Classical conditioning

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Classical conditioning (also known as Pavlovian or respondent conditioning) is a behavioral procedure in which a biologically potent stimulus (e.g. food) is paired with a previously neutral stimulus (e.g. a triangle). It also refers to the learning process that results from this pairing, through which the neutral stimulus comes to elicit a response (e.g. salivation) that is usually similar to the one elicited by the potent stimulus.

Classical conditioning is distinct from operant conditioning (also called instrumental conditioning), through which the strength of a voluntary behavior is modified by reinforcement or punishment. However, classical conditioning can affect operant conditioning in various ways; notably, classically conditioned stimuli may serve to reinforce operant responses.

Classical conditioning was first studied in detail by Ivan Pavlov, who conducted experiments with dogs and published his findings in 1897. During the Russian physiologist's study of digestion, Pavlov observed that the dogs serving as his subjects drooled when they were being served meat.

Classical conditioning is a basic behavioral mechanism, and its neural substrates are now beginning to be understood. Though it is sometimes hard to distinguish classical conditioning from other forms of associative learning (e.g. instrumental learning and human associative memory), a number of observations differentiate them, especially the contingencies whereby learning occurs.

Together with operant conditioning, classical conditioning became the foundation of behaviorism, a school of psychology which was dominant in the mid-20th century and is still an important influence on the practice of psychological therapy and the study of animal behavior. Classical conditioning has been applied in other areas as well. For example, it may affect the body's response to psychoactive drugs, the regulation of hunger, research on the neural basis of learning and memory, and in certain social phenomena such as the false consensus effect.

Definition

Classical conditioning occurs when a conditioned stimulus (CS) is paired with an unconditioned stimulus (US). Usually, the conditioned stimulus is a neutral stimulus (e.g., the sound of a tuning fork), the unconditioned stimulus is biologically potent (e.g., the taste of food) and the unconditioned response (UR) to the unconditioned stimulus is an unlearned reflex response (e.g., salivation). After pairing is repeated the organism exhibits a conditioned response (CR) to the conditioned stimulus when the conditioned stimulus is presented alone. (A conditioned response may occur after only one pairing.) Thus, unlike the UR, the CR is acquired through experience, and it is also less permanent than the UR.

Usually the conditioned response is similar to the unconditioned response, but sometimes it is quite different. For this and other reasons, most learning theorists suggest that the conditioned stimulus comes to signal or predict the unconditioned stimulus, and go on to analyze the consequences of this signal. Robert A. Rescorla provided a clear summary of this change in thinking, and its implications, in his 1988 article "Pavlovian conditioning: It's not what you think it is". Despite its widespread acceptance, Rescorla's thesis may not be defensible.

Classical conditioning differs from operant or instrumental conditioning: in classical conditioning, behaviors are modified through the association of stimuli as described above, whereas in operant conditioning behaviors are modified by the effect they produce (i.e., reward or punishment).

Procedures

Ivan Pavlov research on dog's reflex setup

Pavlov's research

The best-known and most thorough early work on classical conditioning was done by Ivan Pavlov, although Edwin Twitmyer published some related findings a year earlier. During his research on the physiology of digestion in dogs, Pavlov developed a procedure that enabled him to study the digestive processes of animals over long periods of time. He redirected the animal's digestive fluids outside the body, where they could be measured. Pavlov noticed that his dogs began to salivate in the presence of the technician who normally fed them, rather than simply salivating in the presence of food. Pavlov called the dogs' anticipatory salivation "psychic secretion". Putting these informal observations to an experimental test, Pavlov presented a stimulus (e.g. the sound of a metronome) and then gave the dog food; after a few repetitions, the dogs started to salivate in response to the stimulus. Pavlov concluded that if a particular stimulus in the dog's surroundings was present when the dog was given food then that stimulus could become associated with food and cause salivation on its own.

Classical Conditioning Diagram

Terminology

In Pavlov's experiments the unconditioned stimulus (US) was the food because its effects did not depend on previous experience. The metronome's sound is originally a neutral stimulus (NS) because it does not elicit salivation in the dogs. After conditioning, the metronome's sound becomes the conditioned stimulus (CS) or conditional stimulus; because its effects depend on its association with food. Likewise, the responses of the dog follow the same conditioned-versus-unconditioned arrangement. The conditioned response (CR) is the response to the conditioned stimulus, whereas the unconditioned response (UR) corresponds to the unconditioned stimulus.

Pavlov reported many basic facts about conditioning; for example, he found that learning occurred most rapidly when the interval between the CS and the appearance of the US was relatively short.

As noted earlier, it is often thought that the conditioned response is a replica of the unconditioned response, but Pavlov noted that saliva produced by the CS differs in composition from that produced by the US. In fact, the CR may be any new response to the previously neutral CS that can be clearly linked to experience with the conditional relationship of CS and US. It was also thought that repeated pairings are necessary for conditioning to emerge, but many CRs can be learned with a single trial, especially in fear conditioning and taste aversion learning.

Diagram representing forward conditioning. The time interval increases from left to right.

Forward conditioning

Learning is fastest in forward conditioning. During forward conditioning, the onset of the CS precedes the onset of the US in order to signal that the US will follow. Two common forms of forward conditioning are delay and trace conditioning.

• Delay conditioning: In delay conditioning, the CS is presented and is overlapped by the presentation of the US. For example, if a person hears a buzzer for five seconds, during which time air is puffed into their eye, the person will blink. After several pairings of the buzzer and the puff, the person will blink at the sound of the buzzer alone. This is delay conditioning.
• Trace conditioning: During trace conditioning, the CS and US do not overlap. Instead, the CS begins and ends before the US is presented. The stimulus-free period is called the trace interval or the conditioning interval. If in the above buzzer example, the puff came a second after the sound of the buzzer stopped, that would be trace conditioning, with a trace or conditioning interval of one second.

Simultaneous conditioning

Classical conditioning procedures and effects

During simultaneous conditioning, the CS and US are presented and terminated at the same time. For example: If a person hears a bell and has air puffed into their eye at the same time, and repeated pairings like this led to the person blinking when they hear the bell despite the puff of air being absent, this demonstrates that simultaneous conditioning has occurred.

 

Second-order and higher-order conditioning

Main article: Second-order conditioning

Second-order or higher-order conditioning follow a two-step procedure. First a neutral stimulus ("CS1") comes to signal a US through forward conditioning. Then a second neutral stimulus ("CS2") is paired with the first (CS1) and comes to yield its own conditioned response. For example: A bell might be paired with food until the bell elicits salivation. If a light is then paired with the bell, then the light may come to elicit salivation as well. The bell is the CS1 and the food is the US. The light becomes the CS2 once it is paired with the CS1.

Backward conditioning

Backward conditioning occurs when a CS immediately follows a US. Unlike the usual conditioning procedure, in which the CS precedes the US, the conditioned response given to the CS tends to be inhibitory. This presumably happens because the CS serves as a signal that the US has ended, rather than as a signal that the US is about to appear. For example, a puff of air directed at a person's eye could be followed by the sound of a buzzer.

Temporal conditioning

In temporal conditioning, a US is presented at regular intervals, for instance every 10 minutes. Conditioning is said to have occurred when the CR tends to occur shortly before each US. This suggests that animals have a biological clock that can serve as a CS. This method has also been used to study timing ability in animals (see Animal cognition).

The example below shows the temporal conditioning, as US such as food to a hungry mouse is simply delivered on a regular time schedule such as every thirty seconds. After sufficient exposure the mouse will begin to salivate just before the food delivery. This then makes it temporal conditioning as it would appear that the mouse is conditioned to the passage of time. 

Zero contingency procedure

In this procedure, the CS is paired with the US, but the US also occurs at other times. If this occurs, it is predicted that the US is likely to happen in the absence of the CS. In other words, the CS does not "predict" the US. In this case, conditioning fails and the CS does not come to elicit a CR. This finding – that prediction rather than CS-US pairing is the key to conditioning – greatly influenced subsequent conditioning research and theory.

Extinction

Main article: Extinction (psychology)

In the extinction procedure, the CS is presented repeatedly in the absence of a US. This is done after a CS has been conditioned by one of the methods above. When this is done, the CR frequency eventually returns to pre-training levels. However, extinction does not eliminate the effects of the prior conditioning. This is demonstrated by spontaneous recovery – when there is a sudden appearance of the (CR) after extinction occurs – and other related phenomena (see "Recovery from extinction" below). These phenomena can be explained by postulating accumulation of inhibition when a weak stimulus is presented.

Phenomena observed

Acquisition

During acquisition, the CS and US are paired as described above. The extent of conditioning may be tracked by test trials. In these test trials, the CS is presented alone and the CR is measured. A single CS-US pairing may suffice to yield a CR on a test, but usually a number of pairings are necessary and there is a gradual increase in the conditioned response to the CS. This repeated number of trials increase the strength and/or frequency of the CR gradually. The speed of conditioning depends on a number of factors, such as the nature and strength of both the CS and the US, previous experience and the animal's motivational state. The process slows down as it nears completion.

Extinction

If the CS is presented without the US, and this process is repeated often enough, the CS will eventually stop eliciting a CR. At this point the CR is said to be "extinguished."

 

External inhibition

External inhibition may be observed if a strong or unfamiliar stimulus is presented just before, or at the same time as, the CS. This causes a reduction in the conditioned response to the CS.

Recovery from extinction

Several procedures lead to the recovery of a CR that had been first conditioned and then extinguished. This illustrates that the extinction procedure does not eliminate the effect of conditioning. These procedures are the following:

• Reacquisition: If the CS is again paired with the US, a CR is again acquired, but this second acquisition usually happens much faster than the first one.
• Spontaneous recovery: Spontaneous recovery is defined as the reappearance of a previously extinguished conditioned response after a rest period. That is, if the CS is tested at a later time (for example an hour or a day) after extinction it will again elicit a CR. This renewed CR is usually much weaker than the CR observed prior to extinction.
• Disinhibition: If the CS is tested just after extinction and an intense but associatively neutral stimulus has occurred, there may be a temporary recovery of the conditioned response to the CS.
• Reinstatement: If the US used in conditioning is presented to a subject in the same place where conditioning and extinction occurred, but without the CS being present, the CS often elicits a response when it is tested later.
• Renewal: Renewal is a reemergence of a conditioned response following extinction when an animal is returned to the environment *(or similar environment) in which the conditioned response was acquired.

Stimulus generalization

Stimulus generalization is said to occur if, after a particular CS has come to elicit a CR, a similar test stimulus is found to elicit the same CR. Usually the more similar the test stimulus is to the CS the stronger the CR will be to the test stimulus. Conversely, the more the test stimulus differs from the CS, the weaker the CR will be, or the more it will differ from that previously observed.

Stimulus discrimination

One observes stimulus discrimination when one stimulus ("CS1") elicits one CR and another stimulus ("CS2") elicits either another CR or no CR at all. This can be brought about by, for example, pairing CS1 with an effective US and presenting CS2 with no US.

Latent inhibition

Main article: Latent inhibition

Latent inhibition refers to the observation that it takes longer for a familiar stimulus to become a CS than it does for a novel stimulus to become a CS, when the stimulus is paired with an effective US.

Conditioned suppression

This is one of the most common ways to measure the strength of learning in classical conditioning. A typical example of this procedure is as follows: a rat first learns to press a lever through operant conditioning. Then, in a series of trials, the rat is exposed to a CS, a light or a noise, followed by the US, a mild electric shock. An association between the CS and US develops, and the rat slows or stops its lever pressing when the CS comes on. The rate of pressing during the CS measures the strength of classical conditioning; that is, the slower the rat presses, the stronger the association of the CS and the US. (Slow pressing indicates a "fear" conditioned response, and it is an example of a conditioned emotional response; see section below.)

Conditioned inhibition

Typically, three phases of conditioning are used.

Phase 1

A CS (CS+) is paired with a US until asymptotic CR levels are reached.

Phase 2

CS+/US trials are continued, but these are interspersed with trials on which the CS+ is paired with a second CS, (the CS-) but not with the US (i.e. CS+/CS- trials). Typically, organisms show CRs on CS+/US trials, but stop responding on CS+/CS− trials.

Phase 3

• Summation test for conditioned inhibition: The CS- from phase 2 is presented together with a new CS+ that was conditioned as in phase 1. Conditioned inhibition is found if the response is less to the CS+/CS- pair than it is to the CS+ alone.
• Retardation test for conditioned inhibition: The CS- from phase 2 is paired with the US. If conditioned inhibition has occurred, the rate of acquisition to the previous CS− should be less than the rate of acquisition that would be found without the phase 2 treatment.

Blocking

Main article: Blocking effect

This form of classical conditioning involves two phases.

Phase 1

A CS (CS1) is paired with a US.

Phase 2

A compound CS (CS1+CS2) is paired with a US.

Test

A separate test for each CS (CS1 and CS2) is performed. The blocking effect is observed in a lack of conditional response to CS2, suggesting that the first phase of training blocked the acquisition of the second CS. 

Theories

Data sources

Experiments on theoretical issues in conditioning have mostly been done on vertebrates, especially rats and pigeons. However, conditioning has also been studied in invertebrates, and very important data on the neural basis of conditioning has come from experiments on the sea slug, Aplysia. Most relevant experiments have used the classical conditioning procedure, although instrumental (operant) conditioning experiments have also been used, and the strength of classical conditioning is often measured through its operant effects, as in conditioned suppression (see Phenomena section above) and autoshaping.

Stimulus-substitution theory

Further information: Counterconditioning

According to Pavlov, conditioning does not involve the acquisition of any new behavior, but rather the tendency to respond in old ways to new stimuli. Thus, he theorized that the CS merely substitutes for the US in evoking the reflex response. This explanation is called the stimulus-substitution theory of conditioning. A critical problem with the stimulus-substitution theory is that the CR and UR are not always the same. Pavlov himself observed that a dog's saliva produced as a CR differed in composition from that produced as a UR. The CR is sometimes even the opposite of the UR. For example: the unconditional response to electric shock is an increase in heart rate, whereas a CS that has been paired with the electric shock elicits a decrease in heart rate. (However, it has been proposed that only when the UR does not involve the central nervous system are the CR and the UR opposites.)

Rescorla–Wagner model

Main article: Rescorla–Wagner model

The Rescorla–Wagner (R–W) model is a relatively simple yet powerful model of conditioning. The model predicts a number of important phenomena, but it also fails in important ways, thus leading to a number of modifications and alternative models. However, because much of the theoretical research on conditioning in the past 40 years has been instigated by this model or reactions to it, the R–W model deserves a brief description here.

The Rescorla-Wagner model argues that there is a limit to the amount of conditioning that can occur in the pairing of two stimuli. One determinant of this limit is the nature of the US. For example: pairing a bell with a juicy steak is more likely to produce salivation than pairing the bell with a piece of dry bread, and dry bread is likely to work better than a piece of cardboard. A key idea behind the R–W model is that a CS signals or predicts the US. One might say that before conditioning, the subject is surprised by the US. However, after conditioning, the subject is no longer surprised, because the CS predicts the coming of the US. (Note that the model can be described mathematically and that words like predict, surprise, and expect are only used to help explain the model.) Here the workings of the model are illustrated with brief accounts of acquisition, extinction, and blocking. The model also predicts a number of other phenomena, see main article on the model.

Equation

$${\displaystyle \mathrm{\Delta }V=\alpha \beta (\lambda -\mathrm{\Sigma }V)}$$

This is the Rescorla-Wagner equation. It specifies the amount of learning that will occur on a single pairing of a conditioning stimulus (CS) with an unconditioned stimulus (US). The above equation is solved repeatedly to predict the course of learning over many such trials.

In this model the degree of learning is measured by how well the CS predicts the US, which is given by the "associative strength" of the CS. In the equation, V represents the current associative strength of the CS, and ∆V is the change in this strength that happens on a given trial. ΣV is the sum of the strengths of all stimuli present in the situation. λ is the maximum associative strength that a given US will support; its value is usually set to 1 on trials when the US is present, and 0 when the US is absent. α and β are constants related to the salience of the CS and the speed of learning for a given US. How the equation predicts various experimental results is explained in following sections. For further details, see the main article on the model.

R–W model: acquisition

The R–W model measures conditioning by assigning an "associative strength" to the CS and other local stimuli. Before a CS is conditioned it has an associative strength of zero. Pairing the CS and the US causes a gradual increase in the associative strength of the CS. This increase is determined by the nature of the US (e.g. its intensity). The amount of learning that happens during any single CS-US pairing depends on the difference between the total associative strengths of CS and other stimuli present in the situation (ΣV in the equation), and a maximum set by the US (λ in the equation). On the first pairing of the CS and US, this difference is large and the associative strength of the CS takes a big step up. As CS-US pairings accumulate, the US becomes more predictable, and the increase in associative strength on each trial becomes smaller and smaller. Finally, the difference between the associative strength of the CS (plus any that may accrue to other stimuli) and the maximum strength reaches zero. That is, the US is fully predicted, the associative strength of the CS stops growing, and conditioning is complete.

R–W model: extinction

Comparing the associate strength by R-W model in Learning

The associative process described by the R–W model also accounts for extinction (see "procedures" above). The extinction procedure starts with a positive associative strength of the CS, which means that the CS predicts that the US will occur. On an extinction trial the US fails to occur after the CS. As a result of this "surprising" outcome, the associative strength of the CS takes a step down. Extinction is complete when the strength of the CS reaches zero; no US is predicted, and no US occurs. However, if that same CS is presented without the US but accompanied by a well-established conditioned inhibitor (CI), that is, a stimulus that predicts the absence of a US (in R-W terms, a stimulus with a negative associate strength) then R-W predicts that the CS will not undergo extinction (its V will not decrease in size).

R–W model: blocking

Main article: Blocking effect

The most important and novel contribution of the R–W model is its assumption that the conditioning of a CS depends not just on that CS alone, and its relationship to the US, but also on all other stimuli present in the conditioning situation. In particular, the model states that the US is predicted by the sum of the associative strengths of all stimuli present in the conditioning situation. Learning is controlled by the difference between this total associative strength and the strength supported by the US. When this sum of strengths reaches a maximum set by the US, conditioning ends as just described.

The R–W explanation of the blocking phenomenon illustrates one consequence of the assumption just stated. In blocking (see "phenomena" above), CS1 is paired with a US until conditioning is complete. Then on additional conditioning trials a second stimulus (CS2) appears together with CS1, and both are followed by the US. Finally CS2 is tested and shown to produce no response because learning about CS2 was "blocked" by the initial learning about CS1. The R–W model explains this by saying that after the initial conditioning, CS1 fully predicts the US. Since there is no difference between what is predicted and what happens, no new learning happens on the additional trials with CS1+CS2, hence CS2 later yields no response.

Theoretical issues and alternatives to the Rescorla–Wagner model

One of the main reasons for the importance of the R–W model is that it is relatively simple and makes clear predictions. Tests of these predictions have led to a number of important new findings and a considerably increased understanding of conditioning. Some new information has supported the theory, but much has not, and it is generally agreed that the theory is, at best, too simple. However, no single model seems to account for all the phenomena that experiments have produced. Following are brief summaries of some related theoretical issues.

Content of learning

The R–W model reduces conditioning to the association of a CS and US, and measures this with a single number, the associative strength of the CS. A number of experimental findings indicate that more is learned than this. Among these are two phenomena described earlier in this article

• Latent inhibition: If a subject is repeatedly exposed to the CS before conditioning starts, then conditioning takes longer. The R–W model cannot explain this because preexposure leaves the strength of the CS unchanged at zero.
• Recovery of responding after extinction: It appears that something remains after extinction has reduced associative strength to zero because several procedures cause responding to reappear without further conditioning.

Role of attention in learning

Latent inhibition might happen because a subject stops focusing on a CS that is seen frequently before it is paired with a US. In fact, changes in attention to the CS are at the heart of two prominent theories that try to cope with experimental results that give the R–W model difficulty. In one of these, proposed by Nicholas Mackintosh, the speed of conditioning depends on the amount of attention devoted to the CS, and this amount of attention depends in turn on how well the CS predicts the US. Pearce and Hall proposed a related model based on a different attentional principle Both models have been extensively tested, and neither explains all the experimental results. Consequently, various authors have attempted hybrid models that combine the two attentional processes. Pearce and Hall in 2010 integrated their attentional ideas and even suggested the possibility of incorporating the Rescorla-Wagner equation into an integrated model.

Context

As stated earlier, a key idea in conditioning is that the CS signals or predicts the US (see "zero contingency procedure" above). However, for example, the room in which conditioning takes place also "predicts" that the US may occur. Still, the room predicts with much less certainty than does the experimental CS itself, because the room is also there between experimental trials, when the US is absent. The role of such context is illustrated by the fact that the dogs in Pavlov's experiment would sometimes start salivating as they approached the experimental apparatus, before they saw or heard any CS. Such so-called "context" stimuli are always present, and their influence helps to account for some otherwise puzzling experimental findings. The associative strength of context stimuli can be entered into the Rescorla-Wagner equation, and they play an important role in the comparator and computational theories outlined below.

Comparator theory

To find out what has been learned, we must somehow measure behavior ("performance") in a test situation. However, as students know all too well, performance in a test situation is not always a good measure of what has been learned. As for conditioning, there is evidence that subjects in a blocking experiment do learn something about the "blocked" CS, but fail to show this learning because of the way that they are usually tested.

"Comparator" theories of conditioning are "performance based", that is, they stress what is going on at the time of the test. In particular, they look at all the stimuli that are present during testing and at how the associations acquired by these stimuli may interact. To oversimplify somewhat, comparator theories assume that during conditioning the subject acquires both CS-US and context-US associations. At the time of the test, these associations are compared, and a response to the CS occurs only if the CS-US association is stronger than the context-US association. After a CS and US are repeatedly paired in simple acquisition, the CS-US association is strong and the context-US association is relatively weak. This means that the CS elicits a strong CR. In "zero contingency" (see above), the conditioned response is weak or absent because the context-US association is about as strong as the CS-US association. Blocking and other more subtle phenomena can also be explained by comparator theories, though, again, they cannot explain everything.

Computational theory

An organism's need to predict future events is central to modern theories of conditioning. Most theories use associations between stimuli to take care of these predictions. For example: In the R–W model, the associative strength of a CS tells us how strongly that CS predicts a US. A different approach to prediction is suggested by models such as that proposed by Gallistel & Gibbon (2000, 2002). Here the response is not determined by associative strengths. Instead, the organism records the times of onset and offset of CSs and USs and uses these to calculate the probability that the US will follow the CS. A number of experiments have shown that humans and animals can learn to time events (see Animal cognition), and the Gallistel & Gibbon model yields very good quantitative fits to a variety of experimental data. However, recent studies have suggested that duration-based models cannot account for some empirical findings as well as associative models.

Element-based models

The Rescorla-Wagner model treats a stimulus as a single entity, and it represents the associative strength of a stimulus with one number, with no record of how that number was reached. As noted above, this makes it hard for the model to account for a number of experimental results. More flexibility is provided by assuming that a stimulus is internally represented by a collection of elements, each of which may change from one associative state to another. For example, the similarity of one stimulus to another may be represented by saying that the two stimuli share elements in common. These shared elements help to account for stimulus generalization and other phenomena that may depend upon generalization. Also, different elements within the same set may have different associations, and their activations and associations may change at different times and at different rates. This allows element-based models to handle some otherwise inexplicable results.

The SOP model

A prominent example of the element approach is the "SOP" model of Wagner. The model has been elaborated in various ways since its introduction, and it can now account in principle for a very wide variety of experimental findings. The model represents any given stimulus with a large collection of elements. The time of presentation of various stimuli, the state of their elements, and the interactions between the elements, all determine the course of associative processes and the behaviors observed during conditioning experiments.

The SOP account of simple conditioning exemplifies some essentials of the SOP model. To begin with, the model assumes that the CS and US are each represented by a large group of elements. Each of these stimulus elements can be in one of three states:

• primary activity (A1) - Roughly speaking, the stimulus is "attended to." (References to "attention" are intended only to aid understanding and are not part of the model.)
• secondary activity (A2) - The stimulus is "peripherally attended to."
• inactive (I) – The stimulus is "not attended to."

Of the elements that represent a single stimulus at a given moment, some may be in state A1, some in state A2, and some in state I.

When a stimulus first appears, some of its elements jump from inactivity I to primary activity A1. From the A1 state they gradually decay to A2, and finally back to I. Element activity can only change in this way; in particular, elements in A2 cannot go directly back to A1. If the elements of both the CS and the US are in the A1 state at the same time, an association is learned between the two stimuli. This means that if, at a later time, the CS is presented ahead of the US, and some CS elements enter A1, these elements will activate some US elements. However, US elements activated indirectly in this way only get boosted to the A2 state. (This can be thought of the CS arousing a memory of the US, which will not be as strong as the real thing.) With repeated CS-US trials, more and more elements are associated, and more and more US elements go to A2 when the CS comes on. This gradually leaves fewer and fewer US elements that can enter A1 when the US itself appears. In consequence, learning slows down and approaches a limit. One might say that the US is "fully predicted" or "not surprising" because almost all of its elements can only enter A2 when the CS comes on, leaving few to form new associations.

The model can explain the findings that are accounted for by the Rescorla-Wagner model and a number of additional findings as well. For example, unlike most other models, SOP takes time into account. The rise and decay of element activation enables the model to explain time-dependent effects such as the fact that conditioning is strongest when the CS comes just before the US, and that when the CS comes after the US ("backward conditioning") the result is often an inhibitory CS. Many other more subtle phenomena are explained as well.

A number of other powerful models have appeared in recent years which incorporate element representations. These often include the assumption that associations involve a network of connections between "nodes" that represent stimuli, responses, and perhaps one or more "hidden" layers of intermediate interconnections. Such models make contact with a current explosion of research on neural networks, artificial intelligence and machine learning.

Applications

Neural basis of learning and memory

Pavlov proposed that conditioning involved a connection between brain centers for conditioned and unconditioned stimuli. His physiological account of conditioning has been abandoned, but classical conditioning continues to be used to study the neural structures and functions that underlie learning and memory. Forms of classical conditioning that are used for this purpose include, among others, fear conditioning, eyeblink conditioning, and the foot contraction conditioning of Hermissenda crassicornis, a sea-slug. Both fear and eyeblink conditioning involve a neutral stimulus, frequently a tone, becoming paired with an unconditioned stimulus. In the case of eyeblink conditioning, the US is an air-puff, while in fear conditioning the US is threatening or aversive such as a foot shock.

"Available data demonstrate that discrete regions of the cerebellum and associated brainstem areas contain neurons that alter their activity during conditioning – these regions are critical for the acquisition and performance of this simple learning task. It appears that other regions of the brain, including the hippocampus, amygdala, and prefrontal cortex, contribute to the conditioning process, especially when the demands of the task get more complex."

Fear and eyeblink conditioning involve generally non overlapping neural circuitry, but share molecular mechanisms. Fear conditioning occurs in the basolateral amygdala, which receives glutaminergic input directly from thalamic afferents, as well as indirectly from prefrontal projections. The direct projections are sufficient for delay conditioning, but in the case of trace conditioning, where the CS needs to be internally represented despite a lack of external stimulus, indirect pathways are necessary. The anterior cingulate is one candidate for intermediate trace conditioning, but the hippocampus may also play a major role. Presynaptic activation of protein kinase A and postsynaptic activation of NMDA receptors and its signal transduction pathway are necessary for conditioning related plasticity. CREB is also necessary for conditioning related plasticity, and it may induce downstream synthesis of proteins necessary for this to occur. As NMDA receptors are only activated after an increase in presynaptic calcium(thereby releasing the Mg2+ block), they are a potential coincidence detector that could mediate spike timing dependent plasticity. STDP constrains LTP to situations where the CS predicts the US, and LTD to the reverse.

Behavioral therapies

Main article: Behavior therapy

Some therapies associated with classical conditioning are aversion therapy, systematic desensitization and flooding. Aversion therapy is a type of behavior therapy designed to make patients cease an undesirable habit by associating the habit with a strong unpleasant unconditioned stimulus. For example, a medication might be used to associate the taste of alcohol with stomach upset. Systematic desensitization is a treatment for phobias in which the patient is trained to relax while being exposed to progressively more anxiety-provoking stimuli (e.g. angry words). This is an example of counterconditioning, intended to associate the feared stimuli with a response (relaxation) that is incompatible with anxiety Flooding is a form of desensitization that attempts to eliminate phobias and anxieties by repeated exposure to highly distressing stimuli until the lack of reinforcement of the anxiety response causes its extinction. "Flooding" usually involves actual exposure to the stimuli, whereas the term "implosion" refers to imagined exposure, but the two terms are sometimes used synonymously.

Conditioning therapies usually take less time than humanistic therapies.

Conditioned drug response

A stimulus that is present when a drug is administered or consumed may eventually evoke a conditioned physiological response that mimics the effect of the drug. This is sometimes the case with caffeine; habitual coffee drinkers may find that the smell of coffee gives them a feeling of alertness. In other cases, the conditioned response is a compensatory reaction that tends to offset the effects of the drug. For example, if a drug causes the body to become less sensitive to pain, the compensatory conditioned reaction may be one that makes the user more sensitive to pain. This compensatory reaction may contribute to drug tolerance. If so, a drug user may increase the amount of drug consumed in order to feel its effects, and end up taking very large amounts of the drug. In this case a dangerous overdose reaction may occur if the CS happens to be absent, so that the conditioned compensatory effect fails to occur. For example, if the drug has always been administered in the same room, the stimuli provided by that room may produce a conditioned compensatory effect; then an overdose reaction may happen if the drug is administered in a different location where the conditioned stimuli are absent.

Conditioned hunger

Signals that consistently precede food intake can become conditioned stimuli for a set of bodily responses that prepares the body for food and digestion. These reflexive responses include the secretion of digestive juices into the stomach and the secretion of certain hormones into the blood stream, and they induce a state of hunger. An example of conditioned hunger is the "appetizer effect." Any signal that consistently precedes a meal, such as a clock indicating that it is time for dinner, can cause people to feel hungrier than before the signal. The lateral hypothalamus (LH) is involved in the initiation of eating. The nigrostriatal pathway, which includes the substantia nigra, the lateral hypothalamus, and the basal ganglia have been shown to be involved in hunger motivation.

Conditioned emotional response

Further information: Conditioned emotional response and Fear conditioning

The influence of classical conditioning can be seen in emotional responses such as phobia, disgust, nausea, anger, and sexual arousal. A familiar example is conditioned nausea, in which the CS is the sight or smell of a particular food that in the past has resulted in an unconditioned stomach upset. Similarly, when the CS is the sight of a dog and the US is the pain of being bitten, the result may be a conditioned fear of dogs. An example of conditioned emotional response is conditioned suppression.

As an adaptive mechanism, emotional conditioning helps shield an individual from harm or prepare it for important biological events such as sexual activity. Thus, a stimulus that has occurred before sexual interaction comes to cause sexual arousal, which prepares the individual for sexual contact. For example, sexual arousal has been conditioned in human subjects by pairing a stimulus like a picture of a jar of pennies with views of an erotic film clip. Similar experiments involving blue gourami fish and domesticated quail have shown that such conditioning can increase the number of offspring. These results suggest that conditioning techniques might help to increase fertility rates in infertile individuals and endangered species.

Pavlovian-instrumental transfer

Main article: Pavlovian-instrumental transfer

Pavlovian-instrumental transfer is a phenomenon that occurs when a conditioned stimulus (CS, also known as a "cue") that has been associated with rewarding or aversive stimuli via classical conditioning alters motivational salience and operant behavior. In a typical experiment, a rat is presented with sound-food pairings (classical conditioning). Separately, the rat learns to press a lever to get food (operant conditioning). Test sessions now show that the rat presses the lever faster in the presence of the sound than in silence, although the sound has never been associated with lever pressing.

Pavlovian-instrumental transfer is suggested to play a role in the differential outcomes effect, a procedure which enhances operant discrimination by pairing stimuli with specific outcomes.

Self-enhancement

From Wikipedia, the free encyclopedia

https://en.wikipedia.org/wiki/Self-enhancement 

Self-enhancement is a type of motivation that works to make people feel good about themselves and to maintain self-esteem. This motive becomes especially prominent in situations of threat, failure or blows to one's self-esteem. Self-enhancement involves a preference for positive over negative self-views. It is one of the three self-evaluation motives along with self-assessment (the drive for an accurate self-concept) and self-verification (the drive for a self-concept congruent with one's identity). Self-evaluation motives drive the process of self-regulation, that is, how people control and direct their own actions.

There are a variety of strategies that people can use to enhance their sense of personal worth. For example, they can downplay skills that they lack or they can criticise others to seem better by comparison. These strategies are successful, in that people tend to think of themselves as having more positive qualities and fewer negative qualities than others. Although self-enhancement is seen in people with low self-esteem as well as with high self-esteem, these two groups tend to use different strategies. People who already have high esteem enhance their self-concept directly, by processing new information in a biased way. People with low self-esteem use more indirect strategies, for example by avoiding situations in which their negative qualities will be noticeable.

There are controversies over whether or not self-enhancement is beneficial to the individual, and over whether self-enhancement is culturally universal or specific to Western individualism.

Levels

Self-enhancement can occur in many different situations and under many different guises. The general motive of self-enhancement can have many differing underlying explanations, each of which becomes more or less dominant depending on the situation.

The explanations of the self-enhancement motive can occur in different combinations. Self-enhancement can occur as an underlying motive or personality trait without occurring as an observed effect.

Levels of self-enhancement

Observed effect	Self-enhancement at the level of an observed effect describes the product of the motive. For example, self-enhancement can produce inflated self-ratings (positive illusions). Such ratings would be self-enhancement manifested as an observed effect. It is an observable instance of the motive.
Ongoing process	Self-enhancement at the level of an ongoing process describes the actual operation of the motive. For example, self-enhancement can result in attributing favourable outcomes to the self and unfavourable outcomes to others (self-serving attribution bias). The actual act of attributing such ratings would be self-enhancement manifested as an ongoing process. It is the motive in operation.
Personality trait	Self-enhancement at the level of a personality trait describes habitual or inadvertent self-enhancement. For example, self-enhancement can cause situations to be created to ease the pain of failure (self-handicapping). The fabrication of such situations or excuses frequently and without awareness would be self-enhancement manifested as a personality trait. It is the repetitive inclination to demonstrate the motive.
Underlying motive	Self-enhancement at the level of an underlying motive describes the conscious desire to self-enhance. For example, self-enhancement can cause the comparison of the self to a worse other, making the self seem greater in comparison (strategic social comparisons). The act of comparing intentionally to achieve superiority would be self-enhancement manifested as an underlying motive. It is the genuine desire to see the self as superior.
The four levels of self-enhancement manifestation as defined by Sedikides & Gregg (2008)

Dimensions

Both the extent and the type of self-enhancement vary across a number of dimensions.

Self-advancement vs. self-protection

Self-enhancement can occur by either self-advancing or self-protecting, that is either by enhancing the positivity of one's self-concept, or by reducing the negativity of one's self-concept. Self-protection appears to be the stronger of the two motives, given that avoiding negativity is of greater importance than encouraging positivity. However, as with all motivations, there are differences between individuals. For example, people with higher self-esteem appear to favour self-advancement, whereas people with lower self-esteem tend to self-protect. This highlights the role of risk: to not defend oneself against negativity in favour of self-promotion offers the potential for losses, whereas whilst one may not gain outright from self-protection, one does not incur the negativity either. People high in self-esteem tend to be greater risk takers and therefore opt for the more risky strategy of self-advancement, whereas those low in self-esteem and risk-taking hedge their bets with self-protection.

Public vs. private

Self-enhancement can occur in private or in public. Public self-enhancement is obvious positive self-presentation, whereas private self enhancement is unnoticeable except to the individual. The presence of other people i.e. in public self-enhancement, can either augment or inhibit self-enhancement. Whilst self-enhancement may not always take place in public it is nevertheless still influenced by the social world, for example via social comparisons.

Central vs. peripheral

Potential areas of self-enhancement differ in terms how important, or central, they are to a person. Self-enhancement tends to occur more in the domains that are the most important to a person, and less in more peripheral, less important domains.

Candid vs. tactical

Self-enhancement can occur either candidly or tactically. Candid self-enhancement serves the purpose of immediate gratification whereas tactical self-enhancement can result in potentially larger benefits from delayed gratification.

Tactical self-enhancement is often preferred over candid self-enhancement as overt self-enhancement is socially displeasing for those around it. Narcissism is an exemplification of extreme candid self-enhancement.

Types

Self-enhancement does not just occur at random. Its incidence is often highly systematic and can occur in any number of ways in order to achieve its goal of inflating perceptions of the self. Importantly, we are typically unaware that we are self-enhancing. Awareness of self-enhancing processes would highlight the facade we are trying to create, revealing that the self we perceive is in fact an enhanced version of our actual self.

Self-serving attribution bias

Main article: Self-serving bias

Self-enhancement can also affect the causal explanations people generate for social outcomes. People have a tendency to exhibit a self-serving attribution bias, that is to attribute positive outcomes to one's internal disposition but negative outcomes to factors beyond one's control e.g. others, chance or circumstance. In short, people claim credit for their successes but deny responsibilities for their failures. The self-serving attribution bias is very robust, occurring in public as well as in private, even when a premium is placed on honesty. People most commonly manifest a self-serving bias when they explain the origin or events in which they personally had a hand or a stake.

Explanations for moral transgressions follow similar self-serving patterns, as do explanations for group behaviour. The ultimate attribution error is the tendency to regard negative acts by one's out-group and positive acts by one's in-group as essential to their nature i.e. attributable to their internal disposition and not a product of external factors. This may reflect the operation of the self-serving bias refracted through social identification.

Selectivity

Selective memory

Main article: Mnemic neglect

 

Selectivity within information processing

Selective attention	People typically avoid attending to negative, unflattering information at encoding, therefore its initial recognition is impaired. Selective attention manifests itself in the form of an overt behaviour via selective exposure.
Selective exposure	People selectively expose themselves to information that justifies important prior decisions they have made. This holds true so long as the information appears to be valid and the decision that was made was done so freely and is irreversible.
Selective recall	At retrieval people bring to mind a highly biased collection of memories. Selective recall occurs for behaviours that exemplify desirable personality traits, harmonious interpersonal relationships or even health enhancing habits. Affect associated with unpleasant memories also fades faster than affect associated with pleasant memories.

People sometimes self-enhance by selectively remembering their strengths rather than weaknesses. This pattern of selective forgetting has been described as mnemic neglect. Mnemic neglect may reflect biases in the processing of information at either encoding, retrieval or retention.

• Biases at encoding occur via selective attention and selective exposure.
• Biases at retrieval and retention occur via selective recall.

The role of mnemic neglect can be emphasised or reduced by the characteristics of a certain behaviour or trait. For example, after receiving false feedback pertaining to a variety of behaviours, participants recalled more positive behaviours than negative ones, but only when the behaviours exemplified central not peripheral traits and only when feedback pertained to the self and not to others. Similar findings emerge when the to-be-recalled information is personality traits, relationship promoting or undermining behaviours, frequencies of social acts, and autobiographical memories.

Selective acceptance and refutation

Selective acceptance involves taking as fact self-flattering or ego-enhancing information with little regard for its validity. Selective refutation involves searching for plausible theories that enable criticism to be discredited. A good example of selective acceptance and refutation in action would be: Selective acceptance is the act of accepting as valid an examination on which one has performed well without consideration of alternatives, whereas selective refutation would be mindfully searching for reasons to reject as invalid an examination on which one has performed poorly.

Concordant with selective acceptance and refutation is the observation that people hold a more critical attitude towards blame placed upon them, but a more lenient attitude to praise that they receive. People will strongly contest uncongenial information but readily accept at without question congenial information.

Strategies

Strategic social comparisons

The potential directions for strategic social comparisons.

The social nature of the world we live in means that self-evaluation cannot take place in an absolute nature – comparison to other social beings is inevitable. Many social comparisons occur automatically as a consequence of circumstance, for example within an exam sitting social comparisons of intellect may occur to those sitting the same exam. However, the strength of the self-enhancement motive can cause the subjective exploitation of scenarios in order to give a more favourable outcome to the self in comparisons between the self and others. Such involuntary social comparisons prompt self-regulatory strategies.

Self-esteem moderates the beneficial, evaluative consequences of comparisons to both inferior and superior others. People with higher self-esteem are more optimistic about both evading the failures and misfortunes of their inferiors and about securing the successes and good fortunes of their superiors.

Upward social comparisons

An upwards social comparison involves comparing oneself to an individual perceived to be superior to or better than oneself. Upwards social comparison towards someone felt to be similar to oneself can induce self-enhancement through assimilation of the self and other's characteristics, however this only occurs when:

• The gap between the self and the comparison target is not too large;
• The skill or success being compared is attainable;
• The comparison target is perceived as a competitor.

Where assimilation does not occur as a result of a social comparison, contrast can instead occur which can lead to upwards social comparisons providing inspiration.

Downward social comparisons

Even though upwards social comparisons are the most common social comparisons, people do sometimes make downwards social comparisons. Downwards social comparisons involve comparing oneself to an individual perceived to be inferior to or less skilled than the self. Downwards social comparisons serve as a form of ego-defence whereby the ego is inflated due to the sense of superiority gained from such downwards social comparisons.

Lateral social comparisons

Lateral social comparisons, comparisons against those perceived as equal to the self, can also be self-enhancing. Comparisons with members of one's in-group can lead be protective against low self-esteem, especially when the in-group are disadvantaged.

Self-evaluation maintenance theory

Main article: Self-evaluation maintenance theory

Self-enhancement waxes and wanes as a function of one's ability level in the context of interpersonal relationships, and this, in turn influences interpersonal attitudes and behaviours. Three factors influence the self-evaluations people make:

• Closeness of a relationship: comparison of one's own performance with that of another is more likely to occur, and when it does is more consequential when others are close rather than distant.
• Personal relevance of a particular ability: when the domain is not relevant to oneself reflection will occur and when the domain is relevant comparison will occur.
  • Reflection: one will undergo self-enhancement (pride) when the other does well, but self-derogation (shame) when the other does poorly.
  • Comparison: one will undergo self-derogation (humiliation) if others perform well, but self-enhancement (triumph) if the other performs poorly.
• Level of performance in that ability domain.

People adopt a variety of coping strategies to deal with the pressures of self-evaluation:

• Choose friends and partners who excel, but not in the same domains as they do;
• Withhold information that is likely to improve the performance of others of personally relevant domains;
• Alter the relevance of performance domains by changing their self-concept, thus moderating the impact of the reflection and comparison processes;
• Broaden or narrow the gap between the oneself and others, even by deliberately altering the difficulty of domain-relevant tasks.

Strategic construal

The concepts that people use to understand themselves and their social world are relatively vague. Consequently, when making social comparisons or estimations people can easily and subtly shift their construal of the meaning of those concepts in order to self-enhance. Strategic construals typically increase following negative feedback. Numerous examples of strategic construals exist, a small selection include:

• People's interpretation of what counts as a virtue or talent is biased in favour of the attributes they possess, and of what counts as a vice or deficiency in favour of attributes they lack.
• People rate personality feedback and scientific research as less credible if it implies they are susceptible to disease.
• Lazy people perceive the rest of the world as reasonably fit and healthy, whereas frequent exercisers see their athleticism as a single, unique attribute.
• Low achievers in a particular area are likely to perceive the successes of high achievers as exceptional, thereby lessening the shame of their own inability.
• People think harder about any discouraging test results they receive, will spend longer thinking about them, are more inclined to have them confirmed and are significantly more skeptical of them. People do not react the same way to test results received by others however.
• When research tarnishes the reputation of groups with which people identify, they search for a statistical weakness of that research.
• Strategic construals can also be more subtle. People make self-aggrandizing interpretations not only of their own attributes, but also of others in order to appear greater by comparison.

Strategic construals appear to operate around one's self-esteem. After either positive or negative feedback people with high self-esteem alter their perceptions of others, typically varying their perceptions of others ability and performance in a self-enhancing direction. Those with low self-esteem however do not. Self-esteem level appears to moderate the use of strategic construals. As well as operating as a function of self-esteem level, strategic construals also appear to protect self-esteem levels. For example, members of minority groups who perform poorly in academic settings due to negative cultural attitudes towards them, subsequently disengage psychologically from, and dissidentify with academic pursuits in general. Whilst buffering their self-esteem level they jeopardise their future socioeconomic prospects.

Strategic construals also influence the degree to which categories are believed to characterise other people. There is a general tendency to assume that others share one's own characteristics. Nevertheless, people reliably overestimate the prevalence of their shortcomings e.g. show enhanced false consensus effect, and underestimate the prevalence of their strengths e.g. show a contrary false uniqueness effect. People perceive their flaws as relatively commonplace but their skills as unique.

Behavioural self-handicapping

Main article: Self-handicapping

Behavioural self-handicapping is the act of erecting obstacles in the path of task success in order to reduce the evaluative implications that can be drawn from task performance. This permits self-enhancement to occur in two ways:

• In the case of failure, self-handicapping can protect self-esteem by attributing failure to obstacles that one has erected – discounting.
• In the case of success, self-handicapping can promote self-esteem by attributing success to oneself despite the obstacles one has erected – augmenting.

People low in self-esteem opt for discounting as a self-protective route to avoid being perceived as incompetent, whereas people high in self-esteem preferentially select augmenting as a method of self-promotion to enhance their perceived competence. Self-handicapping, whilst predominantly a behaviour that occurs in private performance is magnified in public situations. However, self-handicapping is highly risky in social situations. If found out, those who use it face the negative evaluation and criticism of others.

Factors promoting behavioural self-handicapping
Task familiarity	Uncertainty over ability to obtain a positive outcome due to experience of limited control over a similar task.
Task complexity	Holding a very fixed, concrete theory of the complexity of a task.
Insecurity	Uncertainty over ability to obtain a positive outcome due to generally insecure sense of self.
Belief	Holding the belief that improvement is physically possible.
Importance	A task or evaluation has to be important to the self in order for self-handicapping to occur.
Feedback	Negative feedback makes self-handicapping more probable as it allows any damage to the ego to be rectified.
Neuroticism	High neuroticism promotes discounting.
Conscientiousness	Low conscientiousness can increase the tendency to self-handicap.

Regardless of the causes of self-handicapping the self-defeating end result remains the same – the integrity and quality of a task outcome or evaluation is compromised in order that the meaning of that outcome appears more agreeable. Behavioural self-handicapping is a good demonstration of active self-deception.

Whilst task performance is important to people, they do sometimes act in ways so as to paradoxically impair task performance, either to protect against the shame of performing poorly by creating a convenient excuse (discounting), or to enhance themselves by succeeding despite adversity by creating grounds for conceit (augmenting). Furthermore, self-handicapping can have unintentional adverse consequences. Whilst allowing the maintenance of positive self-views self-handicapping has the cost of impairing objective performance. Students who report frequent use self-handicapping strategies underperform relative to their aptitude, with poor examination preparation mediating the effect.

Ultimately, those who readily prepare themselves for the possibility of poor task performance beforehand use the strategy of discounting less.

Outcomes

The effect of self-enhancement strategies is shown in the tendency of people to see themselves as having more positive qualities and a more positive future outlook than others.

Self-enhancing triad

Main article: Positive illusions

People generally hold unrealistically positive views about themselves. Such flattering views can often be neatly categorised within what has become known as the Triad of Positive Illusions. The three illusions in question are above-average effect, illusions of control, and unrealistic optimism. These illusions can be replicated across many situations and are highly resistant to revision. Rather ironically, when informed of the existence of such illusions, people generally consider themselves to be less prone to them than others.

Above-average effect

Main article: Illusory superiority

The better-than-average-effect is the most common demonstration of an above-average effect. It is a highly robust effect, as evidenced by the fact that even when the criteria on which the self and others are judged are identical the self is still perceived more favourably. Things close to the self also take on the perceived superiority of the above-average effect. People value both their close relationships and their personal possessions above those of others. However, where an outcome is perceived as highly skilled, people often err on the side of caution and display a worse-than-average effect. The majority of people would rate themselves as below average in unicycling ability, for example.

The three related divisions of the self-enhancing triad.

The illusory nature of the above-average effect comes from the fact that not everyone can be above-average – otherwise the average would not be the average! The majority of people rating themselves as being better than the majority of people does not quite seem plausible, and in some situations is 100% impossible. Where a distribution is symmetrical i.e. mean = median = mode, it is statistically impossible for the majority of people to be above average, as whichever of the three averages is taken, all are equal to the 50th percentile. In a non-symmetrical distribution i.e. mean < median < mode or mode < median < mean, it is statistically impossible for the majority of people to be above average when the average is taken to be the median, as the median represents the 50th percentile, or the midpoint of the data. However, in a non-symmetrical distribution where the average is taken to be either the mean or the mode, the above-average effect can be statistically plausible. In some situations the majority of people can be above-average.

People show self-enhancement in the form of the above-average effect in many different ways. It is typical for people to profess to be above-average at a task yielding positive or desirable outcomes, and below average at a task yielding negative or undesirable outcomes.

Some of the wide variety of documented examples of the above-average effect include observations that:

• Most university students regard themselves as well above the 50th percentile in exhibiting social grace, athletic prowess and leadership abilities.
• Even 12th percentile achievers in domains such as grammar and logic consider themselves to be of 62nd percentile achievement.
• 94% of university professors believe their teaching ability to be above average.
• University students in the UK and the US regard themselves as above average drivers. Even drivers hospitalised after causing accidents persist in believing they are no worse than regular drivers.
• Even when informed about the above average effect people rate themselves as less susceptible to such biases than others.

Illusions of control

Main article: Illusion of control

People overestimate the level of control they have over outcomes and contingencies, seeing their actions as influential even when they are in fact inconsequential. Also, people stand by their apparent conviction that they can influence the outcomes of inherently random systems for example lotteries, especially when such systems possess features typically associated with skill-based tasks. Even when a degree of contingency does exist between actions and outcomes, people still reliably overestimate the strength of that contingency.

Unrealistic optimism

Main article: Optimism bias

People typically believe that their life will hold a greater number of positive experiences and fewer negative experiences than the lives of similar others. They have the same unrealistic optimism, but to a lesser degree, for others who are closely linked, such as romantic partners and close personal friends.

Unrealistic optimism is apparent in people's behaviours and beliefs across many different situations. People can both overestimate their ability to predict the future, and underestimate how long it will take them to complete a variety of tasks. People also overestimate the accuracy of their social predictions, and interpret probability adverbs to award higher values for personal positive outcomes and lower values for personal negative outcomes. Smokers, rather alarmingly, underestimate their risk of cancer relative to both non-smokers and even in comparison with fellow smokers.

Benefits and costs to the individual

There is controversy over whether self-enhancement is adaptive or maladaptive. A single operationalisation of self-enhancement can be influenced by a variety of motives and thus can be coordinated with both positive and negative outcomes. Those who misperceive their performance (self-enhancers and self-effacers) tend to have a lower academic achievement, lower subsequent performance. These results appear to be culturally universal. Surely, it's a false assumption to relate self enhancement to depression.

• If self-enhancement is taken to mean rendering more positive judgments of oneself than of others then outcomes are frequently favourable.
• If self-enhancement is taken to mean the rendering of more positive judgements of oneself than others render then outcomes are often untoward.

Which definition is better at measuring self-enhancement has been disputed, as rating oneself more positively than one rates others is not seen as self-enhancement by some researchers.

In some studies, self-enhancement has been shown to have strong positive links with good mental health and in others with bad mental health. Self-enhancing can also have social costs. Whilst promoting resilience amongst survivors of the September 11th terrorist attacks, those who self-enhanced were rated as having decreased social adaptation and honesty by friends and family.

Constraints

Plausibility

Self-enhancement thrives upon the vagueness or ambiguity of evidence. Where criteria are rigidly defined, self-enhancement typically reduces. For example, the above-average effect decreases as clarity and definition of the defined trait increases. The easier it is to verify a behaviour or trait, the less that trait will be subject to self-enhancement. The plausibility of a trait or characteristic given real world evidence moderates the degree to which the self-enhancement of that trait occurs. Selectively recalling instances of desirable traits is moderated by one's actual standing on those traits in reality.

When plausibility reduces the impact of self-enhancement, undesirable evidence often has to be accepted, albeit reluctantly. This typically occurs when all possible interpretations of the evidence in question have been made. The reason for this unwilling acceptance is to maintain effective social functioning, where unqualified self-aggrandizement would otherwise prevent it. People will continue to self-enhance so long as they think they can get away with it.

The constraint of plausibility on self enhancement exists because self-enhancing biases cannot be exploited. Self-enhancement works only under the assumption of rationality – to admit to self-enhancing totally undermines any conclusions one can draw and any possibility of believing its facade, since according to legit rational processes it functions as a genuinely verifiable and accredited improvement.

Mood

Both positive and negative moods can reduce the presence of the self-enhancement motive. The effects of mood on self-enhancement can be explained by a negative mood making the use self-enhancing tactics harder, and a positive mood making their use less necessary in the first place.

The onset of a positive mood can make people more receptive to negative diagnostic feedback. Past successes are reviewed with expectation of receiving such positive feedback, presumably to buffer their mood.

Depression has quite a well-evidenced link with a decrease in the motive to self-enhance. Depressives are less able to self-enhance in response to negative feedback than non-depressive controls. Having a depressive disposition decreases the discrepancy between one's own estimates of one's virtues and the estimates of a neutral observer, namely by increasing modesty. Illusions of control are moderated by melancholy. However, whilst the self-ratings of depressives are more in line with those of neutral observers than the self ratings of normals, the self ratings of normals are more in line with those of friends and family than the self ratings of depressives.

Social context and relationships

The presence of the motive to self-enhance is dependent on many social situations, and the relationships shared with the people in them. Many different materialisations of self-enhancement can occur depending on such social contexts:

• The self-enhancement motive is weaker during interactions with close and significant others.
• When friends (or previous strangers whose intimacy levels have been enhanced) cooperate on a task, they do not exhibit a self-serving attribution bias.
  • Casual acquaintances and true strangers however do exhibit a self-serving attribution bias.
  • Where no self-serving bias is exhibited in a relationship, a betrayal of trust in the relationship will reinstate the self-serving bias. This corresponds to findings that relationship satisfaction is inversely correlated with the betrayal of trust.
• Both mutual liking and expectation of reciprocity appear to mediate graciousness in the presence of others.
• Whilst people have a tendency to self-present boastfully in front of strangers, this inclination disappears in the presence of friends.
• Others close to the self are generally more highly evaluated than more distant others.

Culture

Psychological functioning is moderated by the influence of culture. There is much evidence to support a culture-specific view of self-enhancement.

Westerners typically...	Easterners typically...
Prioritise intradependence	Prioritise interdependence
Place greater importance on individualistic values	Place greater importance on collectivistic values
Have more inflated ratings of their own merits	Have less inflated ratings of their own merits
Emphasise internal attributes	Emphasise relational attributes
Show self-enhancement that overshadows self-criticism	Show self-criticism that overshadows self-enhancement
Give spontaneously more positive self-descriptions	Give spontaneously more negative self-descriptions
Make fewer self-deprecatory social comparisons	Make more self-deprecatory social comparisons
Hold more unrealistically optimistic views of the future	Hold fewer unrealistically optimistic views of the future
Display a self-serving attributional bias	Do not display a self-serving attributional bias
Show a weak desire to self-improve via self-criticism	Show a strong desire to self-improve via self-criticism
Are eager to conclude better performance than a classmate	Are reluctant to conclude better performance than a classmate
Reflexively discount negative feedback	Readily acknowledge negative feedback
Persist more after initial success	Persist more after initial failure
Consider tasks in which they succeed to be most diagnostic	Consider tasks in which they fail to be most diagnostic
Self-enhance on the majority of personality dimensions	Self-enhance only on some personality dimensions
Self-enhance on individualistic attributes	Self-enhance on collectivist attributes

Self-enhancement appears to be a phenomenon largely limited to Western cultures, where social ties are looser than in the East. This is concordant with empirical evidence highlighting relationship closeness as a constraint on self-enhancement. The self-improvement motive, as an aspiration towards a possible self may also moderate a variety of psychological processes in both independent and interdependent cultures.

There are nevertheless signs that self-enhancement is not completely absent in interdependent cultures. Chinese schoolchildren rate themselves highly on the dimension of competence, and Taiwanese employees rate themselves more favourably than their employers do, both of which show self-enhancing tendencies in Eastern cultures.

One possible explanation for the observed differences in self-enhancement between cultures is that they may occur through differences in how candidly of tactically the motive to self-enhance is acted upon, and not due to variations in the strength of motive. Alternatively, self-enhancement may be represented only in terms of the characteristics that are deemed important by individuals as they strive to fulfil their culturally prescribed roles.

The issue over whether self-enhancement is universal or specific to Western cultures has been contested within modern literature by two researchers — Constantine Sedikides and Steven Heine. Sedikides argues that self-enhancement is universal, and that different cultures self-enhance in domains important in their culture. Heine on the other hand describes self-enhancement as a predominantly Western motive.

Other motives

It is an exaggeration to say that self-enhancement is the dominant self-evaluation motive. Many controversies exist regarding the distinction between the self-evaluation motives, and there are situations in which motives asides from self-enhancement assume priority.

1. The self-assessment motive is often contrasted with the self-enhancement motive due to the relative adaptiveness of each approach within social interactions.
2. The self-verification motive is often challenged by supporters of the self-enhancement as being unfeasible as it often appears implausible.
3. The self-improvement motive is often taken to be the physical manifestation of the self-enhancement motive i.e. the act of attaining desired positive self views.

Where the truth about oneself worsens or varies it gradually becomes less feasible to satisfy all motives simultaneously.

In an attempt to compare the self-evaluation motives (excluding self-improvement) a self-reflection task was employed. Participants were asked to choose the question they would most likely ask themselves in order to determine whether they possessed a certain personality trait. On the whole, people self-enhanced more than they self-assessed or self-verified. People chose higher diagnosticity questions concerning central, positive traits than central, negative ones, and answered yes more often to central, positive than negative questions. Also, people self-verified more than the self-assessed, and chose more questions overall concerning relatively certain central traits than relatively uncertain peripheral traits.

Other factors

• Cognitive load: Where people are in situations of great cognitive load, the tendency to self-enhance increases, almost as if instinctive. People are quicker to agree with possessing positive traits and slower to reject having negative traits.
• Modifiability: Where a trait or characteristic is seen as unchangeable people are more self-enhancing versus perceiving the trait to be modifiable.
• Diagnosticity: Where a trait or characteristic is seen as highly diagnostic people are less likely to self-enhance, for fear of being caught out in the process of an erroneous attempt at self enhancement as neurosis.

Defence mechanism

From Wikipedia, the free encyclopedia

https://en.wikipedia.org/wiki/Defence_mechanism 

 

In psychoanalytic theory, a defence mechanism (American English: defense mechanism), is an unconscious psychological operation that functions to protect a person from anxiety-producing thoughts and feelings related to internal conflicts and outer stressors.

Defence mechanisms may result in healthy or unhealthy consequences depending on the circumstances and frequency with which the mechanism is used. Defence mechanisms (German: Abwehrmechanismen) are psychological strategies brought into play by the unconscious mind to manipulate, deny, or distort reality in order to defend against feelings of anxiety and unacceptable impulses and to maintain one's self-schema or other schemas. These processes that manipulate, deny, or distort reality may include the following: repression, or the burying of a painful feeling or thought from one's awareness even though it may resurface in a symbolic form; identification, incorporating an object or thought into oneself; and rationalization, the justification of one's behaviour and motivations by substituting "good" acceptable reasons for the actual motivations. In psychoanalytic theory, repression is considered the basis for other defence mechanisms.

Healthy people normally use different defence mechanisms throughout life. A defence mechanism becomes pathological only when its persistent use leads to maladaptive behaviour such that the physical or mental health of the individual is adversely affected. Among the purposes of ego defence mechanisms is to protect the mind/self/ego from anxiety or social sanctions or to provide a refuge from a situation with which one cannot currently cope.

One resource used to evaluate these mechanisms is the Defense Style Questionnaire (DSQ-40).

Theories and classifications

Different theorists have different categorizations and conceptualizations of defence mechanisms. Large reviews of theories of defence mechanisms are available from Paulhus, Fridhandler and Hayes (1997) and Cramer (1991). The Journal of Personality published a special issue on defence mechanisms (1998).

In the first definitive book on defence mechanisms, The Ego and the Mechanisms of Defence (1936), Anna Freud enumerated the ten defence mechanisms that appear in the works of her father, Sigmund Freud: repression, regression, reaction formation, isolation, undoing, projection, introjection, turning against one's own person, reversal into the opposite, and sublimation or displacement.

Sigmund Freud posited that defence mechanisms work by distorting id impulses into acceptable forms, or by unconscious or conscious blockage of these impulses. Anna Freud considered defense mechanisms as intellectual and motor automatisms of various degrees of complexity, that arose in the process of involuntary and voluntary learning.

Anna Freud introduced the concept of signal anxiety; she stated that it was "not directly a conflicted instinctual tension but a signal occurring in the ego of an anticipated instinctual tension". The signalling function of anxiety was thus seen as crucial, and biologically adapted to warn the organism of danger or a threat to its equilibrium. The anxiety is felt as an increase in bodily or mental tension, and the signal that the organism receives in this way allows for the possibility of taking defensive action regarding the perceived danger.

Both Freuds studied defence mechanisms, but Anna spent more of her time and research on five main mechanisms: repression, regression, projection, reaction formation, and sublimation. All defence mechanisms are responses to anxiety and how the consciousness and unconscious manage the stress of a social situation.

• Repression: when a feeling is hidden and forced from the consciousness to the unconscious because it is seen as socially unacceptable
• Regression: falling back into an early state of mental/physical development seen as "less demanding and safer"
• Projection: possessing a feeling that is deemed as socially unacceptable and instead of facing it, that feeling or "unconscious urge" is seen in the actions of other people
• Reaction formation: acting the opposite way that the unconscious instructs a person to behave, "often exaggerated and obsessive". For example, if a wife is infatuated with a man who is not her husband, reaction formation may cause her to – rather than cheat – become obsessed with showing her husband signs of love and affection.
• Sublimation: seen as the most acceptable of the mechanisms, an expression of anxiety in socially acceptable ways

Otto F. Kernberg (1967) developed a theory of borderline personality organization of which one consequence may be borderline personality disorder. His theory is based on ego psychological object relations theory. Borderline personality organization develops when the child cannot integrate helpful and harmful mental objects together. Kernberg views the use of primitive defence mechanisms as central to this personality organization. Primitive psychological defences are projection, denial, dissociation or splitting and they are called borderline defence mechanisms. Also, devaluation and projective identification are seen as borderline defences.

In George Eman Vaillant's (1977) categorization, defences form a continuum related to their psychoanalytical developmental level. They are classified into pathological, immature, neurotic and "mature" defences.

Robert Plutchik's (1979) theory views defences as derivatives of basic emotions, which in turn relate to particular diagnostic structures. According to his theory, reaction formation relates to joy (and manic features), denial relates to acceptance (and histrionic features), repression to fear (and passivity), regression to surprise (and borderline traits), compensation to sadness (and depression), projection to disgust (and paranoia), displacement to anger (and hostility) and intellectualization to anticipation (and obsessionality).

The Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) published by the American Psychiatric Association (1994) includes a tentative diagnostic axis for defence mechanisms. This classification is largely based on Vaillant's hierarchical view of defences, but has some modifications. Examples include: denial, fantasy, rationalization, regression, isolation, projection, and displacement.

Vaillant's categorization

Psychiatrist George Eman Vaillant introduced a four-level classification of defence mechanisms: Much of this is derived from his observations while overseeing the Grant study that began in 1937 and is on-going. In monitoring a group of men from their freshman year at Harvard until their deaths, the purpose of the study was to see longitudinally what psychological mechanisms proved to have impact over the course of a lifetime. The hierarchy was seen to correlate well with the capacity to adapt to life. His most comprehensive summary of the on-going study was published in 1977.^[25]The focus of the study is to define mental health rather than disorder.

• Level I – pathological defences (psychotic denial, delusional projection)
• Level II – immature defences (fantasy, projection, passive aggression, acting out)
• Level III – neurotic defences (intellectualization, reaction formation, dissociation, displacement, repression)
• Level IV – mature defences (humour, sublimation, suppression, altruism, anticipation)

Level 1: pathological

When predominant, the mechanisms on this level are almost always severely pathological. These defences, in conjunction, permit one effectively to rearrange external experiences to eliminate the need to cope with reality. Pathological users of these mechanisms frequently appear irrational or insane to others. These are the "pathological" defences, common in overt psychosis. However, they are normally found in dreams and throughout childhood as well. They include:

• Delusional projection: Delusions about external reality, usually of a persecutory nature
• Denial: Refusal to accept external reality because it is too threatening; arguing against an anxiety-provoking stimulus by stating it does not exist; resolution of emotional conflict and reduction of anxiety by refusing to perceive or consciously acknowledge the more unpleasant aspects of external reality
• Distortion: A gross reshaping of external reality to meet internal needs

Level 2: immature

These mechanisms are often present in adults. These mechanisms lessen distress and anxiety produced by threatening people or by an uncomfortable reality. Excessive use of such defences is seen as socially undesirable, in that they are immature, difficult to deal with and seriously out of touch with reality. These are the so-called "immature" defences and overuse almost always leads to serious problems in a person's ability to cope effectively. These defences are often seen in major depression and personality disorders. They include:

• Acting out: Direct expression of an unconscious wish or impulse in action, without conscious awareness of the emotion that drives the expressive behavior
• Hypochondriasis: An excessive preoccupation or worry about having a serious illness
• Passive-aggressive behavior: Indirect expression of hostility
• Projection: A primitive form of paranoia. Projection reduces anxiety by allowing the expression of the undesirable impulses or desires without becoming consciously aware of them; attributing one's own unacknowledged, unacceptable, or unwanted thoughts and emotions to another; includes severe prejudice and jealousy, hypervigilance to external danger, and "injustice collecting", all with the aim of shifting one's unacceptable thoughts, feelings and impulses onto someone else, such that those same thoughts, feelings, beliefs and motivations are perceived as being possessed by the other.
• Schizoid fantasy: Tendency to retreat into fantasy in order to resolve inner and outer conflicts
• Splitting: A primitive defence. Both harmful and helpful impulses are split off and segregated, frequently projected onto someone else. The defended individual segregates experiences into all-good and all-bad categories, with no room for ambiguity and ambivalence. When "splitting" is combined with "projecting", the undesirable qualities that one unconsciously perceives oneself as possessing, one consciously attributes to another.

Level 3: neurotic

These mechanisms are considered neurotic, but fairly common in adults. Such defences have short-term advantages in coping, but can often cause long-term problems in relationships, work and in enjoying life when used as one's primary style of coping with the world. They include:

• Displacement: Defence mechanism that shifts sexual or aggressive impulses to a more acceptable or less threatening target; redirecting emotion to a safer outlet; separation of emotion from its real object and redirection of the intense emotion toward someone or something that is less offensive or threatening in order to avoid dealing directly with what is frightening or threatening.
• Dissociation: Temporary drastic modification of one's personal identity or character to avoid emotional distress; separation or postponement of a feeling that normally would accompany a situation or thought.
• Intellectualization: Excessively analytical or abstract thought patterns, potentially leading to increased distance from one's emotions. Used to block out conflicting or disturbing feelings or thoughts.
• Isolation of affect: The detachment of emotion from an idea, making it "flat." Frequently observed in obsessive–compulsive disorder, and in non-disordered people following traumatic events.
• Reaction formation: Converting unconscious wishes or impulses that are perceived to be dangerous or unacceptable into their opposites; behaviour that is completely the opposite of what one really wants or feels; taking the opposite belief because the true belief causes anxiety
• Repression: The process of attempting to repel desires towards pleasurable instincts, caused by a threat of suffering if the desire is satisfied; the desire is moved to the unconscious in the attempt to prevent it from entering consciousness; seemingly unexplainable naivety, memory lapse or lack of awareness of one's own situation and condition; the emotion is conscious, but the idea behind it is absent

Level 4: mature

These are commonly found among emotionally healthy adults and are considered mature, even though many have their origins in an immature stage of development. They are conscious processes, adapted through the years in order to optimise success in human society and relationships. The use of these defences enhances pleasure and feelings of control. These defences help to integrate conflicting emotions and thoughts, whilst still remaining effective. Those who use these mechanisms are usually considered virtuous. Mature defences include:

• Altruism: Constructive service to others that brings pleasure and personal satisfaction
• Anticipation: Realistic planning for future discomfort
• Humour: Overt expression of ideas and feelings (especially those that are unpleasant to focus on or too terrible to talk about directly) that gives pleasure to others. The thoughts retain a portion of their innate distress, but they are "skirted around" by witticism, for example, self-deprecation.
• Sublimation: Transformation of unhelpful emotions or instincts into healthy actions, behaviours, or emotions; for example, playing a heavy contact sport such as football or rugby can transform aggression into a game
• Suppression: The conscious decision to delay paying attention to a thought, emotion, or need in order to cope with the present reality; making it possible later to access uncomfortable or distressing emotions whilst accepting them

Other defence mechanisms

Diagram of selected ego defence mechanisms

Pathological

• Conversion: The expression of an intrapsychic conflict as a physical symptom; examples include blindness, deafness, paralysis, or numbness. This phenomenon is sometimes called hysteria.

Immature

• Idealization: Tending to perceive another individual as having more desirable qualities than they may actually have.
• Introjection: Identifying with some idea or object so deeply that it becomes a part of that person. For example, introjection occurs when we take on attributes of other people who seem better able to cope with the situation than we do.
• Projective identification: The object of projection invokes in that person a version of the thoughts, feelings or behaviours projected.
• Somatization: The transformation of uncomfortable feelings towards others into uncomfortable feelings toward oneself: pain, illness, and anxiety.
• Wishful thinking: Making decisions according to what might be pleasing to imagine instead of by appealing to evidence, rationality, or reality.

Neurotic

• Isolation: Separation of feelings from ideas and events, for example, describing a murder with graphic details with no emotional response.
• Rationalization (making excuses): Convincing oneself that no wrong has been done and that all is or was all right through faulty and false reasoning. An indicator of this defence mechanism can be seen socially as the formulation of convenient excuses.
• Regression: Temporary reversion of the ego to an earlier stage of development rather than handling unacceptable impulses in a more adult way, for example, using whining as a method of communicating despite already having acquired the ability to speak with an appropriate level of maturity.
• Undoing: A person tries to 'undo' an unhealthy, destructive or otherwise threatening thought by acting out the reverse of the unacceptable. Involves symbolically nullifying an unacceptable or guilt provoking thought, idea, or feeling by confession or atonement.
• Upward and downward social comparisons: A defensive tendency that is used as a means of self-evaluation. Individuals will look to another individual or comparison group who are considered to be worse off in order to dissociate themselves from perceived similarities and to make themselves feel better about themselves or their personal situation.
• Withdrawal: Avoidance is a form of defence. It entails removing oneself from events, stimuli, and interactions under the threat of being reminded of painful thoughts and feelings.

Relation with coping

See also: Coping (psychology)

There are many different perspectives on how the construct of defence relates to the construct of coping; some writers differentiate the constructs in various ways, but "an important literature exists that does not make any difference between the two concepts". In at least one of his books, George Eman Vaillant stated that he "will use the terms adaptation, resilience, coping, and defense interchangeably".