Anxiety Disorders: Social and Specific Phobias
The experience of fear and the related emotion of anxiety are uni-versal and familiar to everyone. Fear exists in all cultures and ap-pears to exist across species. Presumably, the purpose of fear is to protect an organism from immediate threat and to mobilize the body for quick action to avoid danger. Emotion theorists consider fear to be an alarm response that fires in the presence of imminent threat or danger. The function of the primarily noradrenergic me-diated fear response is to facilitate immediate escape from threat (flight) or attack on the source of threat (fight). Therefore, fear is of-ten referred to as a fight-or-flight response. All the manifestations of fear are consistent with its protective function. For example, heart rate and breathing rate increase to meet the increased oxygen needs of the body, increased perspiration helps to cool the body to facilitate escape, and pupils dilate to enhance visual acuity.
Anxiety, on the other hand, is a future-oriented mood state in which the individual anticipates the possibility of threat and experiences a sense of uncontrollability focused on the upcom-ing negative event. In the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM-IV-TR) (American Psychiatric Association, 2000), anxiety is defined as “the apprehensive anticipation of future danger or misfortune accompanied by a feeling of dysphoria or somatic symptoms of tension” (p. 820). If one were to put anxiety into words, one might say, “Something bad might happen soon. I am not sure I can cope with it but I have to be ready to try”. Anxiety is primarily medi-ated by the gamma-aminobutyric acid-benzodiazepine system.
Despite evidence that fear and anxiety are mediated by differ-ent brain systems, anxiety and fear are related, which makes sense ethologically. Experiencing anxiety after encountering signals of impending danger seems to lower the threshold for fear which is triggered when danger actually occurs (e.g., being attacked by a mugger or almost being hit by an automobile). Anxiety leads to a shift in attention toward the source of danger so that individuals be-come more vigilant for relevant threat cues and therefore are more likely to experience fear in the face of perceived immediate threat.
Fear and anxiety are not always adaptive. At times, the re-sponses can occur in the absence of any realistic threat or out of proportion to the actual danger. Almost everyone has situations that arouse anxiety and fear despite the fact that the actual risk is minimal. It is not unusual to become anxious before a job interview or a speech. Many individuals feel fearful when exposed to situa-tions such as dental visits, seeing certain animals, or being at cer-tain heights. For some people, these fears reach extreme levels andmay cause significant distress or impairment in functioning. It is at this point that what we typically refer to as shyness and fearfulness might meet diagnostic criteria for social phobia or specific phobia, respectively (see DSM-IV-TR Criteria 300.23 and 300.29).
As discussed later, phobias are the most common of the anxiety disorders and among the most common of all mental dis-orders. However, despite the frequency with which phobias occur in the general population, they have tended to be relatively ignored by clinicians and researchers. The introduction of social phobia to the diagnostic nomenclature has led to a slow but steady increase in research on the disorder, so that social phobia has now become a more popular topic of study among researchers on anxiety disor-ders. In addition to being widespread, social phobia is associated with significant functional impairment. Also, social phobia often presents comorbidly with other mental disorders. Despite the high prevalence rate and significant impairment, generalized social phobia is rarely diagnosed or treated in a primary care setting
With respect to specific phobias, the lack of attention is proba-bly due to several factors. First, many physicians and researchers may view specific phobias to be less severe than other disorders, therefore warranting less attention. In addition, few individuals with specific phobias present for treatment, and the ones who do seek help tend to differ from untreated individuals with phobias with respect to the number and types of specific phobias. As with social phobia, there has been an increase in attention paid to specific phobias, along with increased recognition that these phobias can interfere seriously with an individual’s ability to function. It is not unusual for flying phobias to lead individuals to refuse job promotions that involve travel or to avoid visiting distant family members. Likewise, individuals with insect phobias may avoid being outside during the summer.
Historically, the etiology of phobic disorders was typically ex-plained from a psychoanalytic perspective. Although the defense mechanism of repression is typically used to protect the individ-ual from experiencing the anxiety (and the underlying conflict), when repression is insufficient the ego must use additional de-fense mechanisms. In the case of individuals with phobias, Freud proposed that displacement of the anxiety to a less relevant object or situation occurs (such as a dog or some other animal), so that the feared object is used to symbolize the primary source of the conflict. Patients with phobias use avoidance further to escape the effects of the anxiety. Although Freud’s theory was once influential, its impact on current thinking among researchers has waned. Rather, most current research on psychological factors in the development of phobias has tended to focus on conditioning and information-processing theories and their interaction with neurobiological processes.
Emotions are “contagious”. That is, we learn to respond to stim-uli, in part, by observing other people’s responses and also by our own experiences in these situations. In other words, we come to fear dangerous situations easily. This is important from anethological perspective because our ancestors who could learn to fear threatening objects or situations easily were more likely to survive and pass these genes to their offspring. This inherited tendency to learn to experience fear in particular situations is the basis of conditioning models of phobia development.
Rachman’s Pathways to Fear Development Rachman (1977) proposed three pathways to the development of fear. The first of these is direct conditioning, which typically involves the experi-ence of being hurt or frightened by the phobic object or situation. Examples include being involved in an automobile accident, being humiliated in front of a group, falling or almost falling from a high place, or fainting at the sight of blood. Rachman’s second pathway is called vicarious acquisition, which involves witnessing some traumatic event or seeing someone behave fearfully in the pres-ence of a phobic situation. For example, a child might develop a fear of snakes after seeing her father behave fearfully around snakes, or someone might develop a fear of public speaking after seeing another individual heckled by the audience during a pres-entation. For the third pathway, Rachman proposed that fears can develop through informational and instructional pathways. It is not surprising that individuals might develop flying phobias, given the frequency with which plane crashes are reported in the news. Similarly, a child might develop a fear of heights if his parents frequently warned him of the dangers of being near high places.
In addition to these pathways, Rachman acknowledged the role of biological constraints on the development of fear. Of particular relevance is the fact that fears are not randomly distrib-uted. To explain this observation, Seligman (1971) proposed that organisms are predisposed to learn certain associations and not others. Seligman called his theory “preparedness” and hypoth-esized that individuals are “prepared” to develop some associa-tions that lead to fear and not others. For example, an individual might be more likely to develop a fear of dogs after being bitten than to develop a fear of flowers after being pricked by a thorn. Seligman proposed that these associations evolved through natu-ral selection processes to facilitate survival.
Evidence for the theory of preparedness is mixed. Although some authors have concluded that the studies to date do not support preparedness, it may be argued that these studies have not adequately tested the theory. Most studies examining preparedness have attempted to associate dangerous objects (e.g., snakes) and nondangerous objects (e.g., flowers) with an aversive electrical shock and have found few differences in the subsequent development of fear. However, preparedness predicts that some “associations” are more difficult to establish than others, not that some “objects” are more easily feared than others. The theory does not necessarily predict that shock should be more easily as-sociated with snakes than with flowers. A more appropriate ex-periment might be to compare the effects of a minor snakebite to the effects of being pricked by a thorny flower on the develop-ment of fear of each object. In any event, there is now strong evidence that conditioning processes play an important role in the development of phobic disorders.
Numerous studies have examined the prevalence of Rach-man’s three pathways to fear development. Most of these studies have focused on the development of specific phobias, although a few studies included social phobia groups. The majority of stud-ies have found support for the model, indicating that both direct and indirect forms of phobia acquisition occur frequently across a wide range of phobias. However, numerous people report onsets that are unrelated to these pathways (e.g., “I have had this fear foras long as I can remember” or “I have always had this fear”). Overall, it appears that direct and indirect methods of fear devel-opment are relatively common, although the frequency of these onsets varies greatly across studies for a variety of reasons.
Despite the prevalence of direct and indirect condition-ing events and informational onsets, it appears that they are not the whole story. In fact, studies have begun to include normal comparison groups and have found that these events are equally common in individuals who do not have phobias. Ultimately, to answer the question of how phobias begin, we must discover the variables that lead only certain individuals to develop phobias after experiencing conditioning events or receiving information that leads to fear. For example, several investigators have found that a tendency to feel “disgust” in response to certain stimuli may be important in the development of some animal phobias and blood phobias. In addition, heightened disgust sensitivity in parents has been found to predict fear of disgust-relevant animals (e.g., snakes, mice, slugs and cockroaches) in children. Several other variables have also been suggested as mediating factors in the development of fear. Stress at the time of the event may make individuals more likely to react fearfully. In addition, previous and subsequent exposure to the phobic object may protect an in-dividual from the development of a phobia. For example, some-one who grew up around dogs may be less likely to develop a phobia after being bitten than someone who has spent little time around dogs. The context of the event may also influence the re-action. For example, being with another supportive individual at the time of the trauma may protect an individual from developing fear. Finally, a number of individual difference variables such as perceived control, trait anxiety and various personality factors may influence an individual’s likelihood of developing a phobia after a conditioning event. In fact, there is evidence that person-ality factors and parenting styles may be especially relevant to the development of social phobia.
It has been proposed that a fourth nonassociative path-way be added to Rachman’s three associative pathways to fear development. Nonassociative fear models propose that a limited number of fears are not acquired by conditioning or other learn-ing processes. Rather, these evolutionary adaptive fears are pro-posed to be innate or biologically determined. This is similar to preparedness theory, however, it maintains that fears are acquired through a learning or conditioning process and that some fears are more easily learned than others. The nonassociative pathway to fear acquisition helps to explain a number of research find-ings that run counter to associative models of fear development, including the nonrandom distribution of common fears, and the emergence of some fears without any prior specific associative learning experiences (i.e., direct conditioning, vicarious condi-tioning, or informational transmission).
Personality Variables It appears that at as early as 18 months of age children differ with respect to their tendency to interact with other individuals, toys and objects. Although about 70% of children are somewhat exploratory in these situations, about 15% of children are extremely exploratory, and the remaining 15% are quite shy and withdrawn. The behavior exhibited by the shy and withdrawn children has been called “behavioral inhibition” and has been proposed to be a predisposing factor in the development of social phobia and other anxiety disorders. One study found that the prevalence of social phobia was significantly greater (17%; N 5 64) in children with behavioral inhibition than without (5%; N 5 152) (Biederman et al., 2001). In addition, compared with nonanxious individuals, patients with social phobia describe their parents as having 1) discouraged them from socializing; 2) placed undue importance on the opinions of others; and 3) used shame as a means of discipline. Other predictors of the develop-ment of social phobia include a childhood history of separation anxiety, self-consciousness or shyness in childhood and adoles-cence, and a low frequency of dating in adolescence.
Perfectionism is another personality variable that has been associated with social phobia. Although several other anxiety disorders have also been associated with perfectionism, concern about making mistakes and a perception of having critical par-ents are highest among individuals with social phobia compared with individuals with other anxiety disorders (e.g., panic disor-der, obsessive–compulsive disorder, or specific phobia).
Cognitive Variables Numerous studies have examined the role of cognitive variables in social and specific phobias and have consistently found that individuals with these disorders exhibit attentional and attributional biases regarding the phobic object or situation. In studies of information processing, people with social and specific phobias devote more attention to threat-related infor-mation than do nonphobic individuals. They also show percep-tual and cognitive distortions consistent with their phobias. For example, individuals with snake or spider phobias tend to over-estimate the degree of activity in the feared animal before treat-ment but not after treatment. Likewise, people with social phobia tend to rate their own performance during public speaking more critically than do nonphobic control subjects. Furthermore, the discrepancy between self-ratings and observer ratings is greater for people with social phobia than control subjects. In addition, individuals with social phobia tend to report more negative self-evaluative thoughts and underestimate their performance when interacting with others relative to nonanxious subjects. More re-cent research has found that compared with nonanxious individu-als, individuals with social phobia are more likely to experience negative imagery and to take an observer’s point of view (i.e., see themselves from an external perspective) when exposed to feared social situations. Other research has found that social phobia is as-sociated with impaired thought suppression affecting both social phobia-related stimuli as well as nonsocial phobia-related stimuli. Although it is clear that cognitive biases exist in individuals with phobias and that attentional and attributional biases improve after effective treatment, it is not known whether the cognitive biases exhibited by patients contribute to the development of the fear or whether they are simply a manifestation of the fear.
Specific phobias and social phobia tend to run in families. It ap-pears that being a first-degree relative of an individual with a specific phobia puts one at a greater risk for a specific phobia compared with first-degree relatives of never mentally ill con-trols (31% versus 11%). However, the particular phobia that is transmitted is usually different from that in the relative, although it is often from the same general type (e.g., animal, situational). Furthermore, relatives of people with specific phobias are not at increased risk for other types of anxiety disorders (including so-cial phobia) or subclinical fears. There is no increased risk among relatives of people with social phobia to develop other anxiety disorders. A recent study found that in comparison to probands in a comparison group, the relative risk for generalized social phobia and avoidant personality disorder were tenfold for first-degree relatives of probands with social phobia.
Of course, the existence of a disorder in multiple family members does not necessarily imply genetic transmission. Family members often share learning experiences and other environ-mental factors. To establish a genetic relationship among family members with a particular disorder, twin studies, adoption studies and molecular genetics studies are typically conducted. Currently, there are no adoption or molecular genetics studies of social or spe-cific phobias, and twin studies have yielded conflicting results.
Although there are conflicting findings on whether there is a general genetic factor (influencing risk for any anxiety dis-order) or a specific genetic factor (influencing risk for specific anxiety disorders such as specific and social phobias), some gen-eral conclusions can be made. In the case of social phobia, there seems to be a moderate (based on the strength of the correlations from twin studies) disorder-specific genetic influence combined with specific and nonspecific environmental influences. In the case of specific phobia, evidence supports a disorder-specific ge-netic contribution combined with disorder-specific environmen-tal influences (e.g., traumatic conditioning experiences involving the phobic object or situation).
Although the nature of the genetic contribution has yet to be specified (a low threshold for alarm reactions or vasovagal re-sponses is one possibility), specific and social phobias may be related to personality factors that have been found to be highly heritable. Two traits that may be relevant are neuroticism (or emotionality) and extroversion (or sociability). Average heritabil-ity estimates for these traits are about 50% across a wide range of genetic studies. Emotionality probably predisposes individu-als to develop a range of anxiety and mood disorders whereas sociability may be most relevant to social phobia. Furthermore, certain phobias may have other specific genetic contributions. Up to 70% of individuals with blood phobia report a history of faint-ing on exposure to blood. It has been suggested that an inherited overactive baroreflex may contribute to the high rate of familial transmission of blood phobias.