Hence, evaluating schizophrenia ignoring the environmental factors can be seen as reductionist and deterministic. Moreover, there is some confusion as to whether one or many genes are responsible for predisposing a person to schizophrenia. However, as the genetic approach adopts technological explanations such as using brain scan or genome, its explanation can be seen as more scientific than other approaches such as the cognitive explanation which focuses on the thinking processes which are quite subjective and difficult to be treated. The dopamine hypothesis can be supported by evidence.
Amphetamines increase the amount of dopamine and large doses of amphetamine given to people with no history of psychological disorder often produce behaviour which is very similar to paranoid schizophrenia (Sz) whereas small doses given to people already suffering from Sz tend to worsen their symptoms. There is also further evidence that points to the connection between dopamine and Sz which comes from antipsychotic drugs used to treat the disorder. They work by blocking dopamine receptors, thus preventing dopamine-receiving neurons from firing.
The Essay on Outline and Evaluate One or More Biological Explanations of Schizophrenia
... be entirely discounted. A second biological explanation is the dopamine hypothesis which believes schizophrenia symptoms occur as a result of ... biased way to create a narrative about schizophrenia that subtly prioritises genetic explanations. Also even in rare cases where MZ ... Outline and evaluate one or more biological explanations of schizophrenia. In your evaluation you should refer to research ...
Additionally, L-Dopa, which is used to treat Parkinson’s disease (caused by lack of dopamine), can produce Sz symptoms in individuals with no history of the disorder. However, the evidence is inconclusive since other studies have failed to reveal an excess of dopamine receptors. Further problems with the dopamine hypothesis include the finding that antipsychotic drugs which block dopamine receptors, do not appear to help a significant number of people with Sz. They appear much more effective in cases of Type 1 Sz than in Type 2.
Second, these drugs block dopamine receptors quickly, yet even when they are effective, the symptoms can take weeks or even months to subside. Furthermore, the developments of new types of drugs such as clozapine which are known as antipsychotic drugs block fewer dopamine receptors than traditional anti-psychotics. However, they block many receptors for the neurotransmitter serotonin. They appear particularly effective in reducing the symptoms of Type 2 schizophrenics. Recent research suggests that Sz may result from the interaction of serotonin and dopamine rather than dopamine alone.
As Davison and Neale (1998) suggest, ‘Sz is a disorder with widespread symptoms covering perception, cognition, motor activity and social behaviour. It is unlikely that a single neurotransmitter, such as dopamine, could account for them all. ’ For Structural Brain Abnormalities (innate brain structure), PET scans have shown a tendency towards abnormality low activity in the frontal lobe of the brain in Type 2 Sz, who show mainly negative symptoms (Andreasen et al, 1990).
Those who display mostly positive symptoms-Type 1- tend to have abnormalities of the limbic system and temporal lobes of the brain.
Bogerts (1993) sees this as evidence that there are two distinct types of Sz which are caused by different brain abnormalities. Also, CAT scans have shown that the larger ventricles in the brain of Sz patients than the ones in normal people. Although the enlargement of ventricles may not be a problem, it may indicate that nearby parts of the brain have not developed properly or have atrophied. The evidence to support this idea is that some studies show that Sz tend to have smaller frontal lobes, smaller amounts of cortical grey matter, and a reduced blood flow in their brains (Comer, 1998).
The Report on Types of Family Violenc
Informative Speech Types of Family Violence Introduction Attention material: “Family violence accounted for 11% of all reported and unreported violence between 1998 and 2002. Of these roughly 3.5 million violent crimes committed against family members, 49% were crimes against spouses, 11% were sons and daughters victimized by a parent, and 41% were crimes against other family members.”(Writer ...
The apparent link between Sz and brain abnormalities has led to a search for the cause of those abnormalities. Lastly, the Diathesis Stress Model is supported by an important on-going study in Finland (Tienari et al, 1994).
The researchers found 171 women diagnosed as Sz who had a child that was adopted before the age of 4. The adoptive families were interviewed and given a series of tests. On this basis, they were judged to be ‘healthy’, ‘mildly disturbed’ or ‘severely disturbed’. None of the adopted children raised in ‘healthy’ families developed Sz.
However, 9% raised in ‘mildly disturbed’ families and 11% in ‘severely disturbed’ families developed the disorder. This suggests that a well-adjusted family environment protects children who may be predisposed to Sz, whereas a disturbed family environment may encourage this predisposition to express itself in the disorder. Biological treatments arise from the biological model of disorders which considers mental disorders to be an illness or a disease resulting from underlying biological factors.
Amongst various biological treatments, the main one is drug therapy since most people with Sz take some form of medication. However, with some success of other treatments such as behavioural or cognitive ones, the drug therapy can be seen as becoming out of date. is considerable evidence that drugs such as antipsychotic drugs (reduce the effects of dopamine), atypical drugs (reduce serotonin activity) and phenothiazines can reduce positive symptoms such as hallucinations in many people with Sz.
They produce the maximum benefits within the first 6 months. More recently, atypical drugs have been used, such as clozapine which block serotonin receptors. Some research suggests that these can be more effective than conventional drugs. Kane’s research shows the effectiveness of fluphenazine (a type of phenothiazine) in treating Sz, adding support to the biological theory of dysfunctional behaviour. His conclusion was that patients with one episode of Sz can be successfully treated using fluphenazine (both types) once they were in remission.
