Depression - Comparing treatments [Biological, behavioural and cognitive]

Depression is an affective (mood) disorder which affects approximately one in 5 older people, and thus being able to treat depression is obviously very important. 

The biological approach to treating depression

The biological approach assumes that all behaviour has a biological cause, and thus it targets biology when attempting to treat depression. As many biological psychologists believe that depression is caused by neurotransmitter dysfunction, the treatment for depression aims to target this through a form of therapy called drug therapy. 

Drug therapy is specific to the type of disorder that is being treated; anti-psychotics for psychotic disorders, anti-anxiety medication for anxiety disorders, and anti-depressants for affective disorders. 

Anti-depressants aim to treat depression by raising levels of certain neurotransmitters such as serotonin, as low levels of serotonin have been associated with depressed mental states. 

Study: Karp and Frank (1995) carried out a review article on the effectiveness of drug therapy in treating depressed women. Meta-analysis  (combined analysis) of nine pieces of research featuring a total of 520 women with depression showed that adding cognitive therapy to drug therapy was no more effective than merely prescribing anti-depressants. This suggests that drug therapy for depression is sufficient treatment for depression without other components. 

The behavioural approach to treating depression

The behaviourist approach works on the basis that if behaviour is learned, it can also be unlearned, often through the use of Cognitive Behavioural Therapy (or CBT).

The cognitive element of CBT essentially asks the client undergoing therapy to keep a diary of thoughts and beliefs, and then the therapist will work through them in order to challenge negative thought patterns. The behavioural element, focussed on behavioural activation, features the client and therapist planning pleasurable activities (working on the basis of classical conditioning) and providing rewards for non-depressed activities such as being sociable and active (working on the basis of operant conditioning). Thus, the client learns to associate "non-depressed" activities with pleasure and will therefore be more likely to continue in order to get the positive reinforcement of pleasurable activities and feelings. 

Study: Lewinson (1990) refers to the CBT programme of "coping with depression", a skills based programme where people with depression work together in small-groups to relieve their depression through learning skills such as assertiveness, mood monitoring, relaxation and conflict resolution. It used a sample of 69 depressed self-selected adolescents from Oregon, US, who were split into 3 conditions: only adolescent received training, both adolescent and parents received training, and a control group who were put onto a waiting list for therapy. Note that whilst the adolescents received the "coping with depression" course, parents were taught about positive reinforcement for non-depressed activities and positive changes in their children. By the end of the treatment, group 1 had a 43% reduction in depression, group 2 showed a 47% reduction, whilst the control group showed only 5%. All follow up interviews showed depression rates continued to drop over time, suggesting that CBT is valuable in reducing depression in the short and long term, and that positive reinforcement training for parents is also significant.

The cognitive approach to treating depression

The cognitive approach assumes that it is necessary to recognise the importance of internal mental processes such as thought and perception in determining behaviour. In terms of depression, this approach attempts to identify cognitive distortions through therapy, and to challenge them.

One common type of cognitive therapy used to treat depression is Rational Emotive therapy (RET). It was devised by Albert Ellis and aims to target the irrational beliefs that cause depression. It focuses on depressed people's tendency to think catastrophically (worst case scenario) and then challenging the irrational assumptions underlying this tendency. His model is often referred to as the ABC model:

A: Activation (event which triggers depressive thought/depression)

B: belief (main target of therapy; irrational thought/assumption)

C: consequence (what happens as a result; depression)

Study: Beck et al (1978) is one study which looked at cognitive therapies such as RET, comparing their effectiveness to drug therapy. 44 patients diagnosed with depression undergoing therapy (either drug or cognitive) for 12 weeks were monitored. Whilst both groups showed marked improvements, self-report measures and observations made by psychologists suggested that cognitive therapy was substantially more effective in reducing depression and also seemed to be linked to greater adherence (shown by less attrition in the cognitive group).

Similarities:

Both the behavioural and cognitive approaches use face-to-face therapy and recognise the importance of interaction and cognitive elements in treating depression.

None of the approaches are instantaneous; they require a course across several weeks to be effective. 

Differences:

Drug therapy doesn't require much patient-client interaction, nor does it require much effort on the part of the client - this might be more appropriate as lack of energy or concentration is often part of depression. The other two require more effort.

The behavioural approach is the most holistic as it includes both a cognitive and behavioural element, and aims to treat both the depressed person and change their social environment by changing their parents' behaviour. The other two are quite reductionist as they believe depression is simply dispositional in terms of cognition or biology.