Essay - Bipolar Disorder: a Biological Overview Bipolar Disorder is One of...

bipolar disorder: A Biological Overview

***** ***** is one of the most complex and difficult to treat ***** the major mood disorders. There are several different forms of the illness. Some bipolar I disorder patients exhibit alternating episodes of mania ***** depression, while other sufferers show less florid periods of *****, a state called hypomania that alternates with depression. These sufferers ***** said ***** ***** a less severe form ***** the illness, ***** bipolar II disorder ("Bipolar *****," 2007, NIH). Susie, given her delusions during periods of mania, seems to exhibit ***** I features in her manifestation of the disorder. She ********** full-blown mania, and exhibits the manic symp*****ms of elevated mood, over-activity sleeplessness, overconfidence, paranoia, and impaired judgment. Mania is what distinguishes bipolarity from the mood ***** ***** depression. "A single ***** episode is sufficient for the diagnosis of bipolar illness" (Belmaker 2004).

Regarding its biological basis, in both forms ***** bipolar disorder, the evidence regarding the influence of neurotransmitters is both frustrating and conclusive. It ***** ***** in the sense *****, like all ***** the major mood **********, there is a very clear l*****k between neurotransmitters in the brain ex*****ting in a st*****te of imbalance and ***** development ***** the disorder. Exactly how this imbalance functions remains mysterious in this illness. Some studies have suggested that a low or high level of a specific neurotransmitter such as serotonin or dopamine may be ***** cause. Serotonin is the 'feel good' chemical *****ten in a state of deficit ***** depressed patients, and anti-depressant medications inhibit the ability of ***** body to soak up *****, and thus increase the levels ***** ***** *****. Dopamine is the 'thrill seeking' chemical often present in too great an abundance in the bra*****s of schizophrenics. Yet ***** studies of bipolar patients "indicate that an imbalance of these substances is the problem, i.e., that a specific level of a neurotransmitter ***** not as important as its amount in relation to the other ***** (Read 2007:1).

Despite ***** physical component, bipolar disorder is ***** like *****heriting blue or brown eyes. "Linkage studies ***** identified markers, which have *****en replicated in more than one study, particularly on chromosomes 18 and 22. However, no single locus has been consistently *****, ***** the contribution ***** any identified locus appears small. Progress in genomic medicine offers the hope that ***** genes that confer an elevated risk of ***** illness will be found" (Belmaker *****). In other words, it cannot be predicted that a child will definitely h*****ve the disorder, based on a genetic test, but ***** clearly influence the tendency ***** develop the disorder, particularly under periods ***** intense stress. Families of persons with bipolar disorder also seem more likely to have a mood disorder than the relatives of those who do not have bipolar disorder, as in ***** c*****e ***** Susie. "Approximately 50 percent of patients with ***** ***** have a family history of the disorder" (***** 2004).

Note that this tendency is ***** only specific to bipolarity, ***** to