An alternative explanation is family models. Recent research has centred on the concept of expressed emotion (EE). Families that are hostile, show criticism and are over concerned place vulnerability to schizophrenia because they class as a high expressed emotion family. This was originally based on work by Brown which showed that patients with schizophrenia were more likely to relapse if they retuned homes characterised by high levels of expressed emotion than to homes characterised by low levels of expressed emotion (Low EE).
Research by Brown was further supported by Tarrier which consistently showed that there is a strong relationship between relapse and living with high EE relatives. Showing that high EE is a strong predictor of the disorder.
Further support by Vaughn and Leff showed that there was a 51% relapse in high EE but 13% in low EE. In addition to this, there was a 92% relapse in high EE without medication which further proves that the environment determines the severity of the disorder.
However the studies of EE have many methodological issues of assessing it. Firstly, the way of assessing whether a person is in a high or low EE family is through interviews. Using interviews could arise social desirability bias as they family will act different in order to ‘look better’. Also researcher bias may occur due to the researcher only wanting to find one set of answers and not recording all the true findings. Lastly, studies are correlational which means we cannot infer cause and effect and therefore may reflect the consequences of living with someone with schizophrenia rather than having any significance. All in which undermine the internal validity of the findings which means we cannot fully rely upon these findings.
Also Kavanagh found that high EE patterns have also been found in families of patients with other disorders such as depression and eating disorders. Therefore, it isn’t a defining characteristic of families with a schizophrenic member.
In spite of these limitations, it seems clear that the family environment has a role in the onset, and the course of schizophrenia. Several prospective studies have been conducted that have found high-risk children who go on to develop schizophrenia, in contrast to those who do not, are more likely to come from families characterised by negative relationships. For example, the Israeli high risk study found that, those who were at high risk but had good parenting from a parent with schizophrenia didn’t go on to develop the disorder compared to those with bad parenting did. It is thought that bad parenting alone doesn’t cause the disorder but rather the vulnerability in certain individual with environment stressors.
Lastly, this approach only focuses on the nurture of the debate by only considering the environment and not biology.
Therefore, an alternative explanation that acknowledges memory through the cognitive models. This sees faulty thoughts as the cause of schizophrenic symptoms such as disordered thoughts and hallucinations. Helmsley proposed a breakdown between stored memories and new incoming information occurring. Stored information is used to create schemas allowing people to interpret the world and situations. However, schizophrenics may not have these schemas activated. This may be because of the breakdown in cognitive processes which then causes an overload of sensory information as schizophrenics struggle to intensity what to attend to or ignore. Which results in delusional thoughts which are then interpreted as originating externally rather than from memory.
Becker et al found that schizophrenics struggled to integrate moment-to-moment sensory input with stored memories supporting Helmsley’s cognitive model.
Cognitive explanations appears to provide a reasonable explanation for positive symptoms but do not explain negative symptoms.
However, it’s not clear whether the cognitive dysfunction is a cause or effect of the disorder. Therefore, cognitive models may only be descriptive; explaining the symptoms of schizophrenia rather than explaining them.
Similarly, many brain-damaged patients have problems with attention or with the relationship between memory and perception. Despite having these cognitive deficits, they fail to develop the symptoms of schizophrenia and so this challenges the cognitive explanations.
Overall, the psychological explanations have implications for treatments. For instance, CBT is an effective treatment for schizophrenia focussed through the cognitive theories. If the treatment is effective then the theory must be correct to some extent.
Lastly, the psychodynamic and family models favour the nurture debate compared to cognitive models which favours nature. Due to favouring one side, the approaches become reductionistic as it either fails to consider the environment or biology. Therefore, a more holistic approach should be considered in order to be completely valuable.