shaping ofa 
Behaviorist,16 before publishing my results I distinguished between two types of con- 
ditioning. 
In Type I, as in Pavlov’s experiment, a new reflex is formed. The dog salivates in 
response to a tone, for example. In Type 11, as in my experiment, two reflexes are 
‘chained together. . . and. . , remain in that relation (the lever is pressed and the 
pellet is eaten).”1e 
That we were studying very different processes became clear when we began to rein- 
force only intermittently. (This was the second occasion when I could call myself 
Pavlov’s contemporary). Pavlov found it very hard to sustain behavior if food was not 
always paired with the conditioned stimulus, but rats pressed a lever rapidly and for long 
periods of time even though reinforcement was infrequent. 
In many arrangements used to study conditioned leg flexion, the shock was ter- 
minated as the foot was lifted off the electrode. When the electrode was fastened to the 
foot, the leg presumably continued to flex until the experimenter terminated the shock, in 
which case similar contingencies prevailed. In 1936 Elmer Culler, one of those most ac- 
tive in studying the conditioned flexion reflex, gave a paper at the annual meeting of the 
American Psychological Association at which I was asked to be a discussant. I again 
raised the question of the role of consequences. It seemed to me that the only possible ex- 
ample of a skeletal response fitting the Pavlovian formula was the patellar reflex studied 
by Schlosberg, but when I asked Schlosberg about the possible role of consequences, he 
replied that they certainly had to be taken into account. 
It has been pointed out by R. M. Church” that the conditioned emotional response 
studies by Watson and Rayner also involved consequences. The rabbit and the loud noise 
were not paired; the noise occurred when Albert reached for the rabbit. The noise was 
better described as punishment. But it is possible that punishment works through the 
conditioning of aversive stimuli, and in any case autonomic responses were clearly in- 
volved. 
In 1940 W. K. Estes and I studied a different kind of conditioned emotional reaction 
in what we called ‘‘anxiety.’’’8 We reinforced pressing a lever on a fixed-interval schedule 
until a stable performance was maintained. Midway during a session we sounded a tone 
for three minutes and then shocked the rat through the feet. Originally, neither the tone 
nor the shock seriously disrupted the performance, but slowly the behavior in the 
presence of the tone was suppressed. It is a very reliable effect and has been widely used, 
Brady and Hunt, for example, found that electroconvulsive shock, as well as tranquiliz- 
ing drugs, eliminates the conditioned suppression. Although the tone no doubt elicits 
glandular and smooth muscle responses, the suppression is not, strictly speaking, a con- 
ditioned reflex. “Reaction,” a broader term, might be used, but even so the effect does 
not fit the pattern of stimulus substitution since no unconditioned stimulus produces the 
suppression. It is also possible that the conditioned salivation studied by Pavlov was not 
simply the salivation elicited by foodstuffs in the mouth transferred to an auditory 
stimulus; it could have been an innate response which would be elicited only when it 
became attached to a novel stimulus. 
PAVLOV’S INFLUENCE ON AMERICAN PSYCHOLOGY 245 
Although Pavlov’s influence on experimental psychology was not great, various 
practices in behavior therapy have clearly been derived from his work. Desensitization is 
often no more than Pavlovian extinction. Curiously enough, Pavlov has had a more 
profound effect upon amateur psychologists. Literary critics, political writers, and many 
others use the term “conditioned reflex” with abandon. Aldous Huxley was reasonably 
on target in Brave New World,1g but it is not fair to call brainwashing “pavlovization.” 
The popular usage often overrides the professional. Behaviorists have been victims of 
what might be called filial regression, as whatever they do is forced into the pattern of 
Pavlovian conditioning. Many years ago students in introductory psychology at Colum- 
bia worked with operant conditioning. The Columbia Jester published a cartoon showing 
two rats in a box, one of them saying to the other, “Boy, have I got this guy conditioned! 
Every time I press the bar down he drops in a piece of food.” It was not long before the 
story was told this way: “Gee, have I got this fellow conditioned. Every time I ring the 
bell he gives me food.” That is Pavlov’s bell. 
NOTES 
I . 
Bulletin 6 (1909): 257-273. 
Robert M. Yerkes and S. Morgulis, “The Method of Pawlow in Animal Psychology,” Psychological 
2. John B. Watson, “The Placc of the Conditioned Reflex in Psychology,” Psychological Review 23 (1916): 
89-117. 
3. Personal Correspondence, Watson to Hilgard, 1937. 
4. Encyclopedia Britannico, 14th Ed., 1928. 
5. Karl S. Lashley, Brain Mechanisms and Intelligence (Chicago: University of Chicago Press, 1929). 
6. Haulsey Cason, “The Conditioned Pupillary Reaction,” Journal of Experimental Psychology 5 (1922): 
7. Clark L. Hull, “A Functional Interpretation of the Conditioned Reflex,” Psychological Review 36 (1929): 
8 . Clark L. Hull, Principles of Behavior (New York: Appleton-Century, 1943). 
9. Ernest R. Hilgard, “Reinforcement and Inhibition of Eyelid Reflexes,” Journal of General Psychology 8 
10. Helen M. Wolfle, “Time Factors in Conditioning Finger-Withdrawal,” Journal of General Psychology 4 
I I . Harold A. Schlosberg, “A Study of the Conditioned Patellar Reflex,” J O W M ~ of Experimental 
12. Howard S . Liddell and 0. D. Anderson, “Certain Characteristics of Formation of Conditioned Reflexes 
in Sheep.” Proceedings of the Society of Experimental Biology and Medicine 26 (1928): 81-82. 
13. K. Jerzy Konorski and S. Miller, see H. D. Kimmel, Notes from “Pavlov’s Wednesdays”: “Pavlov’s Law 
of Efiect.” American Journal of Psychology 89 (1976): 553-556. 
14. Ivan ‘P. Pavlov, Conditioned Reflexes (London: Oxford University Press, 1927). 
15. B . F. Skinner, The Shaping o f a Behaviorist (New York: Knopf, 1979) . 
16. B. F. Skinner, “On the Rate of Formation of a Conditioned Reflex,” Journal of General Psychology 7 
(1932): 276286. 
17. Russell M. Church, “The Role of Fear in Punishment” in Punishment, ed. R. H. Walters, J. A. Cheyne, 
and R. K. Banks (Harmondsworth, England: Penguin Books, 1972). 
18. William K. Estes and B. F. Skinner, “Some Quantitative Properties of Anxiety,” Journal of Erperimen- 
tal Psychology 29 (1941): 390-400. 
19. Aldous Huxley. Brave New World (New York: Harper & Row, 1932). 
108-146. 
498-5 11. 
(1933): 85-113. 
(1930): 372-379. 
Psychology 1 1 (1928): 468-494.