Ch. 4 Flashcards
(39 cards)
acquisition
In classical conditioning, acquisition refers to the process of developing and strengthening a conditioned response through repeated pairings of a neutral stimulus (NS) with an unconditioned stimulus (US).
In general, acquisition proceeds rapidly during early conditioning trials and then gradually levels off.
asymptote of conditioning
The maximum amount of conditioning that can take place in a particular situation is known as the asymptote of conditioning.
asymptote of conditioning, as well as the speed of conditioning, is dependent on several factors.
In general, more intense USs produce stronger and more rapid conditioning than do less intense US.
Similarly, more intense NSs result in stronger and more rapid conditioning than do less intense NSs.
Extinction
a conditioned response is weakened or eliminated when the conditioned stimulus (CS) is repeatedly presented in the absence of the US.
Extinction also applies to the procedure whereby this happens, namely the repeated presentation of the CS in the absence of the US.
The process of extinction is the decrease in the strength of the CR, and the procedure of extinction is the means by which this is carried out, namely the repeated presentation of the
metronome without the food.
Extinction procedure
Suppose, for example, that a metronome has been paired with food such that it now elicits a conditioned response of salivation:
Metronome (NS): Food (US) - >Salivation (UR)
Metronome (CS) - >Salivation (CR)
If we now continue to present the metronome by itself and never again pair it with food (each presentation of the metronome being known as an “extinction trial”), the conditioned response of salivation will eventually die out -that is, the CR of salivation will have been extinguished.
Metronome (“NS”) - >No Salivation (-)
The process of extinction is the decrease in the strength of the CR, and the procedure of extinction is the means by which this is carried out, namely the repeated presentation of the metronome without the food.
How phobias impact extinction
The tendency to avoid a feared event is a major factor in the development and
maintenance of a phobia, and treatment procedures for phobias are often based on preventing this avoidance response from occurring.
Once a CR has been extinguished, one should not assume that the effects of conditioning have been completely eliminated.
Extinction doesn’t completely go away
Once a CR has been extinguished, one should not assume that the effects of conditioning have been completely eliminated
For this reason, in the preceding diagram, the “NS” following extinction has been placed in quotation marks, since it is no longer a pure neutral stimulus.
For one thing, a response that has been extinguished can be reacquired quite rapidly when the CS (or NS) is once again paired with the US.
As further evidence that extinction does not completely eliminate the effects of conditioning, an extinguished response can reappear even in the absence of further pairings between the CS and US.
Ex: extinguish a dog’s conditioned salivary response to a metronome by repeatedly presenting the metronome without food. —> by end of day it’s gone. —> come back tomorrow, has it again —> repeat extinction procedure daily —> until one day you come in and the 1st time do it, dog doesn’t respond.
Spontaneous recovery
is the reappearance of a conditioned response to a CS following a rest
period after extinction. Fortunately, spontaneous recovery does not last forever.
Each time the response recovers, it is usually weaker and extinguishes more quickly than before.
Therefore, after several extinction sessions, we should be able to sound the
metronome at the start of the session and find little or no salivation.
is particularly important to remember when attempting to extinguish a conditioned fear response.
To Pavlov (1927), the phenomenon of spontaneous recovery
indicated that extinction is not
simply a process of unlearning the conditioning that has taken place.
Rather, extinction involves learning something new, namely, to inhibit the occurrence of the CR in the presence
of the CS.
Spontaneous recovery may therefore represent the partial weakening of this inhibition during the rest period between extinction sessions.
Support for the notion that extinction involves a buiIdup of inhibition is also provided by a phenomenon known as disinhibition.
Disinhibition
is the sudden recovery of a conditioned response during an extinction procedure when a novel (unfamiliar) stimulus is introduced.
Disinhibition example
if we are in the process of extinguishing conditioning to a metronome but then present an unusual humming noise in the background, the sound of the metronome may again elicit a considerable amount of salivation.
(Step 1: First condition the metronome as a CS for salivation)
Metronome (NS): Food (US) - >Salivation (UR)
Metronome (CS) - >Salivation (CR)
(Step 2: Begin extinction trials by repeatedly presenting the metronome by itself; as a result, the CR is greatly weakened)
Metronome (CS) - >Weak salivation (partially extinguished CR)
(Step 3: Present a novel humming noise in background during the extinction procedure; as a result, the CR recovers in strength)
(Unusual humming noise) Metronome (CS) - >Salivation (full CR)
phenomenon of disinhibition is similar to dishabituation
dishabituation involves the reappearance of a habituated response,
and
disinhibition involves the recovery of a response that has become partially inhibited due to extinction.)
Extinction is not the same as forgetting.
The key difference, therefore, is that in extinction, a CR is eliminated because of repeated exposure to the CS in the absence of the US, whereas forgetting simply requires the passage of time and does not require repeated exposure to the CS in order for the CR to be eliminated.
stimulus generalization
is the tendency for a CR to occur in the presence of a stimulus that is similar to the Cs. In general, the more similar the stimulus is to the original CS, the stronger the response.
The process of generalization is most apparent when the stimuli involved are physically similar and vary along a continuum.
Semantic generalization
is the generalization of a conditioned response to verbal stimuli that are similar in meaning to the CS.
meaning of the word is the critical factor in semantic generalization.
For example, if humans are exposed to a conditioning procedure in which the sight of the word car is paired with shock, that word eventually becomes a CS that elicits a fear response. When participants are shown other words, generalization of the fear response is more likely to occur to those words that are similar in meaning to car, such as automobile or truck, than to words that look or sound similar, such as bar or tar.
stimulus discrimination
the tendency for a response to be elicited more by one stimulus than another.
Discriminations can be deliberately trained through a procedure known as discrimination training.
Discrimination training is a useful means for determining the sensory capacities of animals.
For example, a dog salivates in the presence of the 2000-Hz tone but not in the presence of a 1900-Hz tone, then we say that it is able to discriminate, or has formed a discrimination, between the 2 stimuli.
discrimination training
The discrimination training has, in effect, countered the tendency for generalization to occur.
Repeatedly present the dog with one type of trial in which a 2000-Hz tone is alwavs followed by food and another type of trial in which a 1900-Hz, tone is never followed by food, the dog will soon learn to salivate in the presence of the 2000-Hz tone and not in the presence of the 1900-Hz tone.
Step 1: Conditioning phase (with the two types of trials presented several times in random order) (if not in random order, dog might associate the presentation of food with every second tone rather than with the tone that has a pitch of 2000 Hz.)
2000-Hz tone (NS): Food (US) - >Salivation (UR)
1900-Hz tone (NS): No Food (- )
Step 2: Test phase
2000-Hz tone (CS+ ->Salivation (CR)
1900-Hz. tone (CS-) - > No salivation ( )
As a result of training, the 2000-Hz tone has become an excitatory CS (or CS+) because it predicts the presentation of food, and the 1900-Hz tone has become an inhibitory CS (or CS-) because it predicts the absence of food.
Generalization and discrimination play an important role in many aspects of human behavior. Ex: Phobias
involve not only the classical conditioning of a fear response, but also an overgeneralization of that fear response to inappropriate stimuli.
Ex: woman who has experienced an abusive relationship with a man may develop feelings of anxiety and apprehensiveness toward most men.
Eventually, however, through repeated interactions with men who are not abusive, this tendency can decrease and she can begin to adaptively discriminate between men who are potentially abusive and those who are not.
Unfortunately, such discriminations are not always easily made, and further bad experiences could greatly strengthen her fear.
Moreover, if the woman begins to avoid all men, then the tendency to overgeneralize may remain, thereby significantly impairing her social life.
if we avoid that which we are afraid of, it is difficult for us to overcome our fears.
Experimental Neurosis
Pavlov (1927, 1928) reported an interesting discovery made by a colleague, Shenger-Krestovnikova, that arose during a discrimination training procedure.
An experimentally produced disorder in which animals exposed to unpredictable events develop neurotic-like symptoms.
Pavlov hypothesized that human neuroses might develop in a similar manner. Situations of extreme uncertainty can be stressful, and prolonged exposure to such uncertainty might result in the development of neurotic symptoms.
Experimental Neurosis example
Image of a circle signaled the presentation of food and an ellipse signaled no food.
Normal processes of discrimination, the dog duly learned to salivate when it saw the circle (a CS+) and not salivate when it saw the ellipse (a CS-).
Following this, the ellipse was gradually made more circular, making it more difficult for the dog to determine when food was about to appear.
When the ellipse was almost completely circular, the dog was able to make only a weak discrimination, salivating slightly more in the presence of the circle than in the presence of the ellipse.
Interestingly, continued training with these stimuli did not result in any improvement.
In fact, after several weeks, the discrimination was lost. More interestingly, however, the hitherto well-behaved dog became extremely agitated during each session-squealing, wriggling about, and biting at the equipment.
It acted as though it were experiencing a serious emotional breakdown.
Pavlov formulated a theory of personality
discovered that different dogs displayed different symptoms.
Some dogs became anxious when exposed to the procedure, while others became catatonic (rigid) and acted almost hypnotized.
Others, displayed few if any symptoms and did not have a breakdown.
Pavlov speculated that such differences reflected underlying differences in
temperament.
This was an extension of one of Pavlov’s earlier observations that certain dogs
condition more easily than others.
Shy, withdrawn dogs seemed to make the best subjects, conditioning easily, whereas active, outgoing dogs were more difficult to condition (which is quite the opposite of what Pavlov had originally expected).
Based on results such as these, Pavlov formulated a theory of personality in which inherited differences in temperament interact with classical conditioning to produce general patterns of behavior.
Eysenck (1957) later utilized certain aspects of Pavlov’s work in formulating his own theory of personality.
A major aspect of Eysenck’s theory is the distinction between introversion and extroversion.
In very general terms,
introverts are individuals who are highly reactive to external stimulation (hence, cannot tolerate large amounts of stimulation and tend to withdraw from such stimulation), condition easily, and develop anxiety-type symptoms in reaction to stress.
Extroverts are less reactive to external stimulation (hence, can tolerate, and will even seek out, large amounts of stimulation), condition less easily, and develop physical-type symptoms in reaction to stress.
Eysenck’s theory also proposes that psychopaths,…
individuals who engage in antisocial behavior, are extreme extroverts who condition very poorly.
As a result, they experience little or no conditioned anxiety when harming or taking advantage of others, such anxiety being the underlying basis of a conscience.
Both Pavlov’s and Evsenck’s theories of personality
are considerably more complicated than
presented, involving additional dimensions of personality and finer distinctions between
different types of conditioning, especially excitatory and inhibitory conditioning.
Thus, extroverts do not always condition more poorly than introverts, and additional factors are presumed to influence the development of neurotic symptoms.
Nevertheless, processes of classical conditioning interacting with inherited differences in temperament could well be major factors in determining one’s personality.
The experimental neurosis paradigm also suggests that prolonged exposure to unpredictable events can sometimes have serious effects on our well-being.
Higher-Order Conditioning
a stimulus that is associated with a CS can also become a CS.
In reality, however, modern researchers use other procedures to study classical conditioning, such as the conditioned suppression procedure.
We could also attempt third-order conditioning by pairing yet another stimulus.
However, third-order conditioning can be experimentally difficult to obtain, and when it is obtained, the conditioned response to a third-order conditioned stimulus (the CS ) is likely to be quite weak.
Higher-order conditioning is commonly used in advertising.
For example, advertisements often pair a product with celebrities who, through past conditioning, have come to elicit positive emotional responses in many of us.
The assumption is that the sight of the celebrity will elicit a positive emotional response in us that will be associated with the product and thereby increase the likelihood that we will purchase the product.
