b. Genetic predispositions
depression is triggered by major life events like loss of reference or a loved one. However, some forms of genes alter the chances of developing the disease is genetic predisposition.
For example, people whose relatives have suffered from depression are 15 % Risk of developing such a while for people whose relatives are not depressed risks are only 2-3%. In addition, children born to parents with a history of depression but adopted by parents who do not suffer from the disease may still make a depression in 15% of cases. So identical twins with exactly the same genes, the probabilities for the twins to live a depression if the other has experienced a rise of 70%.
Yet research in this area are still ongoing and there are only hypothetical.
Thus the mutation gene involved in the transport of serotonin increases the risk of depression. Indeed there are two forms of the gene encoding serotonin: a long form (5 - HTT ) and short allele (5 - HTTLPR ). It was shown that carriers of the short form of the gene most frequently suffer from depression. More in individuals carrying the allele short, subject to anxiety-producing situations the activities of the amygdala and * the cingulum * are disconnected. Instead, their activities are correlated in carriers of the long version. The amygdala, the center of emotions and primitive area of the brain, generate a feeling of anxiety in response to external stimuli, while the cingulum , outer area of the brain, frontotemporal *, would temper this feeling by controlling the activity of the amygdala. The lack of moderation of the amygdala allows runaway activity of the latter, and therefore arouses feelings of fear uncontrolled sources in the long depression. There is no gene for depression or other psychiatric illness. They convey vulnerability to depression.
0 comments:
Post a Comment