Depression And Anxiety Disorders: A Literature Review
becomes increasingly difficult. It also incldes feeling restlessness, easily fatigued, concentration diminished, irritable, muscle tension and sleep disturbance. (Diagnostic and Statistical Manual of Mental Disorders, 2000).
Most people that experience negative life events do not always develop depression or anxiety (Brown, Bifulco, & Harris, 1987) for this reason there is strong evidence to suggest that some may be susceptible. Studies have shown biological roots, Caspi et al, 20003 discovered a polymorphism in the Serotonin transporter region (5-HTT). There are several polymorphisms in this gene, (Peterson et al., 2012), however, the most investigated candidate gene is the 5-HTTLPR. The gene consists of a long “L,” and “S” allele. Evidence suggests that the L allele has a higher serotonin uptake capacity than the S allele, and appears in variations of LL, LS or SS. Individual that carry the S allele have been found to show lower levels of serotonin thus experiencing higher risk of stress sensitivity. These results have been found in studies which have replicated it, Caspi, Hariri, Holmes, Uher, & Moffitt, (2010); Uher & McGuffin, (2008), Aslund et al., (2009); Benjet, Thompson, & Gotlib, (2010); Chipman et al., (2007); Eley et al., (2004); Uddin et al., (2010).
When negative events happen combined with the genetic disposition, the body ability to cope with elicited stress alters the functions of the autonomic nerves that synchronize to the Central Nervous…