Behavioural approach to treating phobias : Systematic Desensitisation (3)

Systematic Desensitisation

• The most commonly used behavioural therapy to treat phobias is known as systematic desensitisation (SD)

• SD takes place over weeks or even months as it a gradual, stage-based process, putting the patient in charge of their own progress

How does SD work along the principles of classical conditioning ?

• The phobic stimulus was originally a neutral stimulus, i.e., before it became the conditioned stimulus, triggering the conditioned fear response

• By reversing the mechanisms of classical conditioning, it is possible for the conditioned phobic stimulus to revert to being the neutral stimulus again, i.e., it produces no fear response in the person

• By gradually exposing the phobic person to the phobic stimulus, a process of 'unlearning' happens - they are conditioned to view the stimulus without fear

What are the three stages of systematic desensitisation ?

The three stages of systematic desensitisation are: 

• Anxiety Hierarchy

  • The patient and therapist work together to construct an anxiety hierarchy, which is a list of situations that involve the phobic stimulus from least to most frightening, e.g. for a phobia of spiders:

Stage 1	Imagine a spider; think of what it looks like
Stage 2	Look at a picture or pictures of spiders
Stage 3	Enter a room with a spider in a glass box
Stage 4	Look at the spider in the glass box
Stage 5	Hold the glass box with the spider inside
Stage 6	Watch someone else hold the spider
Stage 7	Allow the spider to walk close/on to you
Stage 8	Hold the spider

• Relaxation

  • Breathing exercises help to calm the patient physiologically by slowing down and controlling the breath

  • Visualisation involves the patient placing themselves, mentally, in a relaxing, calming environment, e.g., a beach or a meadow

  • Drug therapy may also be used as a biological treatment, e.g., diazepam

• Exposure

  • Whilst in a relaxed state the patient is exposed to the phobic stimulus starting at stage 1 of the anxiety hierarchy

  • The patient moves up the hierarchy stage by stage, continually checking for signs of panic and slowing down if necessary

  • The aim of exposure is for the patient to move to the top of the hierarchy, whilst remaining relaxed and in control

Strength 1 Evaluation of Systematic Desensitisation

• SD is supported by research, e.g.,

  • Gilroy et al. (2003) studied 42 patients who had SD as a treatment for their spider phobia over three 45-minutes sessions

    • She found that at both 3 and 33 months they were less fearful and more in control of their phobia compared to the control group, who had not had any SD therapy

    • This supports the effectiveness of SD as a treatment for phobias

Strength 2 Evaluation of Systematic Desensitisation

• SD is successful with patients who have a vivid imagination and can imagine their phobia which means that for some phobias it is a validtreatment method

Limitation 1 Evaluation of Systematic Desensitisation

• 
  SD does not treat the cause of the phobia, only the behaviour it results in

  • This inability to address the cause of the phobia means that the phobia may return or another phobia may replace the original phobia

    • Thus SD has limited usefulness 

Limitation 2 Evaluation of Systematic Desensitisation

• Some patients may struggle to deal with the phobia outside of the therapy sessions

  • They may not be able to apply what they have learned to real, everyday situations, particularly without guidance from the therapist

    • This reduces the external validity of the theory behind the treatment

  • An alternative, perhaps more effective treatment would be a combination of a biological (e.g. drug therapy) and behavioural (e.g., SD) treatment