Models of Abnormality

Medical and Biological Models 

Belief that mental disorders are caused by biological processes:

• Biochemical – existence and avalilability of certain neurotransmitters. E.g. An excess of dopamine is linked with schizophrenia.
• Genes – existence of certain genes. This explanation uses twin/adoption studies and concordance rates to be reliable. Kendler et al found that relatives of schizophrenics are 18 times more likely to develop a mental illness.

Doctors believe that mental illnesses are like any other illness based on physical conditions, therefore it can be diagnosed and treated in the same way. The focus is on the physiological nature of the problem rather than behavioural or emotional factors.

Strengths:

1. Humane – patients are not blamed for the abnormality, which can also help in reducing their anxiety or symptoms in certain situations.
2. Objective – evidence is drawn from brain scans and postmortems, which makes the theory more reliable as scientific techniques are used and these are standardised.
3. Effective treatments – drugs are known to be useful with most abnormalities such as schizophrenia.

Weaknesses:

1. Reductionist – the theory does not take into account other factors such as emotions or behaviour, which makes less valid.
2. The theory treats the symptoms, not the cause of the mental illness, meaning that the abnormal behaviour may show up again later on in life.
3. Cause and effect – the biological and medical models are mostly based on correlations, meaning that it cannot be determined what causes the illness and what the effects are.
4. Treatment – some research has shown that patients receiving placebod fared as well as those receiving drugs.

Behavioural Model 

Belief that dysfunctional behaviour is learned the same way as any other behaviour:

• Classical conditioning – learning through association (Little Albert learning a white rat phobia)
• Operant conditioning – learning through reinforcement (Mineka et al showed adult monkeys being scared of snakes to baby monkeys)
• Social learning – learning through observation. (Bandura’s theory)

Behaviourists believe that there is not biology or emotions involved in abnormality, but the focus is on the observable behaviour. 

Strengths:

1. Focus on current behaviour, which makes the model more reliable and high in ecological validity.
2. Experiments – the model carries out many laboratory experiments, which are controllable and testable, meaning that it has high reliability.

Weaknesses:

1. The theory focuses on the symptoms, not the cause of the mental illness, meaning that the abnormal behaviour may show up again later on in life.
2. Reductionist – the theory does not take into account other factors such as emotions or biology, which makes less valid.
3. Experiments – laboratory experiments do not have high ecological validity because participants are not experiencing their natural environment.

Psychodynamic Model 

Belief that abnormal behaviour is developed through:

• Unhealthy relationships with parents in childhood.
• Traumatic experiences that may disrupt our relationships.
• Early negative experiences that are stored in our unconscious mind.
• Any unmet childhood needs and unsatisfied biological instincts.

Psycho dynamic psychologists believe that if children come fixated with one of the 5 stages of psycho sexual development (Oral, Anal, Phallic, Latency, Genital), it can lead to mental illness in adulthood.

Strengths:

1. Case studies – the model uses case studies for research, which collect in-dept data and focus on the individual; therefore, the theory can be said to take into account individual differences and is valid.
2. Influential – the model is one of the most established because of the large amount research carried on it.

Weaknesses:

1. Not testable – the ‘unconscious’ is not real and does not have any scientific evidence for it, therefore the reliability of the theory is quite low.
2. Reductionist – the model does not take into account other factors such as emotions,biology or behaviours,  which makes less valid.
3. Gender bias – the model has mainly been tested and focused on men, meaning that the research cannot be generalised to women.

Cognitive Model 

Belief that abnormal behaviour is caused by:

• Faulty information processing and thought processes, as a result of early life experiences.
• Purely cognitive factors, such as memory systems and irrational beliefs.

Cognitive psychologists believe that mental events result in dysfunctional behaviour because humans interpret the environment before reacting to it; therefore, abnormal behaviour is the result of our cognitive interpretations.

Strengths:

1. Irrational beliefs may be realistic because they are the definition of phobias in the DSM.
2. Research – Gustafon (1992) found that maladaptive thinking was linked to anxiety.

Weaknesses:

1. Cause and effect – the cognitive model is mostly based on correlations, meaning that it cannot be determined what causes the illness and what the effects are.
2. The model holds the individual responsible, which might deteriorate their mental illness and make it worse.