Chapter 2 Early Behaviorism
The Beginnings of Scientific Psychology
The Structuralism movement was in full swing in Europe (Wilhelm Wundt and Edward Titchener)
The onset of Functionalism began in the United States (William James)
Introspection was the primary research methodology; however, a more scientific method,
psychophysics, was emerging
Wilhelm Wundt (1832 – 1920)
Born in Mannheim, Germany
Upbringing was extremely strict
Early school career was difficult and very unsuccessful
Fascinated by anatomy and the mysteries of the brain while in college
Obtained a doctorate by age 24
Founded the psychological lab at the University of Leipzig
Wrote more than 500 books and articles
Early Psychophysics
Early psychologists were seeking through psychophysical measurements the least amount of stimulation
required for sensation (i.e., absolute threshold).
Determining a generalized absolute threshold is not possible as some people are more sensitive than
others.
For each individual there is a lower limit below which a stimulus will never be detected and an upper
limit above which it will always be detected. Between the two, there is a point at which it will be
detected 50% of the time. This point is called the absolute threshold, although it is more approximate
than absolute.
Psychophysicists tried to measure not only absolute thresholds but also what they called the differential
threshold often referred to as the just noticeable difference (JND).
JND = the least amount of change in stimulation that would be noticeable
Max Weber concluded that JNDs are a constant proportion of a stimulus (i.e., Weber’s Law).
Weber’s Law
A graphic portrayal of Weber’s law. As intensity of stimulation increases, proportionally greater
increases in stimulation are required if they are to be noticeable
Ivan Petrovich Pavlov (1849 – 1936)
Set out to become a priest like his father
Performed poorly in elementary school
While in seminary, he became fascinated with Russian translations of Western scientific writings with
Darwinian overtones
Left the seminary to pursue studies at the University of St. Petersburg in animal physiology and in
medicine
Began his famous classical conditioning experiments at age 50
While visiting the United States at age 74, he was mugged in Grand Central Station
Insisted he was a physiologist not a psychologist, and fined any laboratory assistant who used
psychological rather than physiological terms
Classical Conditioning
Pavlov’s most famous experiments resulted from almost accidental observations.
While studying digestive juices, Pavlov noted that some dogs created saliva prior to feeding.
In seeking a scientific explanation for the dogs’ early salivation, he created the now-famous
experiments.
Pavlov demonstrated that not only could the sight of food eventually bring about salivation in his dogs,
but almost any other distinctive stimulus could have the same effect if paired with food often enough.
What Pavlov first noticed was that the sight of the handler alone was enough to cause many of his
experimental dogs to salivate. Through further experiments, he studied the learning processes involved.
In these experiments the stimulus food or other stimuli such as a buzzer that is paired with the food,
which are controlled by experimenter, are independent variables. The dogs response (salivation, in this
case) is a dependent variable.
In his demonstration, Pavlov refers to the food as an unconditioned stimulus (US).
The salivation in response to the food is called an unconditioned response (UR).
An unconditioned response is a response that occurs without any learning.
What Pavlov showed repeatedly is that if a US (food, for example) is paired with another stimulus often
enough, this other stimulus will eventually lead to the response originally associated only with the US (in
this case, salivation).
If a buzzer is sounded every time food is presented to the dog, eventually the buzzer—called a
conditioned stimulus (CS)—will elicit the response of salivation—now a conditioned response (CR).
In his experiments, Pavlov often placed his dogs in a harness like this one. Food powder (an independent
variable controlled by the experimenter) can be placed either in the dog’s mouth or in the dish. A tube is
surgically inserted into the duct of the parotid gland so that the amount of saliva produced (a dependent
variable) can be measured as it drops down the tube, causing movement in a balancing mechanism at
the other end of the tube. This movement is in turn recorded on a revolving drum. In the experiment
illustrated here, the US (food) is paired with a CS (light shining in the window).
Classical conditioning.
Food (US) elicits salivation in a dog, but a buzzer (NS) does not. After successive pairing of food and
buzzer, the buzzer (CS; an independent variable) begins to elicit salivation (CR; a dependent variable).
Learning through stimulus substitution
Signal learning
Learning always begins with an unlearned response (UR) that can reliably be elicited by a specific
stimulus (the US). This unlearned stimulus-response unit is called a reflex.
Reflexes
Simple, non-intentional, unlearned behaviors
Pre-wired stimulus-response units
Humans are born with a number of reflexes:
Sucking reflex
Moro reflex
Knee-jerk reflex
Eye-blink reflex
Pupillary reflex
Reflexive responses can be classically conditioned
Contiguity and Reinforcement
Contiguity: the simultaneous or nearly simultaneous occurrence of events
for behavior to change (that is, for learning to occur), it is sufficient that two events be paired—
sometimes only once, sometimes more often
Reinforcement: a more complex concept having to do with the effects of a stimulus (e.g., positive
reinforcement)
Variations in Contiguity
Contiguity ≠ Contingency
Pavlovian conditioning is based on contiguity rather than contingency
Variations in contiguity
Simultaneous pairing: the CS starts and ends at exactly the same time as the US
Delayed pairing: the CS is presented before the US and continues during presentation of the US
Trace pairing: the CS starts and ends before the US so that there is a very brief time lapse between the
two
Backward pairing: the US has already been presented and removed before presentation of the CS
Variations in Contiguity
Impact of variations in CS-US procedures. The pairing sequences are shown here in the order of
effectiveness. Conditioning takes place most quickly in the delayed sequence, when the conditioned
stimulus (for instance, the buzzer) is presented shortly before the unconditioned stimulus (food powder)
and continues throughout the time the US is presented.
Backward Conditioning and Biological Predispositions
Backward conditioning (backward pairing):
long thought to be completely ineffective
in an increasing number of experiments, investigators have succeeded in bringing about backward
conditioning
Biological predispositions: growing evidence that some types of learning are far easier for certain
organisms than are other types
Findings in Classical Conditioning
Acquisition
The formation of the stimulus-response association typically requires a number of pairings of CS and US.
A hypothetical learning curve is portrayed to the right. Note that the strength of the conditioned
response increases rapidly at first and then levels off.
Learning curves are affected by the number of US-CS pairings and by the strength of the US. In general,
the stronger the US, the more quickly the CR will reach its peak.
Extinction and Recovery
Classically conditioned responses can be eliminated—a procedure that Pavlov called extinction.
One way to extinguish a conditioned response is to present the conditioned stimulus repeatedly without
the unconditioned stimulus.
However, if the CS is presented again later, the CR reoccurs, although at lower intensity—a
phenomenon called spontaneous recovery.
To completely extinguish the response, it would be necessary to present the CS without the US again—
and perhaps to repeat the procedure a number of different times.
A hypothetical representation of spontaneous recovery following extinction. Note how the strength of
the CR is less following each extinction period, and how progressively fewer trials are required for
extinction.
Stimulus Generalization: making the same, or similar, responses when presented with any of a number
of related stimuli
Stimulus Discrimination: making different responses to related but distinctly different stimuli
Higher Order Conditioning
responses, stimuli, and reinforcers linked in complex ways
Educational Implications of Classical Conditioning
Classical conditioning, especially of emotional responses, occurs in all schools, at all times.
Teachers need to do whatever they can to maximize the frequency, distinctiveness, and potency of
pleasant unconditioned stimuli in their classrooms.
Teachers need to try to minimize the unpleasant aspects of classroom learning to reduce the number
and potency of negative unconditioned stimuli in their classrooms.
Teachers need to know what is being paired with what in their classrooms.
John Broadus Watson
Founder of American behaviorism
Worked his way through the University of Chicago graduate school as a rat caretaker
At age 29, Watson was offered a full professorship at Johns Hopkins
Edited one of the most influential publications in psychology, Psychological Review
At age 36, became president of the American Psychological Association (APA)
The study for which he is most famous involved the child, Little Albert
Scandal forced his resignation from Johns Hopkins
Became an advertising executive and vice president of the J. Walter Thompson Company
Before his death in 1958, the APA honored him for his outstanding contributions to psychology
Behaviorism
Human actions, says can be understood through actual behaviors that can readily be observed and
studied.
Introspection forms no essential part of human psychological methods.
Behavior consists of responses that can be observed and related to other observable events, such as
conditions that precede and follow behavior.
Behaviorists tried to limit psychology to the study of actual, observable behaviors.
Watson’s Learning: A Classical Conditioning Explanation
Humans are born with a number of reflexes
Physical
Emotional
Reflexes can be brought about by specific stimuli
Conditioned Emotional Reactions
According to Watson, emotional behavior, like all other behavior, is simply another example of classical
conditioning.
All people are born with the same emotional reflexes (i.e., fear, love, rage, etc.).
People acquire conditioned emotional reactions. Watson proposed to explain this important
phenomenon using classical conditioning.
Later emotional reactions, he explained, result from the pairing of initially neutral stimuli with stimuli
that are associated with emotional responses.
To illustrate this belief, Watson conducted his famous and controversial investigation: the study of Little
Albert.
Transfer: the making of similar responses for a variety of related stimuli.
Emotional responses are conditioned to various stimuli as a result of pairings that occur between
conditioned stimuli such as distinctive sounds, smells, sights, or tastes, and unconditioned stimuli such
as those that produce fear or love or anger.
Emotional responses can spread to stimuli to which they have not been conditioned, but that resemble
conditioned stimuli.
Positive Emotions
It is possible to condition negative emotional reactions by repeatedly pairing a stimulus ordinarily
associated with some negative emotion with another distinctive stimulus.
It is also possible to condition positive emotional reactions to neutral stimuli.
Counterconditioning can be used to reverse the associated reactions.
Controversy with Watson’s Little Albert study
N=1
Watson seemed unclear about what he did with Albert
Some of Albert’s reactions could be attributed to not allowing Albert to suck his thumb
Watson’s Environmentalism
Nature – Nurture Controversy:
Nature camp: Humans primarily a product of genetic makeup
Nurture camp: Humans are molded and shaped mainly by their environment
The controversy surrounding the relative roles of experience and heredity in shaping human
development is far from resolved.
Higher Learning
All learning, said Watson, is a matter of responses that are selected and sequenced.
More complex learning simply requires the conditioning of more stimulus-response sequences,
eventually leading to what he called habits.
Practical Applications of Watson’s Psychology
Watson’s unwavering conviction that experiences determine all that people do and know leads logically
to the belief that all humans are basically equal.
The theory also lends itself to rigid prescriptions for child rearing and education, as well as for training
and control in the military, in industry, and elsewhere.
The theory fails to recognize differences among individuals, it insists that people’s behavior can be
controlled through the judicious and clever arrangements of stimulus and response events
Attitudes and Emotions
Simple models of classical conditioning are very useful in explaining emotional learning.
Many emotions appear to be learned as a result of an often-unconscious process of classical
conditioning.
Classical conditioning of a math phobia
Behavior Modification
In the same way as a phobia might be acquired through classical conditioning, it might also be removed
using similar principles.
The role of classical conditioning can be applied in learning (and unlearning) behaviors.
An Appraisal of Watson’s Behaviorism
Watson’s theory, which became immensely popular in the United States, had a profound influence on
child-rearing and educational practices.
Some critics contend that Watson was probably guilty of exaggerating the role of learning in
determining behavior, and underemphasizing the role of heredity.
Watson did much to make the science of psychology more rigorous and more objective.
Watson popularized the notion that environmental experiences are potent forces in shaping behavior
patterns.
Watson elaborated a learning model (classical conditioning) that explains at least some aspects of
animal and human behaviors.
Edwin Ray Guthrie
Born and raised in rural Nebraska
Father owned a bicycle and piano shop; mother was a schoolteacher
Guthrie was a high school teacher for three years
His PhD. was in philosophy; however, his shift to psychology came in 1919
Watson was profoundly influenced by Pavlov’s classical conditioning
He is known for his irreverent writing style filled with humor and anecdotes
Dean of graduate studies at the University of Washington
Was president of the American Psychological Association
Guthrie’s Law of One-Shot Learning
“A combination of stimuli which has accompanied a movement will on its recurrence tend to be
followed by that movement”
When an organism does something on one occasion, it will tend to do exactly the same thing if the
occasion repeats itself.
The full strength of the “bond” between a stimulus and a response is reached during the first pairing; it
will neither be weakened nor strengthened by practice.
What they learn is not a connection between two stimuli (as happens in Pavlovian classical
conditioning), but a connection between a stimulus and a response.
The Role of Practice and Repetition
Note Guthrie’s use of the word ‘tend’ in his law
The outcome of any one stimulus or stimulus pattern cannot be predicted with certainty because there
are other stimulus patterns present, hence the tendency to repeat responses to particular stimuli
Practice and repetition are valuable
Practice provides an opportunity for making the same response in a wide variety of different situations
The need for repetition comes from the need for executing the act in a variety of circumstances
Movement Produced Stimuli
A stimulus is not just one sensation but, rather, is a combination of numerous sensations.
According to Guthrie, learning involves associating a response to a combination of stimuli.
Similarly, a response is not just a single, final act; rather, it is a sequence of actions.
To simplify, the sound of a bell leads to a number of alerting responses: turning the ears, moving the
eyes, perhaps moving the head and neck, and so on.
Every such motion is a stimulus to many sense organs in muscles, tendons, and joints, as well as the
occasion for changing stimuli to eyes, ears, etc.
Guthrie labeled these stimuli movement produced stimuli (MPS).
Contiguity in MPS
The sequence between the initial presentation of a stimulus and the occurrence of response is filled
with a sequence of responses and the proprioceptive (internal) stimulation that results (MPS).
Each of these responses and their corresponding MPS are in contiguity (occur at the same time), and so
each becomes associated, or learned. These learned associations are what guide behavior.
The entire sequence is learned because each individual MPS is present at the same time as the response
occurs.
One of the clearest examples of MPS is found in the learning of athletic skills, as these skills often consist
of long sequences (or chains) of responses.
Guthrie’s Law of One-Shot Learning
Guthrie’s law of one-trial learning: “A combination of stimuli which has accompanied a movement will
on its recurrence tend to be followed by that movement.” According to the theory, each overt response
is accompanied by a series of stimuli produced by the movement (changes in the visual field, in bodily
sensations, and so on). These movement produced stimuli (MPS) lead to a continuation of the overt
action—or to a change of response. Each MPS and each response in the chain is sequential and
overlapping in time (hence in contiguity). According to the theory, learning occurs through contiguity.
Habits
According to Guthrie, learning occurs in one trial, but this does not mean that a complex behavior can
be learned in one trial.
Each individual component of the vast number of stimulus-response associations that make up a
complex act requires only a single pairing.
A number of trials might be required, however, before all have been associated as they need to be.
When they are all linked so that a particular combination of stimuli reliably leads to a particular
combination of responses, what we have is a habit—a stereotyped, predictable pattern of responding.
Humans are seldom completely predictable, and they do not respond exactly the same way every time
they are placed in the same situation.
Explanations:
if responses to two stimuli are different, it’s because the stimuli are not exactly identical
it may be that through one of a number of procedures, a new habit has replaced an old one. The old one
is not forgotten—it is merely replaced
Forgetting
The best explanation for forgetting, says Guthrie, is not that associations are wiped out with the passage
of time, but that time allows new learning to replace the old.
It follows from the theory that whatever response was last performed in a stimulus situation will tend to
be repeated again when that situation next arises.
Reward and Punishment
According to Guthrie, reward doesn’t do anything to strengthen the link between stimulus and
response. But what it does is change the stimulus situation, thus preventing the animal (or person) from
learning something different.
Punishment, too, can change a stimulus situation and serve, in Guthrie’s words, to “sidetrack” a habit.
Learning depends on contiguity (that is, on the simultaneity of stimulus and response events) to be
effective, thus punishment has to occur during the response, or very soon afterward.
Because punishment works by interrupting the unwanted habit, anything that grabs attention and
brings about a different behavior will work.
Practical Applications of Guthrie’s Theory
One-shot theory of contiguity learning: to bring behavior under control, it is necessary to arrange for the
behavior to occur in the presence of stimulus conditions that you control
responses are never forgotten; they are merely replaced by more recently learned responses
the best way of breaking a habit is to find the cues that initiate the habit and to practice another
response to those same cues
Three techniques for breaking habits
Fatigue technique (flooding) involves presenting the stimulus repeatedly to elicit continued repetition
of the undesired response. Eventually the organism will become so fatigued it can no longer perform the
response.
Threshold technique involves presenting the stimulus that forms part of the undesirable S-R (for
stimulus-response) unit (habit) but presenting it so faintly that it doesn’t elicit the undesirable response.
If it doesn’t elicit the undesirable behavior, then it probably elicits another response.
Incompatible stimuli technique involves presenting the stimulus when the response can’t occur.
Because the undesirable reaction is prevented, a different response takes its place and eventually
replaces the old habit entirely.
Guthrie’s Three Ways of Breaking Habits
In (a) the horse is “broken” in the traditional sense, being allowed to buck until fatigued.
In (b) the horse is “gentled” by having progressively heavier weights placed on its back, beginning with a
blanket and culminating with a saddle and rider.
In (c) the horse is tied down so it cannot buck when mounted.
An Appraisal of Guthrie’s One-Shot Learning
The theory is relatively simple and highly practical.
Although the simplicity of the theory is one of its main attractions, it is also one of its weaknesses.
The theory lacks the sort of detail required to make clear what concepts such as habits, movement
produced stimuli, and, indeed, responses and stimuli are.
In this theory, stimuli are what lead to responses; responses are what result from stimuli. Hence, these
two variables, both of which are central to the theory, are defined only in terms of each other.
Evaluation of Early Behavioristic Theories
Pavlov, Watson, and Guthrie were concerned mainly with discovering and explaining regularities that
underlie relationships among stimuli and responses.
How good are these theories?
they fit the facts reasonably well as the facts were known then
they tend to be clear and understandable
they are relatively parsimonious
they are internally consistent
their insistence on objectivity generally means that they are not based on many unverifiable
assumptions
their contributions to the subsequent development of learning theories can hardly be overestimated
these theories have proven to be highly practical in a variety of applied situations
they serve as important precursors of contemporary theories
Weaknesses of these early behavioristic positions are that they largely ignored individual differences in
ability as well as in preferred ways of learning