Developmental psychology.pdf

180 Learning and Information Processing
Conditioning Principles
The early findings from Pavlov's laboratory have been amplified by modern research
that focuses on how this form of learning originates, how it is modified, and how it
disappears. The primary concern is with the learning process, not salivation or some
other response used for studying it. Pavlov's expectation, borne out in much subsequent
research, was that many physiological and emotional reactions are acquired in this way
(Pavlov, 1927).
*A high school friend and I were
exploring the back roads of South
Dakota late one wintry night.
Although quite inebriated, we were
marching along fairly well, and
generally having a very good time.
Then, as will happen, came the
need for a rest stop. Breathing the
crisp air and making water I spied a
fence. Deciding the fence needed
watering, I proceeded to do so. The
unfortunate result was immediate
and quite violent. The fence was
electric and I received an
unconditioned stimulus the likes of
which I'll never forget. I am to this
day extremely anxious whenever
around an electric fence.
This learning involved a delay
between the two events. I noticed
the fence and then, while still
urinating, I received the shock.
Acquisition In fact, it was through classical conditioning that the punished monk
retrained the monastery cats. His technique was described by Lope de Vega, an early
Spanish dramatist. As the monk said of the cats: "I put them all in a sack, and on a
pitch black night took them out under an arch. First I would cough, and then
immediately whale the daylights out of the cats. They whined and shrieked like an
infernal pipe organ. I would pause for a while and then repeat the operation—first a
cough, and then a thrashing. I finally noticed that even without beating them, the beasts
moaned and yelped like the very devil whenever I coughed. I then let them loose.
Thereafter, whenever I had to eat off the floor, I would cast a look around. If an animal
approached my food, all I had to do was cough, and how that cat did scat!" (Bousefield,
1955).
The cough presumably was a neutral stimulus before the beating in the sack.
It had no significant influence on the cats' behavior. Being struck with a stick, however,
was an unconditioned stimulus for the unconditioned response of fear, tension, and a
reflexive withdrawal. No learning was required. Thus, when the cough was paired with
a thrashing on several occasions, it became a conditioned stimulus, evoking the conditioned
fear response.
The acquisition of this response occurred through a form of classical conditioning
known as trace conditioning, in which the neutral or conditioned stimulus does
not appear with the unconditioned stimulus. It appears first; then disappears; and then
the unconditioned stimulus appears. The coughing occurred, and then it was terminated
before the beating began. Only a memory trace remained when the beating occurred,
and the conditioning process depended upon this trace.
The crafty monk, if he had some idea of modern research, might have tried
delayed conditioning instead, for it is by far the most common. Here the conditioned
stimulus appears first, as usual, but it is still present when the unconditioned stimulus
appears.* The monk would have begun coughing and then, while still coughing, started
to hit the cats. Coughing thus becomes a powerful signal that the beating is about to
commence, even more so than in simultaneous conditioning, in which the coughing and
beating always occur only at the same time (Figure 7.4).
Figure 7.4
Conditioning Laboratories. Note
the similarities between this modern
laboratory and the early Pavlovian
laboratory. In both instances, there
are separate rooms for the subject
and the experimenter, and the
apparatus enables the experimenter
to make controlled presentations of
stimuli. The modern laboratory,
designed for study of the human
eyeblink response, includes a oneway
vision window. In the Pavlovian
laboratory, a bell or light was typically
used as the CS and the saliva
passed through an opening in the
dog's jaw. Each drop, upon entering
the calibrated test tube, activated a
lever and stylus, which recorded the
secretion on a revolving drum.