Tuesday, October 29, 2019

Effects of race on the perception of Guilt Essay Example for Free

Effects of race on the perception of Guilt Essay Affective mood disorders are mental disorders characterised by disturbances in mood and emotional states, unlike Schizophrenia, the most severe of mental disorders, which is distinguished by problems with thought processes. These affective mood disorders can include variations such as Bipolar disorders where the patient experiences two extreme states; mania accompanied with depression and Unipolar disorders where only the depressive state is present. There have been many suggestions as to the cause of these disorders. It has long been thought that there are two types of depression: reactive and endogenous. Reactive depression follows the psychodynamic view that depression relates to life events such as loss of a loved one and endogenous depression mirrors the cognitive approach where the individual attributes failures internally thus bringing on depression. However the DSM-IV only lists two sub-types of depression, which are reliant upon the length that the patient has suffered for. These are major depressive disorder and dysthymic disorder. Biochemical explanations are mainly associated with unipolar depression and were developed in the 1950s with the introduction of Tricyclic drugs, which were discovered to help those with depressive symptoms. It has been suggested that chemical imbalances in the brain cause these depressive symptoms. Neurotransmitters such as serotonin, norepinephrine and dopamine are believed to be of a higher level in patients with no signs of depression compared to lower levels in those with depression (Schildkraut, Green and Mooney, 1985, in Gleitman et al, 1999) However, it is only possible to investigate this by measuring the by-products of the metabolising neurotransmitters. Although it has been found that patients with depression have lower levels of these by-products, Cooper (1988, in Cardwell et al, 2000) carried out post-mortems on patients who had suffered from depression and found that there was no abnormality in the chemicals of the brain. Medications used to treat depression can be used in support of the biochemical hypothesis as drugs such as Lithium and Tricyclic antidepressants increase the levels of norepinephrine and serotonin in the brain implying that it was the shortage of these chemicals that was causing the depression. Rosenzwig, Leiman and Breedloves (1996, in Gleitman et al, 1999) experiment also supports this view as it was discovered that lowering the levels of the neurotransmitters works in reverse and can cause depression. However, these anti-depressant drugs cause an immediate increase in the levels of norepinephrine, following the biochemical hypothesis once the norepinephrine level is increased depressive symptoms should disappear. In fact it takes 2-3 weeks after first taking the drugs for an effect to be seen, yet within a couple of days after taking the drugs the norepinephrine levels have returned to their previous level. This hinders the biochemical hypothesis and suggests that it may not purely be a chemical imbalance that causes depression. Patients who suffer with bipolar depression also have low levels of norepinephrine during a depressed phase, returning to a higher level when in a manic stage, (Muscettola et al, 1984,in Gleitman et al, 1999) the switch between the manic and depressive phases occur very quickly and without external influences, indicating that it is in fact a biological rather than psychological reason that causes this switch to take place. Another strand to the biological approach is the question; does depression run in families? The biological explanation supports this suggestion. There have been numerous twin studies comparing concordance rates of MZ (identical twins) with DZ (non-identical) twins, all giving evidence for some genetic transmission. Evidence for a genetic link concerning bipolar disorders comes from a study carried out by Hodgkinson, Mullan and Gurling, (1990, in Gleitman et al, 1999); they discovered that patients who had bipolar disorder also had an enzyme deficiency accompanied by a type of colour blindness. All of these irregularities are caused by a defect on the X-chromosome. This indicates that the genetic cause of bipolar disorder also lies with the x-chromosome and may explain to a certain degree why it has been found that more women than men suffer from bipolar depression. However it is important to note that women, no matter what culture have a different social support structure to men, allowing them to talk more about their problems. Therefore it may simply be the case that more women report their problems than men, who keep their feelings of depression to themselves. This difference also occurs with unipolar depression and can be accounted for by the vast amounts of hormonal changes women endure through menstruation, child carrying and the menopause. McGuffin et al (1996) compared 109 pairs of twins and found a rate of 46 per cent concordance in MZ twins to that of 20 per cent in DZ twins; this study shows a genetic link for depression but that it is not the only factor. If depression were only caused by genetics then the concordance rates would be 100 per cent for MZ twins and 50 per cent for DZ twins, suggesting that other factors play an important role. This genetic link may be due to environmental factors as the patients are likely to live in a shared environment. This suggests that the concordance rates occur not because depression is hereditary but because it can be learnt. This however could also work in reverse; a relative may not suffer from depression because they have experienced depression and have learnt ways to cope with their feelings and experiences. This can also be illustrated by Siever, Davis, and Gorman, (1991, in Gleitman et al, 1999) who carried out twin studies that showed identical twins were four times more likely to both suffer from a mood disorder than non-identical twins. Identical twins have a closer shared environment than non-identical twins, which may account for the higher concordance rate amongst identical twins.

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