Book and Article questions
Pierce, W. D., & Cheney, C. D. (2017). Behavior analysis and learning: A biobehavioral approach (6th ed.). New York, NY: Routledge.
1. Give a novel (not discussed in the book or in class) example of respondent conditioning- identifying the steps in the process and labeling the NS, US, CS, CR, and UR.
_________ (US) ——- ___________ (UR)
NS=
____________ (NS) + ________ (US)—- ____________ (UR)
______________ (CS)——— ______________ (CR)
2. Describe respondent habituation and give an example.
3. State the definition of contiguity and a contingency identifying the primary differences between the two.
4. Describe the process of respondent extinction and why it occurs (p. 74)
5. Describe the process of respondent generalization and why it occurs.
6. Describe the role of stimulus novelty & familiarity in the US and CS pre-exposure effects.
7. Describe 2nd order conditioning and how this could explain certain fears and phobias.
8. Describe how respondent conditioning could explain placebo effects.
9. Describe the conditioned suppression procedure.
A biological imperative faced by all creatures is to survive long enough to reproduce. Because
of this necessity, behavior related to survival and reproduction often appears to be built into the
organism. Thus, organisms are born with a range of behavior that aids survival and reproduction.
not need to be learned; it results from the organisms evolutionary history as a species. The complex
dependable when this behavior is primarily based on genetic endowment.
For most animals, survival at birth depends on being able to breathe, digest food, and move
about. When a worm is dangled over a young robins head, this stimulus elicits opening of the
mouth and chirping. The behavior of the chick is the result of biological mechanisms and is elicited
. Presumably, in the evolutionary history of robins, chicks
that presented a gaping mouth and chirped were fed more often those that did not, contributing to
by an infant ensures more effective care from the childs parents. Parents engage in a variety of
caretaking behaviors, which may have resulted in cessation of crying. Usually, parental responses
Behavior relations that predominantly are based on the genetic endowment are described as phy-
logenetic
past generations of organisms that engaged in such behavior survived and reproducedpassing
on their genes over generations. Thus, species history provides an organism with a basic repertoire
behavioral characteristics were naturally selected, as they occurred through no human action or
intervention.
Fixed-action patterns or FAPs
engage in the FAP when the appropriate releasing stimuli are presented. Fixed-action patterns have
been observed and documented in a wide range of animals and over a large number of behaviors
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male sticklebacks intrude on its territory during the mating season. The female spider Cupiennius
salei
Basically, the bird continues behaving as if the egg is present even though it has been removed. The
Sciurus vulgaris
in while storing nuts for the winter:
The squirrel . . . buries nuts in the ground each fall, employing a quite stereotyped sequence of
movement. It picks a nut, climbs down to the ground, and searches for a place at the bottom of a tree
trunk or a large boulder. At the base of such a conspicuous landmark it will scratch a hole by means
of alternating movements of the forelimbs and place the nut in it. Then the nut is rammed into place
with rapid thrusts of the snout, covered with dirt with sweeping motions and tamped down with the
forepaws.
Ethologists refer to such predictable and stereotypic behaviors as to sug-
gest that these behaviors are built in and immutable. These researchers are looking for heritable
genetic factors, which appear to account for behavior of all members of the species. On the other
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able, at least to some degree. So, given the adaptive ability of most animals, we refer to this behavior
as a modal action pattern or MAP
Turdus migratorius
very similar in construction. It is clear, however, they do not all build in the same location, or use the
same materials. There is substantial individual variation in all phases of nest construction, suggest-
form. Once started, a yawn progresses through
stopalmost like a sneeze. Yawning typi-
cally occurs in bouts, with a highly variable
inter-yawn interval, averaging about a minute.
variation about this value. Also, the pattern of
is quite stable over several weeks of obser-
vation and there is no compensation between
yawning frequency and duration. Those who
yawn for shorter durations do not do it more
frequently than others with longer durations;
also, people with longer duration yawns do
not yawn less often than those with shorter
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cise stimulus that sets off yawning is hard to
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bedtime as well. Yawning after waking is often accompanied by stretching of the arms, while yawn-
ing before bedtime usually only involves yawning without stretching. As you can see, yawning
involves stereotypic behavior of phylogenetic origin that often occurs during periods of low vig-
ilance and reduced alertnessperhaps acting to momentarily reinstate surveillance and monitor-
ing of the environment. [Note: arousal or physiological activation of the brain is a disputed cause
contagious yawning is
Sacket, 2015 for birds.]
Reaction chains are similar to FAPs, but with one major differenceeach set of responses
the behavior are removed. In the previous squirrel and nuts example, the animal continues to dig a
hole and bury the nonexistent nut, even if the nut is removed. In contrast, a reaction chain requires
performance produces stimuli that set off the next series of responses in the chain; these behaviors in
turn produce the stimuli followed by another set of responses. Presenting a stimulus that ordinarily
occurs in the middle part of the sequence activates the chain at that point rather than at the begin-
ning. Also, unlike FAPs, if the stimuli that activate behavior are removed, the sequence is disrupted.
Gasterosteus aculeatus
describe an idealized behavioral sequence. During the mating season, the reaction chain is initiated
when a male stickleback sees a female and begins a zigzag dance, displaying his red underbelly. For a
receptive female with eggs, the males display functions as a stimulus that causes the female to arch her
back and reveal her swollen abdomen. This initiates swimming by the male to a previously constructed
nest. The female follows and enters the nest with her tail protruding, causing the male to nibble at the
base of her tail and initiate the egg-
laying sequence. Once the female
has deposited her eggs, the male
ousts her from the nest, enters the
nest, and fertilizes the eggs, thereby
completing the reaction chain.
This courtship chain may
be terminated at any point if the
or inappropriate to function as a
stimulus for the next link in the
chain. Thus, red-bellied males
that skillfully perform the zigzag
dance are more likely to attract
females to their nests and fertil-
ize eggs than males that execute
the dance less skillfully. Sexual
selection, by providing more
chances to mate, ensures that
genes related to skillful execu-
tion of the dance are more rep-
resented in the next generation and that the offspring have a high probability of successful
courtship and reproduction.
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ciples that describe the relationship between a sudden loud noise and a startle response, also hold for the
relationships he discovered over a century ago generalize to a remarkable variety of stimulusresponse
relations. When food is placed in a dogs mouth, the salivary glands produce saliva. This relationship
others are particular to a species. Thus, humans are born with an array of responses elicited by
responseturning toward the stimulation with the mouth open, which then receives the nipple.
serves a similar functiongetting fed. Because these relationships are relatively invariant and bio-
logically based, we refer to the eliciting or activating event as the unconditioned stimulus (US).
The related behavior following the stimulus is called the unconditioned response (UR). The term
unconditioned –
called a
produces the unconditioned response when presented with an unconditioned stimulus. You do not choose
the UR of salivation; that is, salivation is said to be elicited by the US. This is the way the animal is
built. However, there are times and conditions described below where the US does not elicit the UR.
When repeated presentations of the US leads to a reduction of the UR, we call the process habituation.
Around 350 BC, Aristotle developed principles of association that were rediscovered by psychologists
below the knee, causing a kick, may vary from a modest to a heavy blow. The intensity of the eliciting US
describe these effects.
1. The law of the threshold is based on the observation that at very weak intensities a stimulus
will not elicit a response, but as the intensity of the eliciting stimulus increases, there is a point
at which the response is elicited. Thus, there is a point below which no response is elicited and
above which a response always occurs. The uncertainty region, where roughly 50% of the stim-
uli that are presented produce a response, is called the threshold.
2. The law of intensitymagnitude describes the relationship between the intensity of the eliciting
stimulus and the size or magnitude of the elicited response. As the intensity of the US increases, so
does the magnitude of the elicited UR
will evoke a slight jerk of the lower leg; a stronger tap will produce a more vigorous kick of the
is used to smash into the knee, the result is a broken kneecap and no movement for a long time.
3. The law of latency concerns the time between the onset of the eliciting stimulus and the appear-
these two events. As the intensity of the US increases, the latency to the appearance of the elic-
ited UR decreases. Thus, a strong puff of air will elicit a quick blink of the eye. A weaker puff
will also elicit an eye blink, but the onset of the response will be delayed.
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acteristics and one of these, habituation, has been shown in animals as simple as protozoa and as
complex as humans.
One of the more documented secondary properties habituation. Habituation
is observed to occur when an unconditioned stimulus repeatedly elicits an unconditioned response
eventually fail to occur at all. For example, Waw-
onto a slide on which the protozoa Spirostomum
ambiguum were mounted. The dropped weight
initially elicited a contraction or startle response
that steadily declined to near zero with repeated
stimulation.
An interesting report of human habituation,
in a dangerous setting, appeared in the July 1997
issue of National Geographic
small island of Montserrat has been home to
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tively silent volcano on the island reawakened in
July 1995. Suddenly, the quiet existence that had
characterized living on Montserrat was rudely
interrupted. Before the major eruption of the vol-
cano, a large group of inhabitants refused to evac-
uate the island, even though these people suffered
through several small volcanic explosions:
staying with friends in St. Johns, about as far
north of the volcano as you can get. . . . Peo-
ple could get passes to visit the unsafe zone,
morning.
If you have animals and crops, you
walked back to his truck. You have to come
look after them and hope nothing happen. As he spoke, the volcano made a crackling sound like
falls, everybody look.
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uated to near zero with repeated eruptions of the volcano. A similar process is observed when people
some time the sound is barely noticed. This decrease in the human startle response is demonstrated in a
South Dakota State. Brady notes that a human demonstration of habituation is not an experiment as the
large initially, but gets progressively smaller as habituation continues. Second, if the unconditioned
stimulus is withheld for some time, the habituated response recovers, a process called spontaneous
recovery. Third, when habituation is repeatedly produced, each series of stimulus presentations
generates progressively more rapid habituation. In other words, habituation occurs more quickly on
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On a daily basis, animals are exposed to aversive events that activate a complex stress response
repeated presentation of the stressful event. In a recent review of the HPA axis and stress neurobi-
Overall, a good deal of literature supports HPA habituation as an example of response habitua-
tion. . . . These criteria describe the well-documented phenomenon of habituation itself, its ability to
be enhanced by increased frequency or number of presentations, variations in its induction related to
the strength of stimulus, and its ability to be dishabituated by a novel stimulus. . . . However, [some]
criteria are not supported. This is due largely to the lack of demonstration of spontaneous recovery
[of HPA activity after a period without the stressor].
The authors conclude that the HPA-axis response to repeated stress is more complicated than
response habituation. The decline in HPA activity to stressful events does involve habituation, but
exposures to stressful stimuli.
Habituation is a conserved behavioral process that has come about because of a phylogenetic
history. Those animals that habituated were more likely to survive and produce offspringpassing
on their genes to the next generation. An herbivore that runs away each time the grass rustles gets
less to eat than one that stands its ground. A rustling sound of grass may indicate the presence of a
predator, or simply the wind blowing. Repeated, unnecessary activation of respondent mechanisms
also causes stress to the animal, which is not good in terms of health and physiology.
In addition to phylogenetic history, the behavior of an organism is affected by environmental expe-
rience. Each organism has a unique ontogenetic history or lifetime of conditioning. Changes in
behavior, as a result of such experiences, are called learning, consisting of moment-to-moment
interactions of the organisms behavior with the environment. Events in the physical and social
phylogenetic history to determine
when, where, and what kind of behavior will occur at a given moment.
For example, salivation is involved in the digestion of food. People do not learn to salivate to
the taste of food; this is a phylogenetic characteristic of the species. After some experience learning
that McDonalds goes with food, you may salivate to the sight of the golden arches of McDonalds,
especially if you are hungry and like hamburgers. Salivating at the sight of McDonalds arches
occurs because of respondent conditioningyou were not born that way. It is, however, important
to note that respondent conditioning and other learning processes evolved because they provided
some sort of reproductive advantage. Those organisms whose behavior came under the control of
behavior did not. Through Darwinian evolution and selection, respondent conditioning became a
means of behavioral adaptation. In other words, organisms with a capacity for respondent or asso-
ciative learning were more likely to survive and reproduceincreasing their genes in the population
Respondent conditioning involves the transfer of the control of behavior from one stimulus to
another by SS association. In Chapter 1, we saw that the sound of a bell could come to elicit sali-
vation after the bell had been associated with food. This kind of conditioning occurs in all species,
including humans, and is common in everyday life. Imagine that you are out for an early morning
walk and pass a bakery where you smell fresh donuts. When this happens, your mouth begins to
water and your stomach starts to growl. These conditioned responses occur because, in the past, the
conditioned
stimulus (CS), and salivation to the light is called the conditioned response (CR).
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of behavior control to new and often arbitrary aspects of the environment. To experience this sort
of conditioning, try the following: Read the word lemon and consider the last time you ate a slice of
lemon. Many people salivate at this CS because the word has been correlated with the sour taste of
the fruit. This shift in controlling stimulus from food to word is possible because inputs to the visual
system end up activating the neurons innervating the salivary gland.
Because the CR is a response elicited by the CS, it is often called a respondent. The terms
conditioned response and respondent are interchangeable throughout this text. The process of cor-
relating the CS with the US so that the CS comes
respondent conditioning. Technically, respondent
conditioning involves establishing a conditional
Note that the association is between the CS and
lemon and the real fruit in the
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point. The word association is sometimes taken
to mean an internal mental process that a person or
other animal performs. We hear people say, The
dog salivates when the bell is sounded because it
has associated the sound with the food. In con-
trast, a behavior analyst points to the association or
the past. In other words, the association is between
eventsit does not refer to mental associations to explain the conditioning. The word lemon
The usual measures –
and latency make sense as behavioral measures because respondent conditioning often involves
orienting to a stimulus or going to a place or location, are elicited and often confused with operant
behavior. When the CS controls behavior based on a respondent-conditioning procedure, the behav-
consequences is operant, even when this behavior involves actions of the smooth muscles, glands,
conditioned taste aversion (CTA).
Now consider a different procedure where the CS is a particular place or location and the
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the location paired with the solution, an effect known as conditioned place preference (CPP).
Notice that the tasty solution functioned as a CS for CTA conditioning, but as a US for CPP learning.
Therefore, the same stimulus or event may function as either a CS or a US, depending on its relation
to other stimuli in the situation.
When stimuli or events occur near in time or are paired together, they often become similar in
function. While close temporal proximity between CS and US is usually required, conditioning
CTA there is a substantial delay between the CS-taste onset and US-sickness, but strong conditioned
is followed by an effective US and acquires some of the behavior functions related to the US, an
equivalence relation referred to as stimulus to stimulus (SS) conditioning
by the CS response, and the person may die due to heart failure.
For most practical purposes, the conditioning procedure should arrange close temporal proxim-
ity, pairing, or contiguity of the CS and US, but research shows that it is the contingency, predictive-
ness, or correlation between the stimuli that is critical. Thus, the US should occur more frequently
when the CS is present than when it is absentthe CS should predict or signal the US
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where from moment to moment. Although many nonhuman studies of respondent conditioning are
cited in this textbook, these principles also account for an enormous amount of human behavior.
In humans, conditioning by contingency happens all the time. When the features of a person are
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life enhances many social relationships. Motherinfant bonding is a product of good USs from the
the sound of her voice, and perhaps her heartbeat, many aspects that can become very potent signals
commitment to that person. Advertising often involves enhancing product appeal by linking the item
Star Wars
preferences also transferred to other stimuli resembling those used during conditioning.
The attractiveness of the human face has been an important component in human dating and
Additional research, using brain-imaging technology, has revealed neural activity to presentations
of attractive faces in the reward areas of the brain. In the advertising industry, many television
faces can transfer to commercial products by conditioning procedures.
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active during conditioning. The results showed increases from preconditioning to postconditioning
–
–
ditioning trials in accord with the SS model of conditioning proposed by Rescorla and Wagner
conditioning works on the reward centers in the brain related to the dopamine neurons in the ventral
striatum. The results also suggest how commercial advertisements linking products with attractive
of goods and services.
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tion of the CS is called respondent acquisition
turning on the tone for a brief period, and then placing food
in a dogs mouth. Anrep measured the CR as the number
of drops of saliva during 30-s intervals wherein the tone
that the amount of salivation to the tone increases rapidly
its maximum, called the asymptote. In other words, with
repeated presentations of the CS and US, the magnitude of
the conditioned response increases. Once the conditioned
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tations have no additional effects.
It is important to note that the asymptote for the con-
ditioned response depends on the intensity of the uncondi-
tioned stimulus. As the intensity of the US increases, the
magnitude of the UR also increases up to a point. The mag-
nitude of the UR limits the maximum associative strength
of the CR. Thus, the more food a dog is given the greater
there will be more salivation than if it is presented with 30
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ated with 30 g of food. It is clear that these relationships are
limited by an organisms physiology. If a dog is given 450 g
of steak, it will probably salivate at maximum strength, and
a change to 900 g will have no further effect. Similar limits
response to light, magnitude of the knee jerk in response to a
tap, and the degree of startle in response to noise.
Notice that the conditioned response of salivation appears identical to the unconditioned response.
When conditioning to the tone has occurred, turning it on will elicit salivation. This response to
the tone seems to be the same as the salivation produced by food in the dogs mouth. In fact, early
theories of learning held that the tone substituted for the food stimulus. This implies that the CSCR
relationship is the same as the USUR relation. If the CSCR and the USUR relationships are the
same, then both should follow similar laws and principles. And the govern the
USUR relationship, as you have seen.
If the CSCR and USUR relationships are the same, then the law of intensitymagnitude
should hold for conditioned stimuli and responses. Thus, a rise in the intensity of the CS should
increase the magnitude of the CR. In addition, the CSCR relation should follow the law of latency.
An increase in the intensity of the CS should decrease the latency between the CS onset and the
not
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ditioned stimulus decreases the strength of the conditioned response. In the experiment by Anrep
–
tude and latency of salivation. If Anrep had increased the sound, there would have been less sali-
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respondent extinc-
tion. The procedure involves repeatedly presenting the CS and not presenting the US. Figure 3.5B
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sented the CS but no longer fed the dog. As you can see, the amount of salivation declines and
reaches a minimal value by the seventh trial. This minimum level of the CR is often similar to the
respondent level of this
before any known conditioning has occurred. Extinction can be valuable as a therapeutic procedure
for reducing or removing unwanted emotional responses such as claustrophobia or arachnophobia.
component. The phobic CR will then gradually decrease with repeated trials.
A distinction should be made between extinction as a procedure and extinction as a behavioral
process. The procedure involves presenting the CS but not the US after conditioning has occurred.
As a behavioral process, extinction refers to the decline in the strength of the conditioned response
when an extinction procedure is in effect. In both instances, the term extinction is used correctly.
Extinction is the procedure of breaking the CSUS association, resulting in the decline of the CR.
The decline in the strength of the CR is often rapid. This statement is true for the conditioning
of salivation, but other types of conditioned responses may vary in resistance to extinction. Even
with salivation, Pavlov noted that as the time between trials increased, the CR declined more slowly.
A test trial is any instance in which the CS is given in the absence of the unconditioned stimulus. Of
course, repeated test trials are the same as extinction. The slower extinction of salivation with longer
Spontaneous recovery is the observation of an increase in the CR after respondent extinction has
occurred. Recall that after repeated presentations of the CS without the US, the CR declines to
respondent level. Following extinction of the response to respondent level, after some time has
powder, and the US was food in the dogs mouth. As you would expect, the sight of meat powder
eventually elicited a conditioned response of salivation. When extinction began, the dog responded
no salivation to the sight of food powder, but after 20 min of rest without stimulus presentations,
the CS again elicited a conditioned response. Note, however, that the amount of salivation on the
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ship during extinction. He went on to suggest that internal inhibition came to block the connection
between stimuli and responses. Pavlov viewed conditioning phenomena as an index of brain pro-
–
ing physiological processes, and one of these
was an active but temporary dampening of
associative connections between the CS and
the conditioned response. Pavlov called this
apparent physiological blocking of the CSCR
relationship internal inhibition.
In contrast to Pavlovs hypothetical phys-
spontaneous recovery suggests that the CS
CR relation is weakened by extinction, but the
context or features of the situation in general
maintain some level of control over the condi-
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regulate behavior. For example, background odors, general illumination of the room, the presence
of particular researchers, the passage of time, and all the events that signal the start of a conditioning
series come to exert some control over the conditioned response. Each time a recovery test is made,
some part of the situation that has not yet been extinguished evokes the CR. This gradual decline in
contextual stimulus control through repeated extinction also accounts for progressively less recov-
ery of the conditioned response. The role of extinction of contextual CSs in spontaneous recovery
Pavlov conducted a large number of conditioning experiments and discovered many principles that
respondent general-
ization. Respondent generalization occurs when an organism shows a conditioned response to val-
ues of the CS that were not trained during acquisition. For example, respondent acquisition occurs
animal will salivate at maximum level. To show generalization, the researcher varies some property
the magnitude of the conditioned response
is measured. Figure 3.7 shows possible
results of such an experiment. As you can
see, the amount of salivation declines as
the test stimulus departs in both direc-
tions from the value used in training. This
graph, which plots stimulus value against
magnitude of response, is called a gener-
alization gradient.
Interestingly, a similar generalization
gradient may not occur if the intensity
rather than the tonal quality of the CS is
varied. If decibels rather than cycles-per-
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ization test, a different result might occur.
A few studies have shown that as the
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Heinemann and Chase suggest that there may be consistent increases in the strength of the CR as the
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conditions do not remain exactly the same from trial to trial. Consider a situation in which a pred-
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tions would probably not last long. This is because the events that occurred during conditioning are
never precisely repeatedeach approach of a predator produces variations in sounds, sights, and
smells. Even in the laboratory, where many features of the environment are controlled, there is some
variation in stimuli from one trial to the next. When a bell is presented and followed by food, the dog
may change its orientation to the bell and thereby alter the sound; room humidity and other factors
may also produce slight variations in tonal quality. Because of generalization, a CSCR relationship
can be strengthened even though the stimulus conditions are never exactly the same from trial to
trial. Thus, stimulus generalization is likely an adaptive process, allowing organisms to respond to
the vagaries of life.
Another conditioning principle that Pavlov discovered is called differentiation or discrimination.
Respondent discrimination occurs when an organism shows a conditioned response to one value
of the stimulus, but not to other values. A discrimination-training procedure involves presenting
both positive and negative conditioning trials. For example, a positive trial occurs when a CS such
is continued, however, the animal no longer salivates to the CS
response to the CS differential response occurs, we may say that the dog
discriminates between the tones.
Respondent discrimination is another adaptive learning process. It would be a chaotic world if an
animal spent its day running away from most sounds, sights, and smellsgeneralizing to everything.
Such an animal would not survive and reproduce as there would be no time for other essential activities
such as eating, drinking, and procreating. Discrimination allows an organism to budget its time and
responses in accord with the requirements of the environment. In the predator example, noises that are
reliably associated with an animal that considers you a main course should become CS
for such behavior. Notice, how-
observation suggests that familiar events or stimuli do not elicit as intense a reaction as novel ones.
The same is true for respondent conditioning, where novelty of the CS or US increases its effective-
respondent acquisition.
Considerable research indicates that pre-exposure to the CS weakens subsequent conditioning
with the USthe CS-pre-exposure effect Latent inhibition denotes the
inhibition of learning of the CSUS relation by pre-exposure of the CS, as revealed by an acquisition
test following the conditioning phase.
which is followed by drug-induced illness. Compared to animals without pre-exposure to the taste
acquisition. You may have had similar experiences. For example, you eat a juicy steak with your meal,
ketchup. Now consider what would happen if you had eaten sauce barnaise repeatedly with your meals
the repeated pre-exposure to the sauce barnaise without illness, it is unlikely that you will condition
to the taste of the sauce. In other words, you will not show avoidance of the sauce for your next steak
dinner. Latent inhibition and CTA have been studied extensively, and the neurophysiological under-
Other research has focused on the novelty of the US by giving pre-exposure to the US before
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slower conditioning on the acquisition testa result called the US-pre-exposure effect.
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to the drug is not due to simple habituation of the unconditioned stimulus. Research has shown that
the context in which the drug US is injected can function as a CS. Even when the drug is injected
alone, aspects of the context or background acquire CS functions. When the sweet saccharin CS is
subsequently conditioned in the same context, the contextual cues that signal the upcoming injection
block conditioning to the sweet saccharin CS, resulting in weak or no avoidance of the sweet solu-
There are several ways to arrange the temporal relation-
ship between the presentation of a CS and the uncon-
procedure in which the CS is presented a few seconds
before the US occurs. This procedure is called delayed
conditioning
Delayed conditioning is considered the most
such as salivation. In the diagram, the CS is turned
on, and 3 s later the US is presented. The interval
between the onset of the CS and the onset of the US
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ness of conditioning. For autonomic responses, such
as salivation, blood pressure, skin temperature, hor-
mone levels, and sweat secretion, a CSUS interval
of between 5 and 30 s appears to be most effective.
A brief CSUS interval
