Biological Explanations of Schizophrenia
Describe and evaluate biological explanations of schizophrenia (24 marks)
Schizophrenia is a psychotic disorder characterized by distorted thinking, impaired emotional responses, poor interpersonal skills and a distortion of reality. It is the most common of psychotic disorders that, in most countries around the world, affects around 1 per cent of the population. In terms of explanations for the disorder, two central types of explanations arise – psychological explanations and biological explanations. Whereas psychological explanations tend to focus on cognitive, emotional and environmental factors that may cause the disorder, biological explanations tend to focus on genetic, biochemical and neuro-anatomical factors as the cause of the disorder.
One biological explanation of schizophrenia is ‘the genetic hypothesis’. Schizophrenia appears to run in families, and Gottesman (1991) has shown through a series of controlled genetic correlational studies that the likelihood of an individual developing schizophrenia is proportional to the amount of genes they share with somebody affected by schizophrenia. For example, children with two schizophrenic parents have a concordance rate of 46 per cent, monozygotic (MZ) twins have a concordance rate of 48 per cent, and dizygotic (DZ) twins have a concordance rate of 17 per cent. However, from these studies it has also been made clear that genetic factors cannot be the only explanation for schizophrenia. Although genetic studies support the argument for a genetic basis for the disorder, they have also shown that even when the relative is genetically identical – like monozygotic twins – the chance of developing schizophrenia is below 50 per cent. This implies therefore, that heredity factors are not the primary cause of schizophrenia, other factors are clearly involved. In addition to this, many researchers have suggested that the reason that schizophrenia appears to run in families could be due to common rearing patterns and
Schizophrenia is a psychotic disorder characterized by distorted thinking, impaired emotional responses, poor interpersonal skills and a distortion of reality. It is the most common of psychotic disorders that, in most countries around the world, affects around 1 per cent of the population. In terms of explanations for the disorder, two central types of explanations arise – psychological explanations and biological explanations. Whereas psychological explanations tend to focus on cognitive, emotional and environmental factors that may cause the disorder, biological explanations tend to focus on genetic, biochemical and neuro-anatomical factors as the cause of the disorder.
One biological explanation of schizophrenia is ‘the genetic hypothesis’. Schizophrenia appears to run in families, and Gottesman (1991) has shown through a series of controlled genetic correlational studies that the likelihood of an individual developing schizophrenia is proportional to the amount of genes they share with somebody affected by schizophrenia. For example, children with two schizophrenic parents have a concordance rate of 46 per cent, monozygotic (MZ) twins have a concordance rate of 48 per cent, and dizygotic (DZ) twins have a concordance rate of 17 per cent. However, from these studies it has also been made clear that genetic factors cannot be the only explanation for schizophrenia. Although genetic studies support the argument for a genetic basis for the disorder, they have also shown that even when the relative is genetically identical – like monozygotic twins – the chance of developing schizophrenia is below 50 per cent. This implies therefore, that heredity factors are not the primary cause of schizophrenia, other factors are clearly involved. In addition to this, many researchers have suggested that the reason that schizophrenia appears to run in families could be due to common rearing patterns and