Behaviourist explanation of Phobias Lecture PDF

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Behaviourist explanation of Phobias Lecture notes...

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Behaviourist explanation of Phobias Mowrer’s ‘two-factor’ approach. Mowrer believed that both classical and operant conditioning are involved in acquisition and maintenance of phobias.

 Classical conditioning As we have seen with Little Albert and other studies, we initially learn fear by association. Classical conditioning therefore explains how we acquire the fear.  Operant conditioning Avoiding the fear-provoking stimulus then prevents us from unlearning the fear so as a result the fear is not extinguished. Operant conditioning therefore explains why a phobia is maintained.

Acquisition Phase

Neutral stimulus: rat Unconditioned stimulus: loud noise Unconditioned response: fear of noise

Neutral stimulus and unconditioned stimulus paired together here to edit.

Neutral stimulus (rat) has become the conditioned stimulus and now evokes the conditioned response: fear of rat.

Watson and Raynor (1920) classically condition a fear of white rats in an 11 month old boy, Albert. Over a period of weeks each time he plays with a toy white rat an iron bar is struck. At first this causes hesitation when dealing with the rat and eventually after 10 days or so (the third trial) he becomes distressed when the rat is seen. Worth mentioning is that the fear was immediately generalised to a toy white rabbit (sufficiently similar in appearance to the rat to illicit the response) whereas fear of cotton wool and of a toy dog was not so pronounced (evidence of discrimination). Clearly the ethics of the study can be questioned. Watson & Raynor were both doctors so would have been aware of the long term effects their procedure may have had. It is clear when reading their report that they did consider the consequences in advance but went ahead on the grounds that this was no more distressing than the experiences he was likely to encounter in the real world. It had been their intention to treat Albert’s condition with a number of experimental techniques, including reconditioning in

which he would have been given ‘candy’ each time the rat was presented. His mother removed Albert from the experiment before this could be done.

Operant conditioning Negative reinforcement. (Reminder: negative reinforcement is the removal of something unpleasant. Being a reinforce, it makes a behaviour more likely to be repeated). Avoiding a situation or object that causes anxiety or fear is seen by behaviourists as being rewarding in itself. If you suffer from arachnophobia then avoiding spiders will result in you suffering less anxiety. As a result you will behave in a way that keeps you clear of spiders. Unfortunately this means that your fear will not be extinguished since the only way to lose a behaviour, in behaviourist terms, is by unlearning the association between fear and the stimulus that causes it. here to edit. Evaluation of the behaviourist explanation There is some evidence to support the theory, particularly the case of Little Albert who clearly did acquire a phobia via classical conditioning and who did generalise it, as predicted by behaviourists, to similar objects such as rabbits. Some successful treatments for phobias are based on behaviourist theories. Barlow & Durand (1995) reported that 50% of people with a phobia for driving could remember a specific incident that had triggered their fear, again supporting the theory that phobias are learned. However, about 50% of people with phobias cannot recall a specific event that triggered the fear. DiNardo et al (1988) reported that only about half of all people that have had frightening experiences of dogs go on to develop a phobia of dogs. This individual difference in susceptibility to acquiring phobias suggests a possible diathesis-stress predisposition to phobias. Some people, courtesy of their genes are more likely to develop phobias than others.

Biological preparedness Seligman (1971) believes we are predisposed to acquire some phobias rather than others. Learning to be frightened of snakes and spiders might once have conferred an evolutionary advantage. Therefore, the extent to which we learn phobias may be determined by our biology! Ohman et al (1975) used classical conditioning to induce a fear of either snakes and spiders or houses and flowers. They did this in the time honoured way of pairing the stimulus with electric shocks (like my number 3). After a shock-free period the fear for houses and flowers extinguished (died out) very quickly. The fear of snakes and spiders persisted. This suggests that we may be predisposed to acquire phobias to situations or objects that are life-threatening. As always the theory is reductionist (explains a complex behaviour in very simple terms) and ignores biological or genetic factors. There are also cognitive symptoms to phobias such as the cognitive distortions and irrational beliefs that simply cannot be explained by the behaviourist model....