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Aetiology of phobias

Psychoanalytic models

According to Freud, phobias act as a defence against the anxiety experienced when impulses formed by the id are repressed – resulting in a displacement of the repressed feelings onto the object or situation with which it is symbolically associated. These become phobic stimuli and the individual is able to avoid dealing with their repressed conflicts by avoiding them. These conflicts often involve childhood trauma or conflict. The most famous case of a phobia discussed by Freud is that of Little Hans. Hans was a 5-year-old boy who was afraid of horses, and avoided leaving the house for fear of being bitten by one. He also developed a specific fear of the blinkers and muzzles on horses’ faces. Freud considered his fears to relate to the Oedipus complex, and that he was having sexual fantasies about his mother and feared his father’s retaliation. He therefore displaced the fear of his father onto horses who reminded him of his father. A more prosaic explanation for these fears may have been his witnessing an incident in which a horse fell down in the street in front of him. Another psychodynamic interpretation, in which the feared object or behaviour is seen as symbolic of other fears or issues (agoraphobia as a response to feeling trapped within a marriage) may be less sexually charged than Freud’s interpretation but of relevance to more modern psychodynamic therapists.

Behavioural models

Early behavioural models of phobias considered them to result from conditioning experiences, in which the inappropriately feared object or situation was associated with the experience of fear at some time in the past. The conditioning process can be so powerful when acute fear is experienced, that this association need happen only once to result in a long-term fear response that is difficult to extinguish. Being in a car crash, for example, may result in a phobic reaction to being in a car, and subsequent avoidance of being in a car or driving. This response has three components:

a behavioural element involving avoidance or escape from the feared object

high levels of physiological arousal evident through a variety of symptoms including physical tension, increased startle response, tremor or sweating and driven by the sympathetic nervous system the emotion of anxiety and fear.

The classical conditioning model of phobias is adequate in its description of the process of acquisition of anxiety and phobias. However, it is less able to explain why they are maintained over long periods, as repeated exposure to the feared object or situation in the absence of any negative consequences should lead to a reduction of anxiety through the process of extinction. Mowrer’s  two-factor theory combined both classical and operant processes to provide an explanation of this phenomenon. He noted that once a phobic response is established through classical conditioning processes, the affected individual tends to avoid the feared stimulus. This has two consequences. First, it prevents the classical conditioning process of extinction, as the individual does not experience the conditioned stimulus under conditions of safety. Second, because avoidance itself produces feelings of relief (i.e. it is reinforcing), the avoidance response is strengthened by operant conditioning processes. In this way, anxiety is potentially maintained over long periods.

A cognitive behavioural model

In response to these concerns, more recent models of the aetiology of phobias have retained the conditioning processes of the early models but added a number of other processes. The most important of these is the addition of cognitive variables as mediators of both the acquisition of a phobias and their potential time course (Davey 1997). Factors that may infl uence the acquisition of phobias include:

The degree of familiarity with the feared stimulus. The more trauma-free associations an individual has had with a particular stimulus, the less likely they are to develop a phobia if that stimulus subsequently becomes associated with high levels of fear: a process known as latent inhibition. Conversely, the more negative emotions are associated with a particular stimulus prior to a traumatic event, the more likely an individual is to develop a phobia.

Information from other people or observation of someone else expressing high levels of fear in the context of a particular stimulus. The latter process is known as vicarious learning and provides one explanation for the high prevalence of the same phobias in some families.

Biological/evolutionary model A second infl uential theory used to account for the non-random distribution of phobias is known as preparedness theory. Seligman (1971) proposed that some phobias or fears are more easily acquired as a result of their evolutionary usefulness than others. He contended that at some time in our evolutionary history it was benefi cial to have a fear of potentially dangerous stimuli such as snakes, small animals, and so on – stimuli he termed ‘phylogenetically relevant cues’. As a result, we may be hardwired, or biologically prepared, to react fearfully to stimuli that were once threatening to prehistoric man. Note that Seligman did not suggest we have an inborn fear of snakes, spiders, and so on. Rather he suggested that we acquire fear to such stimuli more easily following some form of conditioning experience than we do to others. The theory has four key predictions (Merckelbach and de Jong 1999):

The most prevalent phobias should be to stimuli that were potentially dangerous in a pretechnological age: this does seem to be the case.

Fear of these stimuli is easily acquired (and more easily than other phobias): again, this may the case. Marks, for example, gave an example of a woman who was looking at a picture of a snake at the time she was involved in a car accident. She become phobic to snakes, but not to cars.

Because of their biological signifi cance, they are non-cognitive.

They resist extinction: experimental work by Öhman and colleagues found that once a conditioned response to phylogenetically relevant stimuli was established in the laboratory, it took longer to extinguish than other conditioned phobias. Accordingly, although not all the evidence is strongly supportive of the model, the consensus seems to be that some evolutionary/genetic processes may be involved in the acquisition of phobias.

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