Abnormal Psychology

Understanding Psychological Disorders: The Neuropsychosocial Approach 49

this, they made a very loud sound immediately after a white rat

(which was used as the neutral stimulus) moved into the child’s

view; they repeated this procedure several times. Whenever Lit-

tle Albert subsequently saw a white rat, he would cry or exhibit

other signs of fear. The process that generated Little Albert’s fear

of white rats is called classical conditioning—a type of learning

that occurs when two stimuli are paired so that a neutral stimu-

lus becomes associated with another stimulus that elicits a

refl exive behavior; classical conditioning is also referred to (less

commonly) as Pavlovian conditioning. By experiencing pairings

of the two stimuli (the white rat and the loud noise in the case of

Little Albert), the person comes to respond to the neutral stim-

ulus alone (the white rat) in the same way that he or she had

responded to the stimulus that elicited the refl exive behavior

(the loud noise).

How, specifically, does classical conditioning occur? Using

the lingo of psychologists, the stimulus that reflexively elicits a

behavior is called the unconditioned stimulus (UCS), because it

elicits the behavior without prior conditioning. In the case of Little

Albert, the loud noise was the UCS, and the behavior it refl exively

elicited was a startle response associated with fear. Such a refl exive

behavior is called an unconditioned response (UCR). The neutral

stimulus that, when paired with the UCS, comes to elicit the re-

fl exive behavior is called the conditioned stimulus (CS). It is called

the conditioned stimulus because its ability to elicit the response

isconditional on its being paired with a UCS. In Little Albert’s

case, the CS was the white rat. The conditioned response (CR) is

the response that comes to be elicited by the previously neutral

stimulus (the CR is basically the same behavior as the UCR, but the

behavior is elicited by the CS). In Little Albert’s case, the CR was

the startle response to the rat alone (and ensuing fear-related behaviors, such

as crying and trying to avoid the rat). The process of classical conditioning is

illustrated in Figure 2.7.

Although various refl exive behaviors, such as salivation, can be classically con-

ditioned (Pavlov, 1927), the ones most important for understanding psychopathol-

ogy are those related to emotional responses such as fear and arousal (Davey, 1987;

Schafe & LeDoux, 2004). When emotions and emotion-related behaviors are clas-

sically conditioned, they are referred to as conditioned emotional responses. People

who have the personality characteristic of being generally emotionally reactive—

referred to as being high in neuroticism—are more likely to develop conditioned

emotional responses than are people who do not have this personality characteristic

(Bienvenu et al., 2001).

Conditioned responses can also generalize, so that they are elicited by stimuli

that are similar to the conditioned stimulus, a process called stimulus generalization.

For instance, Little Albert became afraid not only of white rats, but also of other

white furry things. He even became afraid of a piece of white cotton! His fear of

rats had generalized to similar stimuli.

As we shall see in detail in later chapters, classical conditioning is of interest to

those studying psychological disorders because it helps to explain:

• various types of anxiety disorders, particularly phobias, like Little Albert’s

phobia;

• mechanisms related to substance abuse and dependence (Hyman, 2005);


• the development of specifi c types of sexual disorders (Domjan, Cusato, & Krause,

2004).

Unconditioned stimulus (UCS)

A stimulus that refl exively elicits a behavior.

Unconditioned response (UCR)

A behavior that is refl exively elicited by a

stimulus.

Conditioned stimulus (CS)

A neutral stimulus that, when paired with an

unconditioned stimulus, comes to elicit the

refl exive behavior.

Conditioned response (CR)

A response that comes to be elicited by the

previously neutral stimulus that has become

a conditioned stimulus.

Conditioned emotional responses

Emotions and emotion-related behaviors that

are classically conditioned.

Stimulus generalization

The process whereby responses come to

be elicited by stimuli that are similar to the

conditioned stimulus.

2.7 • Classical Conditioning of a Fear: Little Albert

Figure 2.7

27 • ClassicalConditioningofaFear:LittleAlbert

Before Classical Conditioning

UCS

loud noise fear

UCR

Neutral

stimulus

white rat

no

response

During Classical Conditioning

UCS

loud noise

UCR

fear

After Classical Conditioning

CR

fear

(of rats)

CS

white rat

Neutral

stimulus

white rat