History and Development of Cognitive Behaviour Therapy CBT

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The foundations of cogitive behaviour therapy (CBT) can be traced back to the early part of the 20th Century. The Darwinian view popular at this time suggested the continuity between man and lower animals, and allowed 'Animal Models' of behaviour to be applied to theories of how psychological problems develop and are maintained. i.e. The main assumpotion being that principles derived from studying animal learing could be applied to man.

Early research identified two principles of animal learning crucial to the development of CBT.

Classical Conditioning

This principle was derived from the work of pavlov and other Russian physiologists. They conducted experiments with dogs where a bell was rung immediatley before food was given. After this was repeated a few times, the dogs began to salivate when theyheard the bell, even before the food was presented.

These early russian investigators also found that emoptional responss such as fear could be conditioned. e.g. pairing a red light with an electric shock produced the fear response suggesting anticpation of pain, without the electric shock being given.

Operant Conditioning

This principle was derived from the work of Thorndike, Tolman and Guthrie in the USA. In a series of research studies they found that if a behaviour was consitenly followed by a reward it was more likely to occur; similarly if a behaviour was consitenly followed with unpleasant outcomes it would occur less frequenlty. This is known as 'The Law of Effect'.

These two conditioning paradigms, invaluable in teh development of Behavior Therapy were later integrated by practitioner such as Hull and Mowrer. Particularlly important was Mowrers work on the 'Two-Factor Model/ which encompasses both classical and operant  components to account for the development and maintenance of fear responses. He suggested that fear of specific stimuli is acquired through CC and that as fear is aversive the animal learns to reduce it by avoiding the conditioned stimuli.

Early application of behavioural principles

Watson and Raynor (1920) 'LittleAlbert'. They Found they were able to produce a conditioned anxiety response in this 11 month old infant by pairing the appearance of a rat with a loud noise.

Mowrer and Mowrer (1938) enuresis. They viewed enuresis as a failure of the person to wake up in response to bladder distension. They paired bladder distension (the onset of urination) with the sound of a bell (the bell and pad method) which awoke the person, produced sphincter contraction and stoppped urination. After several trials bladder distension alone produced sphincter contraction.

Wolpe (1950) began to report work on 'experimental neuroses in cats. He was particularly interested in the production of conditioned fear e.g. if an animal expereienced a small shock when it approached food, subsequently the fear could be elicited by other situations that where similar to the situation in which the shockhad been delivered. Since feeding was inhibited by conditions which elicited the symptoms of the experimental neurosis, this suggested to him that conditioned fear and feeding were mutually antagonisticor reciprocally inhibiting. This lead to the idea that feeding might be used to reduce the anxiety elicited by specific situations.

Wolpe proposed that fear reduciton could generally be accomplished by the simultaneous presentation of anxiety provoking stimuli and stimuli evoking a response antagonistic to anxiety (The Reciprocal Inhibitor), provided that the antagonist response was the stronger of the two. In order to ensure that the inhibitor was stronger, the anxiety provoking stimuli were presented in a graded way, on a hierarchy, beginning with with a mildly anxiety provoking stimuli and progressing.

In applying his findings to humans Wolpe considered three main repsonses which might act as resiprocal inhibitors: sexual repsonses, assertive responses, and progressive muscular relaxation.

The most widely adopted of these was relaxation. In Wolpes method the patient was taught relaxation, then encouraged to progress step by step through a hierarchy of feared situations while maintaining the relaxation repsonse in order to reciprocally inhibit the fear repsonse. Initially Wolpe used real life situations (in vivo) but later changed to imaginal exposure. This procedure became known as systematic desensitisation.

Wolpes contribution to behaviour therpay was considerable not least because he was reporting his work at a time when the efficacy of psychoanalytic approaches was undergoing critical appraisal.Eysenk (1952)published a contoversial review in which he argued the improvemnt rates achieved by psychotherapy were no higher than would be expected by spontaneous recovery.

Also at this time a group of behaviour therpaists at the Maudsley hospital hels a series of seminars demonstrating the application of conditioning principles to psychological problems.

The early sixties saw the gradual application of behavioural problems beyond fear reduction - behavioural medicine, aversion therapies ,sexual and marital therapies and the application of operant approaches to problems of mentally handicapped people and psychotic patients. The work with severely impaired psychiatric patients was particuarly influential becuse it demonstrated that psychological intervention could be effective in patients (especially those with chronic schizophrenia) not previously regarded as amenable to such approaches.