PHOBIAS

Phobias are intense, persistent, unadaptive fears that are irrational/excessive. They are commonly classified into three groups: complex phobias, including agoraphobia (fear of public places, travel); social phobias (fear of social situations/scrutiny); and circumscribed phobias, including intense fears of insects, animals, heights, and enclosed spaces.

There are biological contributions to the development of some phobias, but the main determinants appear to be learned. Three main pathways to the acquisition of phobias have been identified. The conditioning acquisition of a phobia results from exposure to a traumatic stimulation or from repeated exposures to aversive sensitizing conditions. The second pathway is vicarious acquisition: direct or indirect observations of people, or of other animals, displaying fear. Among humans the transmission of fear-inducing verbal information is the third pathway. For a considerable time, explanations of the acquisition of phobias were dominated by the conditioning theory, which emphasized the importance of exposure to traumatic stimulation; recognition that fears can be acquired vicariously and/or by the direct transmission of information has led to a fuller account of the causes of phobias.

Important advances have been made in our ability to reduce phobias. Under controlled conditions, it is now possible to produce substantial and lasting reductions of phobias within a few sessions. It requires greater effort and far more time to reduce the complex and intense phobias, such as agoraphobia, but even these respond moderately well to treatment programs. There have been several attempts to explain how and when these methods of fear reduction achieve their effects, but each explanation has limitations.

Despite the many opportunities and circumstances in which phobias might develop, people acquire comparatively few; a satisfactory explanation of phobias must accommodate this fact as well as the appearance of phobias in a significant minority of the human population. It has also become apparent that people are more resilient than most psychologists have implied. Phobic patients who behave courageously during the course of treatment and soldiers who perform dangerous acts are notable examples of resilience.

Causes

The major features of the conditioning theory of phobias are as follows. Fears are acquired by a process of conditioning. Neutral stimuli that often are associated with a fear-producing or pain-producing state of affairs develop fearful qualities. They become conditioned phobic stimuli. The strength of the phobia is determined by the number of repetitions of the association between the pain/fear experienced and the stimuli, and by the intensity of the pain or fear experienced in the presence of the stimuli. Stimuli that resemble the fear-evoking ones also acquire phobic properties; that is, they become secondary conditioned stimuli. The likelihood of a phobia's developing is increased by confinement, by exposure to intensely painful or frightening situations, and by frequent associations between the new conditioned stimulus and the pain/fear. In an important extension, it has also been proposed that once objects or situations acquire phobic qualities, they develop motivating properties. A secondary fear drive emerges. Behavior that successfully reduces fear, notably avoidance behavior, will increase in strength.

Supporting evidence for the theory was drawn from six sources: research on the induction of fear in laboratory animals, the development of anxiety states in combat soldiers, experiments on the induction of fear in a small number of children, clinical observations (e.g., dental phobias), incidental findings from the use of aversion therapy, and a few experiments on the effects of traumatic stimulation.

The strongest and most systematic evidence was drawn from a multitude of experiments on laboratory animals. It is easy to generate conditioned fear reactions in animals by exposing them to a conjunction of neutral and aversive stimuli, usually electric shock. These fear reactions can be intense and persistent. Phobias can result from traumatic experiences in combat. In clinical practice, it is not uncommon for patients to give an account of the development of their phobias that can be construed in conditioning terms, and sometimes they can date the onset of the phobias to a specific conditioning experience (e.g., Lautch, 1971, on thirty-four cases of dental phobia). Di Nardo et al. (1988) found that nearly two-thirds of their subjects who were phobic toward dogs had experienced a conditioning event in which a dog featured, and in over half the dog had inflicted pain. It is important, however, that over two-thirds of a comparable group of subjects who were not frightened of dogs reported that they, too, had experienced a conditioning event, and that in over half of these instances the animal had inflicted pain.

These reports provide some support for the conditioning theory but also illustrate the fact that conditioning experiences, even those of a painful nature, do not necessarily give rise to a phobia or even to fear. Here, as in other instances, there was less fear than an unqualified conditioning theory would lead us to expect. Presumably the people who experienced conditioning events but failed to acquire a fear or phobia were "protected" by a history of harmless contacts with dogs. The roles that phobic patients attribute to direct and indirect experiences in generating their phobias differ with the content of the phobia, and of course the accuracy of their reports cannot be assured. In their analysis of 183 phobic patients, divided into six groups. Ost and Hugdahl (1985) found a range of attributions. For example, 88 percent of the agoraphobic patients attributed the onset of the phobia to a conditioning experience, but only 50 percent of those who were frightened of animals attributed the onset of their phobias to such an experience. Among the animal phobics, 40 percent traced the origin of the phobia to indirect experiences; such attribution was uncommon among the agoraphobics.

Although the importance of the phenomenon of acquired food aversions was not made evident until 1966, it is sometimes used to buttress the conditioning theory. The findings on this aversion also served to prompt radical rethinking of the concept of conditioning. Garcia and his colleagues were the first to demonstrate that strong and lasting aversive reactions can be acquired with ease when the appropriate food stimulus is associated with illness, even if the illness occurs many hours after eating (Garcia, Ervin, and Koelling, 1966). Given that the genesis of food aversions is a form of conditioning, if we also allow an equation between the acquisition of a food aversion and the acquisition of a fear, this phenomenon may have a bearing on the effect of the phobias.

If the acquisition of aversions is used to support the conditioning theory of phobias, it will have to take into account the temporal stretch of the phenomenon—that is, the delay that can intervene between the tasting of the food and the onset of the illness. Classical conditioning is expedited by temporal proximity between the stimuli, but food aversions can be easily and rapidly established even when there are long delays between the events. Hence, if the food aversion phenomenon provides support for a new or a revised conditioning theory of phobias, the temporal qualities of the conditioning processes must be deemphasized.

There are various arguments against acceptance of the conditioning theory of phobias as a comprehensive explanation. People fail to acquire phobias in what should be fear-conditioning situations, such as air raids. It is difficult to produce stable phobic or fear reactions in human subjects even under controlled laboratory conditions. The theory rests on the untenable equipotentiality premise (Seligman, 1972). The distribution of fears and phobias in normal and neurotic populations is difficult to reconcile with the theory. A significant number of people with phobias recount histories that cannot be accommodated by the theory. We also know that fears and phobias can be acquired vicariously, and that fears can be acquired by the reception of threatening verbal information. Fears, and possibly phobias as well, can be acquired even when the causal events are temporally separated (see Rachman, 1990).

Neoconditioning Concepts

The traditional insistence on the contiguity of the conditioned stimulus and the unconditioned stimulus as a necessary condition for the establishment of a conditioned response is mistaken. Rescorla has observed that "although conditioning can sometimes be slow, in fact most modern conditioning preparations routinely show rapid learning. One trial learning is not confined to flavor-aversion" (1988, p. 154). Apparently the associative span of animals "is capable of bridging long temporal intervals" (Mackintosh, 1983, p. 172). However, the learning must be selective; otherwise, animals would collect what Mackintosh has referred to as a "useless clutter of irrelevant associations." According to Mackintosh, the functioning of conditioning is to allow organisms to discover "probable causes of events of significance."

Given this new view, that conditioning is far more flexible and wide-ranging than was previously supposed, many of the objections to the conditioning theory of fear and phobias are weakened or eliminated. Although the application of neoconditioning concepts can shore up the conditioning theory, at the present stage the new view is too liberal. It lacks limits, and there is little left to disallow. In theory, almost any stimulus can become a conditioned signal for fear; but in practice people develop comparatively few phobias, and those we do acquire are confined to a limited range of stimuli. Phobias are not normally distributed.

Several sources of evidence suggest that phobias and fears can be acquired vicariously. Reports given by phobic patients, wartime observations, correlations between the phobias displayed by parents and children, laboratory demonstrations of conditioned fears, and research on animals have all provided some support for this view.

Verbal information can also generate a fear, and it is possible that in limited circumstances, it can even induce a phobia. Clinical evidence, especially that accumulating on the nature of panic disorders, suggests that phobias can be generated by information that is slightly or not at all threatening but is catastrophically misinterpreted by the recipient as being threatening.

Biological Determinants

The nonrandom distribution of human phobias, the high incidence of phobias of snakes and spiders and the low incidence of fears/phobias of motor travel, the remarkable speed with which certain objects can be transformed into objects of fear, and the common occurrence of irrational fears all point to the operation of nonlearned processes in the acquisition of fears and phobias. The main explanations fall into two classes: Some human fears and phobias are innately determined, or people are innately disposed rapidly to acquire phobias of certain specifiable objects or situations.

The most influential explanation is that set out by Martin Seligman, who argued, "The great majority of phobias are about objects of natural importance to the survival of the species … (human phobias are largely restricted to objects that have threatened survival, potential predators, unfamiliar places, and the dark)" (1972, p. 450). He postulates that certain kinds of fears are readily acquired because of an inherited biological preparedness. These phobias are highly prepared to be learned and, like other highly prepared relationships, "they are selective and resistant to extinction, and probably non-cognitive" (1972, p. 455).

The main features of prepared phobias are that they are very easily acquired (even by watered-down representations of the actual threat), selective, stable, biologically significant, and probably noncognitive. After some encouraging early laboratory demonstrations of fear preparedness in human subjects, subsequent research was disappointing because the phenomenon appeared to be too fragile. The laboratory effects appeared to be weak, transient, and difficult to reproduce. The plausibility of the concept has been weakened but not seriously damaged, and more powerful stimuli and more appropriate measures of fear responding are needed before the theory can be subjected to rigorous testing. The demonstration of preparedness in the development of phobias among laboratory monkeys encourages the belief that Seligman's theory retains considerable value. Mineka (1988) has shown that the fears induced in monkeys in laboratory conditions are intense, vivid, and lasting. The animals readily developed fears of snakes but showed little or no propensity to develop fears of biologically insignificant stimuli such as flowers.

Fear Reduction

Three powerful and dependable methods for reducing fear have been developed since the 1970s: desensitization, flooding, and therapeutic modeling. The common element in all three methods is the repeated and/or prolonged exposure of the fearful person to the stimulus or situation that provokes the fear (the exposure method). The selection of the appropriate fear-reducing technique depends on the nature of the phobia and the preference of the fearful subject, but all three methods are reliably robust. Fears of circumscribed stimuli, such as snakes or spiders, can be reduced fairly rapidly, even if they are intense and well established. The reduction or elimination of more complex fears, such as agoraphobia, requires greater effort and time. Despite these important practical advances, there still is no widely accepted explanation for the effects of these techniques.

See also:BEHAVIOR THERAPY; CONDITIONING, CLASSICAL AND INSTRUMENTAL; OBSERVATIONAL LEARNING; TASTE AVERSION AND PREFERENCE LEARNING IN ANIMALS

Bibliography

Di Nardo, P. A., Guzy, L. T., Jenkins, J. A., Bak, R. M., Tomasi, S. F., and Copland, M. (1988). Etiology and maintenance of dog fears. Behaviour Research and Therapy 26, 245-252.

Garcia, J., Ervin, F., and Koelling, R. (1966). Learning with prolonged delay of reinforcement. Psychonomic Science 5, 121-122.

Lautch, H. (1971). Dental phobia. British Journal of Psychiatry 119, 151-158.

Mackintosh, N. J. (1983). Conditioning and associative learning. New York: Oxford University Press.

Mineka, S. (1988). A primate model of phobic fears. In H. Eysenck and I. Martin, eds., Theoretical foundations of behaviour therapy. New York: Plenum Press.

Ost, L. G., and Hugdahl, K. (1985). Acquisition of blood and dental phobia and anxiety response patterns in clinical patients. Behaviour Research and Therapy 23, 27-34.

Rachman, S. J. (1990). Fear and courage, 2nd edition. New York: W. H. Freeman.

Rescorla, R. A. (1988). Pavlovian conditioning. American Psychologist 43, 151-160.

Seligman, M. E. P. (1972). Phobias and preparedness. Behavior Therapy 2, 307-320.

Stanley J.Rachman