Compared to Freud’s analysis of phobias the behavioral account is testable and furthermore, backed up by many case studies and experimental evidence (Davidson & Neale, 1990). Watson and Rayner (1920, as cited in Davey, 1997) showed that classical conditioning could produce phobic avoidance of a pet rat (CS) if it was paired with noisy striking of a metal bar (UCS). The behavioral theory has subsequently been expanded to incorporate the possibility of the phobia being learnt through vicarious experience (Bandura & Rosenthal, 1966, as cited in Davidson & Neale, 1990). However, Seligman’s (1971, as cited in Davey, 1997) theory of Preparedness incorporated these findings with Marks’ (1969, as cited in Davidson & Neale, 1990) research suggesting that humans tend to be afraid of certain objects, whether at a phobic or normal level. Seligman (1971) suggested that evolutionary pressures have predisposed humans to be afraid of objects and situations that would have threatened the survival of our ancestors (those that are “phylogenetically relevant”). These stimuli, when pared with a noxious event would easily produce a phobia. This could be interpreted as an extension of normal fear as it is an exaggerated response to stimuli that humans are predisposed to fear and that are also feared at socially acceptable (normal) levels in the non-clinical population.
One particular feature of certain phobias that is hard to reconcile with the preparedness account is the fear people develop towards spiders and small animals even though they are not phylogenetically relevant. Matchett and Davey (1991) suggest that people who fear these stimuli also have heightened disgust sensitivity. Moreover, Webb and Davey (1992, as cited in Davey, 1997) found that fear could be linked causally to disgust as viewing a repulsive medical operation increased subsequent participant fear ratings of spiders and snakes. If disgust has a causal role in certain phobias it suggests that factors other than a pure extension of normal fear may come into play in the etiology of these disorders. However, this can be reconciled with the idea of normal fear and the preparedness paradigm as Matchett and Davey (1991) propose that this disgust is actually indicative of a phylogenetically relevant fear of contamination and disease.
Although within the preparedness account of phobias, classical conditioning can be seen as a process by which normal fear is developed into a pathological condition, an operant conditioning model suggests a very different mechanism. In a case study of a school phobic Lazarus, Davidson and Polefka (1965) found that the disorder was not purely the result of an exaggerated normal fear. Instead, during therapy when anxiety of the school situation had markedly decreased, operant reinforcers such as attention from the parents and therapists maintained the phobic avoidance.
Although conditioning, whether operant, classical or vicarious is frequently put forward as part of a phobia acquisition mechanism, aspects of certain phobias may not be related to these paradigms or even to a concept of fear. Blood-Injection-Injury, although classed as a simple phobia, has often been considered atypical due to the unusual symptom of emotional fainting at the sight of the phobic object (Page, Bennett, Carter, Smith & Woodmore, 1997). Evolutionary hypotheses interpret this as a reflex reaction, which could be similar to that of freezing or death feigning in animals (Marks, 1988; Marks & Nesse, 1994, as cited in Davey, 1997). Equally, it could be seen as a protective mechanism against blood-loss on injury as fainting slows the circulation (Thyer, Himle & Curtis, 1985; Barlow, 1988, as cited in Davey, 1997). Both of these evolutionary hypotheses suggest a non-fear element to the symptoms of certain phobias and so cannot be seen as an extension of normal fear.