What are the essential features of anxiety disorders

What are the essential features of anxiety disorders

6 panic, anxiety, obsessions, and their disorders

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learning objectives 6

·  6.1 What are the essential features of anxiety disorders?

·  6.2 Describe the clinical features of specific and social phobias.

·  6.3 Why do anxiety disorders develop?

·  6.4 What are the clinical features of panic disorder?

·  6.5 What factors are implicated in the development of panic disorder?

·  6.6 Describe the clinical aspects of generalized anxiety disorder.

·  6.7 How are anxiety disorders treated?

·  6.8 What are the clinical features of obsessive-compulsive disorder and how is this disorder treated?

·  6.9 Describe three obsessive-compulsive related disorders.

Leni: Worried About Worrying So Much Leni is a 24-year-old graduate student. Although she is doing exceptionally well in her program, for the past year she has worried constantly that she will fail and be thrown out. When her fellow students and professors try to reassure her, Leni worries that they are just pretending to be nice to her because she is such a weak student. Leni also worries about her mother becoming ill and about whether she is really liked by her friends. Although Leni is able to acknowledge that her fears are excessive (she has supportive friends, her mother is in good health, and, based on her grades, Leni is one of the top students in her program), she still struggles to control her worrying. Leni has difficulty sleeping, often feels nervous and on edge, and experiences a great deal of muscle tension. When her friends suggested she take a yoga class to try and relax, Leni even began to worry about that, fearing that she would be the worse student in the class. “I know it makes no sense,” she says, “But that’s how I am. I’ve always been a worrier. I even worry about worrying so much!”

Anxiety  involves a general feeling of apprehension about possible future danger, and  fear  is an alarm reaction that occurs in response to immediate danger. Today the DSM has identified a group of disorders—known as the anxiety disorders—that share obvious symptoms of clinically significant fear or anxiety. Anxiety disorders affect approximately 25 to 29 percent of the U.S. population at some point in their lives and are the most common category of disorders for women and the second most common for men (Kessler et al.,  1994 ; Kessler, Berglund, Delmar, et al.,  2005 ). In any 12-month period, about 18 percent of the adult population suffers from at least one anxiety disorder (Kessler, Chiu, et al.,  2005c ). Anxiety disorders create enormous personal, economic, and health care problems for those affected. Some years ago several studies estimated that the anxiety disorders cost the United States somewhere between $42.3 billion and $47 billion in direct and indirect costs (about 30 percent of the nation’s total mental health bill of $148 billion in 1990; Greenberg et al.,  1999 ; Kessler & Greenberg,  2002 ). The figure is no doubt even higher now. Anxiety disorders are also associated with an increased prevalence of a number of medical conditions including asthma, chronic pain, hypertension, arthritis, cardiovascular disease, and irritable bowel syndrome (Roy-Byrne et al.,  2008 ) and people with anxiety disorders are very high users of medical services (e.g., Chavira et al.,  2009 ).

In this chapter, we describe a number of different anxiety disorders. We also focus on  obsessive-compulsive disorder (OCD)  Obsessions  are persistent and highly recurrent intrusive thoughts or images that are experienced as disturbing and inappropriate. People affected by such obsessions try to resist or suppress them, or to neutralize them with some other thought or action. Compulsions are repetitive behaviors (such as hand-washing or checking) that the person feels must be performed in response to the obsession. Compulsions are sometimes performed as lengthy rituals. These behaviors have the goal of preventing or reducing distress or preventing some dreaded outcome from occurring.

Historically, anxiety and obsessive-compulsive disorders were considered to be classic neurotic disorders. Although individuals with  neurotic disorders  show maladaptive and self-defeating behaviors, they are not incoherent, dangerous, or out of touch with reality. To Freud, these neurotic disorders developed when intrapsychic conflict produced significant anxiety. Anxiety was, in Freud’s formulation, a sign of an inner battle or conflict between some primitive desire (from the id) and prohibitions against its expression (from the ego and superego). Sometimes this anxiety was overtly expressed (as in those disorders known today as the anxiety disorders). In certain other neurotic disorders, however, he believed that the anxiety might not be obvious, either to the person involved or to others, if psychological defense mechanisms were able to deflect or mask it. The term neurosis was dropped from the DSM in 1980. In addition, in DSM-III, some disorders that did not involve obvious anxiety symptoms were reclassified as either dissociative or somatoform disorders (some neurotic disorders were absorbed into the mood disorders category as well—see  Chapters 7  and  8 ). This change was made to group together smaller sets of disorders that shared more obvious symptoms and features. In DSM-5 this trend has gone a step further. Obsessive-compulsive disorder is no longer classified as an anxiety disorder. Instead, it is now listed in a new DSM-5category called  obsessive-compulsive and related disorders  (see Thinking Critically about DSM-5).

We begin by discussing the nature of fear and anxiety as emotional and cognitive states and patterns of responding, each of which has an extremely important adaptive value but to which humans at times seem all too vulnerable. We will then move to a discussion of the anxiety disorders. Finally, we consider OCD and other disorders from the new obsessive-compulsive and related disorders category.

The Fear and Anxiety Response Patterns

There has never been complete agreement about how distinct the two emotions of fear and anxiety are from each other. Historically, the most common way of distinguishing between the fear and anxiety response patterns has been whether there is a clear and obvious source of danger that would be regarded as real by most people. When the source of danger is obvious, the experienced emotion has been called fear (e.g., “I’m afraid of snakes”). With anxiety, however, we frequently cannot specify clearly what the danger is (e.g., “I’m anxious about my parents’ health”).

Fear

In recent years, however, many prominent researchers have proposed a more fundamental distinction between the fear and anxiety response patterns (e.g., Barlow,  1988  2002 ; Bouton,  2005 ; Grillon,  2008 ; McNaughton,  2008 ). According to these theorists, fear is a basic emotion (shared by many animals) that involves activation of the “fight-or-flight” response of the autonomic nervous system. This is an almost instantaneous reaction to any imminent threat such as a dangerous predator or someone pointing a loaded gun.

Its adaptive value as a primitive alarm response to imminent danger is that it allows us to escape. When the fear response occurs in the absence of any obvious external danger, we say the person has had a spontaneous or uncued  panic attack . The symptoms of a panic attack are nearly identical to those experienced during a state of fear except that panic attacks are often accompanied by a subjective sense of impending doom, including fears of dying, going crazy, or losing control. These latter cognitive symptoms do not generally occur during fear states. Thus fear and panic have three components:

·  1. cognitive/subjective components (“I feel afraid/terriffied”; “I’m going to die”)

·  2. physiological components (such as increased heart rate and heavy breathing)

·  3. behavioral components (a strong urge to escape or Thee; Lang,  1968  1971 )

DSM-5 THINKING CRITICALLY about DSM-5: Why Is OCD No Longer Considered to Be an Anxiety Disorder?

In DSM-5, obsessive-compulsive disorder was removed from the anxiety disorders category and placed into a new category called “obsessive-compulsive and related disorders.” (As you already know from  Chapter 5 , PTSD was also removed and put into a new category called “trauma and stressor-related disorders.”)

One reason for moving OCD into the new category was that anxiety is not generally used as an indicator of OCD severity. Indeed, for people with certain forms of OCD such as symmetry-related obsessions and compulsions, anxiety is not even a prominent symptom. It was also noted that anxiety occurs in a wide range of disorders, so the presence of some anxiety is not a valid reason to regard OCD an anxiety disorder. Indeed Stein et al. ( 2010 ) wrote that “the highly stereotyped, driven, repetitive, and nonfunctional quality of compulsive behaviors differentiate OCD from normal acts and from the types of avoidance that occur in other anxiety disorders” ( p. 497 ).

Yet another reason is that the neurobiological underpinnings of OCD appear to be rather different from those of other anxiety disorders, focusing on frontal-striatal neural circuitry including the orbitofrontal cortex, anterior cingulate cortex, and striatum (especially the caudate nucleus). Studies examining the “OCD-related disorders” such as body dysmorphic disorder (obsessing about perceived or imagined flaws in physical appearance) and trichotillomania (chronic hair pulling) also suggest shared involvement of frontal-striatal neural circuitry. Finally, other anxiety disorders respond to a wider range of medication treatments than does OCD, which seems to respond selectively to selective serotonin reuptake inhibitors.

How compelling do these reasons sound to you? What kinds of research findings might further support the grouping of OCD with related disorders such as hoarding or trichotillomania? On the contrary, what research findings might incline you to think that it was wrong to remove OCD from the anxiety disorders category?

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Fear or panic is a basic emotion that is shared by many animals, including humans, and may activate the fight-or-flight response of the sympathetic nervous system. This allows us to respond rapidly when faced with a dangerous situation, such as being threatened by a predator. In humans who are having a panic attack, there is no external threat; panic occurs because of some misfiring of this response system.

These components are only “loosely coupled” (Lang,  1985 ), which means that someone might show, for example, physiological and behavioral indications of fear or panic without much of the subjective component, or vice versa.

Anxiety

In contrast to fear and panic, the anxiety response pattern is a complex blend of unpleasant emotions and cognitions that is both more oriented to the future and much more diffuse than fear (Barlow,  1988  2002 ). But like fear, it has not only cognitive/subjective components but also physiological and behavioral components. At the cognitive/subjective level, anxiety involves negative mood, worry about possible future threats or danger, self-preoccupation, and a sense of being unable to predict the future threat or to control it if it occurs. At a physiological level, anxiety often creates a state of tension and chronic overarousal, which may reflect risk assessment and readiness for dealing with danger should it occur (“Something awful may happen, and I had better be ready for it if it does”). Although there is no activation of the fight-or-flight response as there is with fear, anxiety does prepare or prime a person for the fight-or-flight response should the anticipated danger occur. At a behavioral level, anxiety may create a strong tendency to avoid situations where danger might be encountered, but there is not the immediate behavioral urge to flee with anxiety as there is with fear (Barlow,  1988  2002 ). Support for the idea that anxiety is descriptively and functionally distinct from fear or panic comes both from complex statistical analyses of subjective reports of panic and anxiety and from a great deal of neurobiological evidence (e.g., Bouton,  2005 ; Bouton et al.,  2001 ; Davis,  2006 ; Grillon,  2008 ).

The adaptive value of anxiety may be that it helps us plan and prepare for possible threat. In mild to moderate degrees, anxiety actually enhances learning and performance. For example, a mild amount of anxiety about how you are going to do on your next exam, or in your next tennis match, can actually be helpful. But although anxiety is often adaptive in mild or moderate degrees, it is maladaptive when it becomes chronic and severe, as we see in people diagnosed with anxiety disorders.

Although there are many threatening situations that provoke fear or anxiety unconditionally, many of our sources of fear and anxiety are learned. Years of human and nonhuman animal experimentation have established that the basic fear and anxiety response patterns are highly conditionable (e.g., Fanselow & Ponnusamy,  2008 ; Lipp,  2006 ). That is, previously neutral and novel stimuli (conditioned stimuli) that are repeatedly paired with, and reliably predict, frightening or unpleasant events such as various kinds of physical or psychological trauma (unconditioned stimulus) can acquire the capacity to elicit fear or anxiety themselves (conditioned response). Such conditioning is a completely normal and adaptive process that allows all of us to learn to anticipate upcoming frightening events if they are reliably preceded by a signal. Yet this normal and adaptive process can also lead in some cases to the development of clinically significant fears and anxieties, as we will see.

For example, a girl named Angela sometimes saw and heard her father physically abuse her mother in the evening. After this happened four or five times, Angela started to become anxious as soon as she heard her father’s car arrive in the driveway at the end of the day. In such situations a wide variety of initially neutral stimuli may accidentally come to serve as cues that something threatening and unpleasant is about to happen—and thereby come to elicit fear or anxiety themselves. Our thoughts and images can also serve as conditioned stimuli capable of eliciting the fear or anxiety response pattern. For example, Angela came to feel anxious even when thinking about her father.

in review

·  ● Compare and contrast fear or panic with anxiety, making sure to note that both emotions involve three response systems.

·  ● Explain the significance of the fact that both fear and anxiety can be classically conditioned.

Overview of the Anxiety Disorders and their Commonalities

Anxiety disorders  all have unrealistic, irrational fears or anxieties of disabling intensity as their principal and most obvious manifestation. Among the disorders recognized in DSM-5 are:

·  1. specific phobia

·  2. social anxiety disorder (social phobia)

·  3. panic disorder

·  4. agoraphobia

·  5. generalized anxiety disorder

As seen in the following brief overview, people with these varied disorders differ from one another both in terms of the relative preponderance of fear or panic versus anxiety symptoms that they experience and in the kinds of objects or situations that most concern them. For example, people with specific or social phobias exhibit many anxiety symptoms about the possibility of encountering their phobic situation, but they may also experience a fear or panic response when they actually encounter the situation. People with panic disorder experience both frequent panic attacks and intense anxiety focused on the possibility of having another one. People with agoraphobia go to great lengths to avoid a variety of feared situations, ranging from open streets, bridges, and crowded public places. By contrast, people with generalized anxiety disorder (like Leni in the case study that opened this chapter) mostly experience a general sense of diffuse anxiety and worry about many potentially bad things that may happen; some may also experience an occasional panic attack, but it is not a focus of their anxiety. It is also important to note that many people with one anxiety disorder will experience at least one more anxiety disorder and/or depression either concurrently or at a different point in their lives (e.g., Brown & Barlow,  2002  2009 ; Kessler, Berglund, Demler, et al.,  2005 ).

Given these commonalities across the anxiety disorders, it should come as no surprise that there are some important similarities in the basic causes of these disorders (as well as many differences). Among biological causal factors, we will see that there are genetic contributions to each of these disorders and that at least part of the genetic vulnerability may be nonspecific, or common across the disorders (e.g., Barlow,  2002 ; Craske & Waters,  2005 ). In adults, the common genetic vulnerability is manifested at a psychological level at least in part by the important personality trait called neuroticism—a proneness or disposition to experience negative mood states that is a common risk factor for both anxiety and mood disorders (e.g., Klein et al.,  2009 ). The brain structures most centrally involved in most disorders are generally in the limbic system (often known as the “emotional brain”) and certain parts of the cortex, and the neurotransmitter substances that are most centrally involved are gamma aminobutyric acid (GABA), norepinephrine, and serotonin (see  Chapter 3 ).

Among common psychological causal factors, we will see that classical conditioning of fear, panic, or anxiety to a range of stimuli plays an important role in many of these disorders (Forsyth et al.,  2006 ; Mineka & Oehlberg,  2008 ; Mineka & Zinbarg,  1996  2006 ). In addition, people who have perceptions of a lack of control over either their environments or their own emotions (or both) seem more vulnerable to developing anxiety disorders. The development of such perceptions of uncontrollability depends heavily on the social environment people are raised in, including parenting styles (Chorpita & Barlow,  1998 ; Craske & Waters,  2005 ; Mineka & Zinbarg,  2006 ; Hudson & Rapee,  2009 ). For certain disorders, faulty or distorted patterns of cognition also may play an important role. Finally, the sociocultural environment in which people are raised also has prominent effects on the kinds of objects and experiences people become anxious about or come to fear. Ultimately what we must strive for is a good biopsychosocial understanding of how all these types of causal factors interact with one another in the development of anxiety disorders.

Finally, as we will see, there are many commonalities across the effective treatments for the various anxiety disorders (e.g., Barlow,  2004 ; Campbell-Sills & Barlow,  2007 ). For each disorder, graduated exposure to feared cues, objects, and situations—until fear or anxiety begins to habituate—constitutes the single most powerful therapeutic ingredient. Further, for certain disorders the addition of cognitive restructuring techniques can provide added benefit. What these cognitive restructuring techniques for different disorders have in common is that they help the individual understand his or her distorted patterns of thinking about anxiety-related situations and how these patterns can be changed. Medications can also be useful in treating all disorders except specific phobias, and nearly all tend to fall into two primary medication categories: antianxiety medications (anxiolytics) and antidepressant medications.

We now turn to a more detailed discussion of each disorder, highlighting their common and their distinct features as well as what is known about their causes. We start with phobic disorders—the most common anxiety disorders. A  phobia  is a persistent and disproportionate fear of some specific object or situation that presents little or no actual danger and yet leads to a great deal of avoidance of these feared situations. As we will see in our discussion of DSM-5, there are three main categories of pho-bias: (1) specific phobia, (2) social phobia, and (3) agoraphobia.

in review

·  ● What is the central feature of all anxiety disorders? That is, what do they have in common?

·  ● What differentiates the anxiety disorders from one another?

·  ● What are some common kinds of biological and psychosocial causes of the different anxiety disorders?

·  ● What is the most important ingredient across effective psychosocial treatments for the anxiety disorders?

Specific Phobias

A person is diagnosed as having a  specific phobia  if she or he shows strong and persistent fear that is triggered by the presence of a specific object or situation (see DSM-5 box for diagnostic criteria). When individuals with specific phobias encounter a phobic stimulus, they often show an immediate fear response that often resembles a panic attack except for the existence of a clear external trigger (APA,  2013 ). Not surprisingly, such individuals also experience anxiety if they anticipate they may encounter a phobic object or situation and so go to great lengths to avoid encounters with their phobic stimulus. Indeed, they often even avoid seemingly innocent representations of it such as photographs or television images. For example, claustrophobic persons may go to great lengths to avoid entering a closet or an elevator, even if this means climbing many flights of stairs or turning down jobs that might require them to take an elevator. Generally, people with specific phobias recognize that their fear is somewhat excessive or unreasonable although occasionally they may not have this insight.

DSM-5 criteria for: Specific Phobia

·  A. Marked fear or anxiety about a specific object or situation (e.g., flying, heights, animals, receiving an injection, seeing blood).

Note: In children, the fear or anxiety may be expressed by crying, tantrums, freezing, or clinging.

·  B. The phobic object or situation almost always provokes immediate fear or anxiety.

·  C. The phobic object or situation is actively avoided or endured with intense fear or anxiety.

·  D. The fear or anxiety is out of proportion to the actual danger posed by the specific object or situation and to the sociocultural context.

·  E. The fear, anxiety, or avoidance is persistent, typically lasting for 6 months or more.

·  F. The fear, anxiety, or avoidance causes clinically significant distress or impairment in social, occupational, or other important areas of functioning.

·  G. The disturbance is not better explained by the symptoms of another mental disorder, including fear, anxiety, and avoidance of situations associated with panic-like symptoms or other incapacitating symptoms (as in agoraphobia); objects or situations related to obsessions (as in obsessive-compulsive disorder); reminders of traumatic events (as in posttraumatic stress disorder); separation from home or attachment figures (as in separation anxiety disorder); or social situations (as in social anxiety disorder).

Source: Reprinted with permission from the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, (Copyright 2013). American Psychiatric Association.

This avoidance is a cardinal characteristic of phobias; it occurs both because the phobic response itself is so unpleasant and because of the phobic person’s irrational appraisal of the likelihood that something terrible will happen.  Table 6.1  on page 168 lists the five subtypes of specific phobias recognized in DSM-5, along with some examples.

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People with claustrophobia may find elevators so frightening that they go to great lengths to avoid them. If for some reason they have to take an elevator, they will be very frightened and have thoughts about the elevator falling, the doors never opening, or there not being enough air to breathe.

The following case is typical of specific phobia:

A Pilot’s Wife’s Fear Mary, a married mother of three, was 47 at the time she first sought treatment for both claustrophobia and acrophobia. She reported having been intensely afraid of enclosed spaces (claustrophobia) and of heights (acrophobia) since her teens. She remembered having been locked in closets by her older siblings when she was a child; the siblings also confined her under blankets to scare her and added to her fright by showing her pictures of spiders after releasing her from under the blankets. She traced the onset of her claustrophobia to those traumatic incidents, but she had no idea why she was afraid of heights. While her children had been growing up, she had been a housewife and had managed to live a fairly normal life in spite of her two specific phobias. However, her children were now grown, and she wanted to find a job outside her home. This was proving to be very difficult because she could not take elevators and was frightened being on anything other than the first floor of an office building. Moreover, her husband had for some years been working for an airline, which entitled him to free airline tickets. The fact that Mary could not fly (due to her phobias) had become a sore point in her marriage because they both wanted to be able to take advantage of these free tickets to see distant places. Thus, although she had had these phobias for many years, they had become truly disabling only in recent years as her life circumstances had changed and she could no longer easily avoid heights or enclosed spaces.

TABLE 6.1 Subtypes of Specific Phobias in DSM-5

Phobia Type Examples
Animal Snakes, spiders, dogs, insects, birds
Natural Environment Storms, heights, water
Blood-Injection-Injury Seeing blood or an injury, receiving an injection, seeing a person in a wheelchair
Situational Public transportation, tunnels, bridges, elevators, flying, driving, enclosed spaces
Other Choking, vomiting, “space phobia” (fear of falling down if away from walls or other support)

Source: Adapted with permission from the Diagnostic and Statistical Manual of Mental Disorders, Text Revision, fifth edition (Copyright © 2013). American Psychiatric Association.

If people who suffer from phobias attempt to approach their phobic situation, they are overcome with fear or anxiety, which may vary from mild feelings of apprehension and distress (usually while still at some distance) to full-fledged activation of the fight-or-flight response. Regardless of how it begins, phobic behavior tends to be reinforced because every time the person with a phobia avoids a feared situation his or her anxiety decreases. In addition, the secondary benefits derived from being disabled, such as increased attention, sympathy, and some control over the behavior of others, may also sometimes reinforce a phobia.

One category of specific phobias that has a number of interesting and unique characteristics is  blood-injection-injury phobia . It probably occurs in about 3 to 4 percent of the population (Ayala et al.,  2009 ; Öst & Hellström,  1997 ). People afflicted with this phobia typically experience at least as much (if not more) disgust as fear (Schienle et al.,  2005 ; Teachman & Saporito,  2009 ). They also show a unique physiological response when confronted with the sight of blood or injury. Rather than showing the simple increase in heart rate and blood pressure seen when most people with phobias encounter their phobic object, these people show an initial acceleration, followed by a dramatic drop in both heart rate and blood pressure. This is very frequently accompanied by nausea, dizziness, or fainting, which do not occur with other specific phobias (Öst & Hellström,  1997 ; Page & Tan,  2009 ).

Interestingly, people with this phobia show this unique physiological response pattern only in the presence of blood and injury stimuli; they exhibit the more typical physiological response pattern characteristic of the fight-or-flight response to their other feared objects (see Dahlloef & Öst,  1998 ; Öst & Hugdahl,  1985 ). From an evolutionary and functional standpoint, this unique physiological response pattern may have evolved for a specific purpose: By fainting, the person being attacked might inhibit further attack, and if an attack did occur, the drop in blood pressure would minimize blood loss (Craske,  1999 ; Marks & Nesse,  1991 ). This type of phobia appears to be highly heritable (Czajkowski et al., 2011).

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In blood-injection-injury phobia, the afflicted person experiences disgust and fear at the sight of someone receiving an injection. When confronted with the sight of blood or injury, people with this phobic disorder often experience nausea, dizziness, and fainting.

Prevalence, Age of Onset, and Gender Differences

Specific phobias are quite common. Results of the National Comorbidity Survey-Replication, which used DSM-IV criteria, revealed a lifetime prevalence rate of about 12 percent (Kessler, Chiu, et al.,  2005c ). Among people with one specific phobia, over 75 percent have at least one other specific fear that is excessive (Curtis, Magee, et al.,  1998 ). The relative gender ratios vary considerably according to the type of specific phobia, but phobias are always considerably more common in women than in men. For example, about 90 to 95 percent of people with animal phobias are women, but the gender ratio is less than 2:1 for blood-injection-injury phobia. The average age of onset for different types of specific phobias also varies widely. Animal phobias usually begin in childhood, as do blood-injection-injury phobias and dental phobias. However, other phobias such as claustrophobia and driving phobia tend to begin in adolescence or early adulthood (Barlow,  2002 ; Öst,  1987 ).

Psychological Causal Factors

A variety of psychological causal factors have been implicated in the origins of specific phobias, ranging from deep-seated psychodynamic conflicts to relatively straightforward traumatic conditioning of fear and a multitude of individual differences in who is at risk for such conditioning.

PSYCHOANALYTIC VIEWPOINT

According to the psychoanalytic view, phobias represent a defense against anxiety that stems from repressed impulses from the id. Because it is too dangerous to “know” the repressed id impulse, the anxiety is displaced onto some external object or situation that has some symbolic relationship to the real object of the anxiety (Freud,  1909 ). However, this prototypical psychodynamic account of how phobias are acquired was long criticized as being far too speculative, and an alternative, simpler account from learning theory was first proposed by Wolpe and Rachman ( 1960 ), which has now been further refined and expanded as discussed below.

PHOBIAS AS LEARNED BEHAVIOR

As an alternative to psychoanalytic accounts, Wolpe and Rachman ( 1960 ) developed an account based on learning theory, which sought to explain the development of phobic behavior through classical conditioning. Numerous other theorists in the 1960s and 1970s also agreed that the principles of classical conditioning appeared to account for the acquisition of irrational fears and phobias. The fear response can readily be conditioned to previously neutral stimuli when these stimuli are paired with traumatic or painful events. We would also expect that, once acquired, phobic fears would generalize to other, similar objects or situations. Recall, for example, that Mary’s claustrophobia had probably been caused by multiple incidents as a child when her siblings locked her in closets and confined her under blankets to scare her. But as an adult, Mary feared elevators and caves as well as other enclosed places. The powerful role of classical conditioning in the development of pho-bias was supported in a survey by Öst and Hugdahl ( 1981 ), who administered questionnaires to 106 adult phobic clients that concerned, among other things, the purported origins of their fears (see Mineka & Sutton,  2006 , for a review). Fifty-eight percent cited traumatic conditioning experiences as the sources of their phobias. Some of these traumatic conditioning events were simply uncued panic attacks, which are now known to effectively condition fear (e.g., Acheson et al.,  2007 ; Forsyth & Eifert,  1998 ).

Vicarious Conditioning Direct traumatic conditioning in which a person has a terrifying experience in the presence of a neutral object or situation is not the only way that people can learn irrational, phobic fears. Simply watching a phobic person behaving fearfully with his or her phobic object can be distressing to the observer and can result in fear being transmitted from one person to another through vicarious or observational classical conditioning. In addition, watching a nonfearful person undergoing a frightening experience can also lead to vicarious conditioning. For example, one man, as a boy, had witnessed his grandfather vomit while dying. Shortly after this traumatic event (his grandfather’s distress while dying) the boy had developed a strong and persistent vomiting phobia. Indeed, when this man was in middle age he even contemplated suicide one time when he was nauseated and feared vomiting (Mineka & Zinbarg,  2006 ). Related experimental findings have been observed in laboratory analogue studies of human children. For example, two studies showed that 7- to 9-year-old children who saw pictures of an unfamiliar animal (an Australian marsupial) paired 10 times with fearful facial expressions showed increased fear beliefs and behavioral avoidance of this conditioned stimulus (CS) relative to children who saw the unfamiliar animal paired with happy facial expressions. These effects persisted for at least one week (Askew & Field,  2007 ; see Askew & Field,  2008 , for a review).

Animal research using rhesus monkeys has increased our confidence that vicarious conditioning of intense fears can indeed occur. In these experiments, Mineka and Cook and their colleagues (e.g., Cook & Mineka,  1989 ; Mineka & Cook,  1993 ; Mineka, Davidson, et al.,  1984 ) showed that laboratory-reared monkeys who were not initially afraid of snakes rapidly developed a phobic-like fear of snakes simply through observing a wild-reared monkey behaving fearfully with snakes. Significant fear was acquired after only 4 to 8 minutes of exposure to the wild-reared monkey with snakes, and there were no signs that the fear had diminished 3 months later. The monkeys could also learn the fear simply through watching a videotape of the wild-reared model monkey behaving fearfully with snakes. This suggests that the mass media also play a role in the vicarious conditioning of fears and phobias in people (Cook & Mineka,  1990 ; Mineka & Sutton,  2006 ).

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Monkeys who watch a model monkey (such as the one illustrated here) behaving fearfully with a live boa constrictor will rapidly acquire an intense fear of snakes themselves. Fears can thus be learned vicariously without any direct traumatic experience.

Individual Differences in Learning Does the direct and vicarious conditioning model really explain the origins of most phobias? Given all the traumas that people undergo, why don’t more people develop phobias (Mineka & Oehlberg,  2008 ; Mineka & Zinbarg,  1996  2006 ; Rachman,  1990 )? The answer seems to be, at least in good part, that differences in life experiences among individuals strongly affect whether or not conditioned fears or phobias actually develop. For example, years of positive experiences with friendly dogs before being bitten by one will probably keep a dog bite victim from developing a full-blown dog phobia. Thus, to understand individual differences in the development and maintenance of phobias, we need to understand the role of the different life experiences of people who undergo the same trauma.

Some life experiences may serve as risk factors and make certain people more vulnerable to phobias than others, and other experiences may serve as protective factors for the development of phobias (Mineka & Sutton,  2006 ). For example, children who have had more previous nontraumatic experiences with a dentist are less likely to develop dental anxiety after a bad and painful experience than are children with fewer previous nontraumatic experiences (Kent,  1997 ; Ten Berge et al.,  2002 ). This shows the importance of the individual’s prior familiarity with an object or situation in determining whether a phobia develops following a fear-conditioning experience. Moreover, Mineka and Cook ( 1986 ) showed that monkeys who first simply watched nonfearful monkeys behaving nonfearfully with snakes were immunized against acquiring a fear of snakes when they later saw fearful monkeys behaving fearfully with snakes. By analogy, if a child has extensive exposure to a nonfearful parent behaving nonfearfully with the phobic object (e.g., spiders) or situation (e.g., heights) of the other, phobic parent, this may serve as a protective factor and immunize the child against the effects of later seeing the phobic parent behaving fearfully with the phobic object (Mineka & Oehlberg,  2008 ; Mineka & Sutton,  2006 ). Egliston and Rapee ( 2007 ) reported related results in an analogue study of human toddlers who either watched their mothers reacting positively to a snake or spider, or watched the snake or spider alone. Subsequently both groups of toddlers watched an experimenter reacting with fear and disgust toward the stimulus. Those in the group who had first watched their mother behaving positively acquired less fear than those who had first watched the stimulus alone.

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A person who has had good experiences with a potentially phobic stimulus, such as the little girl playing here with her dog, is likely to be immunized from later acquiring a fear of dogs even if she has a traumatic encounter with one.

Events that occur during a conditioning experience, as well as before it, are also important in determining the level of fear that is conditioned. For example, experiencing an inescapable and uncontrollable event, such as being attacked by a dog that one cannot escape from after being bitten, is expected to condition fear much more powerfully than experiencing the same intensity of trauma that is escapable or to some extent controllable (e.g., by running away after the attack; Mineka,  1985a ; Mineka & Zinbarg,  1996  2006 ). In addition, the experiences that a person has after a conditioning experience may effect the strength and maintenance of the conditioned fear (Rescorla,  1974 ; White & Davey,  1989 ). For example, the inflation effect suggests that a person who acquired, a mild fear of driving following a minor crash might be expected to develop a full-blown phobia if he or she later were physically assaulted, even though no automobile was present during the assault (Dadds et al.,  2001 ; Mineka,  1985b ; Mineka & Zinbarg,  1996  2006 ). Even verbal information that later alters one’s interpretation of the dangerousness of a previous trauma can inflate the level of fear (e.g., being told, “You’re lucky to be alive because the man who crashed into your car last week had lost his license due to a record of drunk driving leading to fatal car crashes”; Dadds et al.,  2001 ). Another way in which fear of a CS can be inflated following conditioning is if the organism later is exposed to uncontrollable stress (Baratta et al.,  2007 ). These examples show that the factors involved in the origins and maintenance of fears and phobias are more complex than suggested by the traditional, simplistic conditioning view, although they are nevertheless consistent with contemporary views of conditioning (Mineka & Oehlberg,  2008 ; see also Coelho & Purkis,  2009 ; Laborda & Miller,  2011 ).

It has also been shown that our cognitions, or thoughts, can help maintain our phobias once they have been acquired. For example, people with phobias are constantly on the alert for their phobic objects or situations and for other stimuli relevant to their phobia (McNally & Reese,  2009 ). Nonphobic persons, by contrast, tend to direct their attention away from threatening stimuli (see Mineka, Rafaeli, & Yovel,  2003 ). In addition, phobics also markedly overestimate the probability that feared objects have been, or will be, followed by frightening events. This cognitive bias may help maintain or strengthen phobic fears with the passage of time (Muhlberger et al.,  2006 ; Öhman & Mineka,  2001 ; Tomarken, Mineka, & Cook,  1989 ).

Evolutionary Preparedness for Learning Certain Fears and Phobias Consider the observation that people are much more likely to have phobias of snakes, water, heights, and enclosed spaces than of motorcycles and guns, even though the latter objects may be at least as likely to be associated with trauma. This is because our evolutionary history has affected which stimuli we are most likely to come to fear. Primates and humans seem to be evolutionarily prepared to rapidly associate certain objects—such as snakes, spiders, water, and enclosed spaces—with frightening or unpleasant events (e.g., Mineka & Öhman,  2002 ; Öhman,  1996 ; Seligman,  1971 ). This  prepared learning  occurs because, over the course of evolution, those primates and humans who rapidly acquired fears of certain objects or situations that posed real threats to our early ancestors may have enjoyed a selective advantage. Thus “prepared” fears are not inborn or innate but rather are easily acquired or especially resistant to extinction. Guns and motorcycles, by contrast, were not present in our early evolutionary history and so did not convey any such selective advantage.

There is now a large amount of experimental evidence supporting the preparedness theory of phobias. In one important series of experiments using human subjects, Öhman and his colleagues (see Öhman,  1996 ; Öhman,  2009 ; Öhman & Mineka,  2001 , for reviews) found that fear is conditioned more effectively to fear-relevant stimuli (slides of snakes and spiders) than to fear-irrelevant stimuli (slides of flowers and mushrooms). These researchers also found that once the individuals acquired the conditioned responses to fear-relevant stimuli, these responses (including activation of the relevant brain area, the amygdala) could be elicited even when the fear-relevant stimuli (but not the fear-irrelevant stimuli) were presented subliminally (i.e., presentation was so brief that the stimuli were not consciously perceived; e.g., Carlsson et al.,  2004 ; Öhman et al.,  2007 ). This subliminal activation of responses to phobic stimuli may help to account for certain aspects of the irrationality of phobias. That is, people with phobias may not be able to control their fear because the fear may arise from cognitive structures that are not under conscious control (Öhman & Mineka,  2001 ; Öhman & Soares,  1993 ).

Another series of experiments showed that lab-reared monkeys in a vicarious conditioning paradigm can easily acquire fears of fear-relevant stimuli such as toy snakes and toy crocodiles but not of fear-irrelevant stimuli such as flowers and a toy rabbit (Cook & Mineka,  1989  1990 ). Thus, both monkeys and humans seem selectively to associate certain fear-relevant stimuli with threat or danger. Moreover, these lab-reared monkeys had had no prior exposure to any of the stimuli involved (e.g., snakes or flowers) before participating in these experiments. Thus, the monkey results support the evolutionarily based preparedness hypothesis even more strongly than the human experiments. For example, human subjects (unlike the lab-reared monkeys) might show superior conditioning to snakes or spiders because of preexisting negative associations to snakes or spiders rather than because of evolutionary factors (Mineka & Öhman,  2002 ).

Biological Causal Factors

Genetic and temperamental variables affect the speed and strength of conditioning of fear (e.g., Gray,  1987 ; Hettema et al.,  2003 ; Oehlberg & Mineka,  2011 ). That is, depending on their genetic makeup or their temperament and personality (all of which are clearly related; see  Chapter 3 ), people are more or less likely to acquire fears and phobias. For example, Lonsdorf and colleagues ( 2009 ) found that individuals who are carriers of one of the two variants on the serotonin-transporter gene (the s allele, which has been linked to heightened neuroticism) show superior fear conditioning relative to individuals who do not carry the s allele. However, those with one of two variants of a different gene (the COMT met/met genotype) did not show superior conditioning but did show enhanced resistance to extinction (see also Lonsdorf & Kalisch, 2011). Relatedly, Kagan and his colleagues ( 2001 ) found that behaviorally inhibitedtoddlers (who are excessively timid, shy, easily distressed, etc.) at 21 months of age were at higher risk of developing multiple specific phobias by 7 to 8 years of age than were uninhibited children (32 versus 5 percent). The average number of reported fears in the inhibited group was three to four per child (Biederman et al.,  1990 ).

Several behavior genetic studies also suggest a modest genetic contribution to the development of specific phobias. For example, a large female twin study found that monozygotic (identical) twins were more likely to share animal phobias and situational phobias (such as of heights or water) than were dizygotic (nonidentical) twins (Kendler et al.,  1999b ). Very similar results were later also found for men (Hettema et al.,  2005 ). However, the same studies also found evidence that nonshared environmental factors (i.e., individual specific experiences not shared by twins) also played a very substantial role in the origins of specific phobias, a result that supports the idea that phobias are learned behaviors. Another study found that the heritability of animal phobias was separate from the heritability of complex phobias such as social phobia and agoraphobia (Czajkowski et al., 2011).

Treatments

A form of behavior therapy called  exposure therapy —which is the best treatment for specific phobias—involves controlled exposure to the stimuli or situations that elicit phobic fear (Choy et al.,  2007 ; Craske & Mystkowski,  2006 ). Clients are gradually placed—symbolically or increasingly under “real-life” conditions—in those situations they find most frightening. In treatment, clients are encouraged to expose themselves (either alone or with the aid of a therapist or friend) to their feared situations for long enough periods of time so that their fear begins to subside. One variant on this procedure, known as participant modeling, is often more effective than exposure alone. Here the therapist calmly models ways of interacting with the phobic stimulus or situation (Bandura,  1977  1997 ). These techniques enable clients to learn that these situations are not as frightening as they had thought and that their anxiety, while unpleasant, is not harmful and will gradually dissipate (Craske & Mystkowski,  2006 ; Craske & Rowe,  1997 ). The new learning is probably mediated by changes in brain activation in the amygdala, which is centrally involved in the emotion of fear.

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One variation on exposure therapy is called participant modeling. Here the therapist models how to touch and pick up a live tarantula and encourages the spider-phobic client to imitate her behavior. This treatment is graduated, with the client’s first task being simply to touch the tarantula from the outside of the cage, then to touch the tarantula with a stick, then with a gloved hand, then with a bare hand, and finally to let the tarantula crawl over his hand. This is a highly effective treatment, with the most spider-phobic clients being able to reach the top of the hierarchy within 60 to 90 minutes.

For certain phobias such as small-animal phobias, flying phobia, claustrophobia, and blood-injury phobia, exposure therapy is often highly effective when administered in a single long session (of up to 3 hours) (Öst,  1997 ; Öst et al.,  2001 ). This can be an advantage because some people are more likely to seek treatment if they have to go only once. This treatment has also been shown to be highly effective in youth with specific phobias (e.g., Ollendick et al.,  2009 ).

An example of the use of exposure therapy comes from the treatment of Mary, the housewife whose acrophobia and claustrophobia we described earlier.

Mary’s Treatment Treatment consisted of 13 sessions of graduated exposure exercises in which the therapist accompanied Mary first into mildly fear-provoking situations and then gradually into more and more fear-provoking situations. Mary also engaged in homework, doing these exposure exercises by herself. The prolonged in vivo (“real-life”) exposure sessions lasted as long as necessary for her anxiety to subside. Initial sessions focused on Mary’s claustrophobia and on getting her to be able to ride for a few floors in an elevator, first with the therapist and then alone. Later she took longer elevator rides in taller buildings. Exposure for the acrophobia consisted of walking around the periphery of the inner atrium on the top floor of a tall hotel and, later, spending time at a mountain vista overlook spot. The top of the claustrophobia hierarchy consisted of taking a tour of an underground cave. After 13 sessions, Mary successfully took a flight with her husband to Europe and climbed to the top of many tall tourist attractions there.

Recently, some therapists have begun to use virtual reality environments to simulate certain kinds of phobic situations, such as heights and airplanes, as places to conduct exposure treatment. If such techniques were highly effective and widely available, there would be no need to conduct treatment in real situations (such as real airplanes or tall buildings). About a dozen controlled studies have yielded very promising results. Moreover, although the results are not yet entirely conclusive, it appears that the relative efficacy of virtual reality versus live exposure is comparable (e.g., Choy et al.,  2007 ; Parsons & Rizzo,  2008 ; Rothbaum et al.,  2006 ).

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New treatments using virtual reality environments allow therapists to simulate certain kinds of phobic situations, such as standing at heights or sitting in airplanes, in a contrived setting.

Some researchers have also tried combining cognitive restructuring techniques or medications with exposure-based techniques to see if this can produce additional gains. In general, studies using cognitive techniques alone have not produced results as good as those using exposure-based techniques, and the addition of cognitive techniques has generally not added much (Craske & Mystkowski,  2006 ; Wolitzky-Taylor et al.,  2008 ). Similarly, medication treatments are ineffective by themselves, and there is even some evidence that antianxiety medications may interfere with the beneficial effects of exposure therapy (Antony & Barlow,  2002 ; Choy et al.,  2007 ). Recently, however, some studies have shown that a drug called d-cycloserine, which is known to facilitate extinction of conditioned fear in animals (e.g., Davis et al.,  2005 ; Davis et al.,  2006 ), may enhance the effectiveness of small amounts of exposure therapy for fear of heights in a virtual reality environment (Ressler et al.,  2004 ; Norberg et al.,  2008 ). D-cyloserine by itself, however, has no effect. These results are very promising, but much more work is necessary before it will be known how useful this drug will be in enhancing the effects of exposure therapy for many different kinds of phobias.

in review

·  ● What are the five subtypes of specific phobias?

·  ● Describe the original classical conditioning explanation for the origins of specific phobias as well as how vicarious conditioning may be involved.

·  ● Explain several sources of individual differences in learning that have improved and expanded the basic conditioning hypothesis of phobia acquisition.

·  ● Explain how evolutionary factors have influenced which objects and situations we are most likely to learn to fear.

·  ● Describe the most effective treatment for specific phobias.

Social Phobias

Social phobia  (or social anxiety disorder), as the DSM-5 describes it, is characterized by disabling fears of one or more specific social situations (such as public speaking, urinating in a public bathroom, or eating or writing in public; see the DSM-5 box). In these situations, a person fears that she or he may be exposed to the scrutiny and potential negative evaluation of others or that she or he may act in an embarrassing or humiliating manner. Because of their fears, people with social phobias either avoid these situations or endure them with great distress. Intense fear of public speaking is the single most common type of social phobia. DSM-5 also identifies two subtypes of social phobia, one of which centers on performance situations such as public speaking and one of which is more general and includes nonperformance situations (such as eating in public). Indeed, people with the more general subtype of social phobia often have significant fears of most social situations (rather than simply a few) and often also have a diagnosis of avoid-ant personality disorder (see  Chapter 10 ; e.g., Skodol et al.,  1995 ; Stein & Stein,  2008 ). image9 Watch the Video Steve: Social Phobia on MyPsychLab

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Prevalence, Age of Onset, and Gender Differences

The diagnosis of social phobia is very common and occurs even in famous performers such as Barbra Streisand and Carly Simon. The National Comorbidity Survey-Replication estimated that about 12 percent of the population will qualify for a diagnosis of social phobia at some point in their lives (Kessler, Berglund, Demler, et al.,  2005 ; Ruscio et al.,  2008 ). This disorder is somewhat more common among women than men (about 60 percent of sufferers are women). Unlike specific phobias, which most often originate in childhood, social phobias typically begin somewhat later, during early or middle adolescence or certainly by early adulthood (Bruce et al.,  2005 ; Ruscio et al.,  2008 ). Nearly two-thirds of people with social phobia suffer from one or more additional anxiety disorders at some point in their lives, and about 50 percent also suffer from a depressive disorder at the same time (Kessler, Chiu, et al., 2005; Ruscio et al.,  2008 ). Approximately one-third abuse alcohol to reduce their anxiety and help them face the situations they fear (for example, drinking before going to a party; Magee et al.,  1996 ). Moreover, because of their distress and avoidance of social situations, people with social phobia, on average, have lower employment rates and lower socioeconomic status, and approximately one-third have severe impairment in one or more domains of their life (Harvey et al.,  2005 ; Ruscio et al.,  2008 ). Finally, the disorder is remarkably persistent, with one study finding that only 37 percent recovered spontaneously over a 12-year period (Bruce et al.,  2005 ).

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Intense fear of public speaking is the single most common social phobia.

The case of Paul is typical of social phobia (except that not all people with social phobia have full-blown panic attacks, as Paul did, in their socially phobic situations).

A Surgeon’s Social Phobia Paul was a single white male in his mid-30s when he first presented for treatment. He was a surgeon who reported a 13-year history of social phobia. He had very few social outlets because of his persistent concerns that people would notice how nervous he was in social situations, and he had not dated in many years. Convinced that people would perceive him as foolish or crazy, he particularly worried that people would notice how his jaw tensed up when around other people. Paul frequently chewed gum in public situations, believing that this kept his face from looking distorted. Notably, he had no particular problems talking with people in professional situations. For example, he was quite calm talking with patients before and after surgery. During surgery, when his face was covered with a mask, he also had no trouble carrying out surgical tasks or interacting with the other surgeons and nurses in the room. The trouble began when he left the operating room and had to make small talk—and eye contact—with the other doctors and nurses or with the patient’s family. He frequently had panic attacks in these social situations. During the panic attacks he experienced heart palpitations, fears of “going crazy,” and a sense of his mind “shutting down.” Because the panic attacks occurred only in social situations, he was diagnosed as having social phobia rather than panic disorder.

Paul’s social phobia and panic had begun about 13 years earlier when he was under a great deal of stress. His family’s business had failed, his parents had divorced, and his mother had had a heart attack. It was in this context of multiple stressors that a personally traumatic incident probably triggered the onset of his social phobia. One day he had come home from medical school to find his best friend in bed with his fiancée. About a month later he had his first panic attack and started avoiding social situations.

Psychological Causal Factors

Social phobias generally involve learned behaviors that have been shaped by evolutionary factors. Such learning is most likely to occur in people who are genetically or temperamentally at risk.

SOCIAL PHOBIAS AS LEARNED BEHAVIOR

Like specific phobias, social phobias often seem to originate from simple instances of direct or vicarious classical conditioning such as experiencing or witnessing a perceived social defeat or humiliation, or being or witnessing the target of anger or criticism (Harvey et al.,  2005 ; Mineka & Zinbarg,  1995  2006 ; Tillfors,  2004 ). In two studies, 56 to 58 percent of people with social phobia recalled and identified direct traumatic experiences as having been involved in the origin of their social phobias (Öst & Hugdahl,  1981 ; Townsley et al.,  1995 ). Another study reported that 92 percent of an adult sample of people with social phobia reported a history of severe teasing in childhood, compared to only 35 percent in a group of people with obsessive-compulsive disorder (McCabe et al.,  2003 ). Moreover, a recent laboratory study of people with social phobia revealed that they showed especially robust conditioning of fear when the unconditioned stimulus was socially relevant (critical facial expressions and verbal insults) as opposed to more nonspecifically negative stimuli (such as unpleasant odors and painful pressure) (Lissek et al.,  2008 ).

Öst and Hugdahl ( 1981 ) reported that another 13 percent of their subjects recalled vicarious conditioning experiences of some sort. One study interviewed a group of people with social phobia about their images of themselves in socially phobic situations and asked where those images had originated (Hackmann et al.,  2000 ). Ninety-six percent of these people remembered some socially traumatic experience that was linked to their own current image of themselves in socially phobic situations. The themes of these memories included having been “criticized for having an anxiety symptom” (e.g., being red or blushing), and having felt “self-conscious and uncomfortable in public as a consequence of past criticism” such as “having previously been bullied and called a ‘nothing’” (Hackmann et al.,  2000 , p. 606).

People with generalized social phobia also may be especially likely to have grown up with parents who were emotionally cold, socially isolated, and avoidant. Not surprisingly, such parents devalued sociability and did not encourage their children to go to social events. All these factors thus provided ample opportunity for vicarious learning of social fears (Harvey et al.,  2005 ; Morris,  2001 ; Rapee & Melville,  1997 ). Harvey and colleagues ( 2005 ) also found that many people with social phobia reported that the onset of their social phobia had occurred during a time when they were having problems with their peers such as not fitting in. Nevertheless, as with specific phobias, it is important to recognize that not everyone who experiences direct or vicarious conditioning in social situations, or who grows up with socially avoidant parents, or who has problems with peers, develops social phobia. This is because individual differences in experiences play an important role in who develops social phobia, as is the case with specific phobias.

DSM-5 criteria for: Social Anxiety Disorder (Social Phobia)

·  A. Marked fear or anxiety about one or more social situations in which the individual is exposed to possible scrutiny by others. Examples include social interactions (e.g., having a conversation, meeting unfamiliar people), being observed (e.g., eating or drinking), and performing in front of others (e.g., giving a speech).

Note: In children, the anxiety must occur in peer settings and not just during interactions with adults.

·  B. The individual fears that he or she will act in a way or show anxiety symptoms that will be negatively evaluated (i.e., will be humiliating or embarrassing; will lead to rejection or offend others).

·  C. The social situations almost always provoke fear or anxiety. Note: In children, the fear or anxiety may be expressed by crying, tantrums, freezing, clinging, shrinking, or failing to speak in social situations.

·  D. The social situations are avoided or endured with intense fear or anxiety.

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