What causes bipolar disorder?

Despite extensive research, the exact cause of Bipolar Disorder has yet to be determined. Scientists do agree, however, that there is no single cause for Bipolar Disorder. Several studies reveal a number of factors working together to produce Bipolar Disorder, including inherited genetic factors and brain structure. Scientists also believe that certain stressful environmental factors may trigger the first episode of mania or depression.

Genetic Disposition

Bipolar Disorder typically runs in families. This has led researchers to examine the genetic composition of those with Bipolar Disorder to determine which genes may cause bipolar depression and mania. Studies have concluded that although genetics play a role in the likelihood of developing symptoms of Bipolar Disorder, there is no exclusive link to genetics. Studies of identical twins, who share identical genes, reveal that if one twin has Bipolar Disorder, that does not necessarily mean the other twin has it. If Bipolar Disorder were exclusively genetic, both twins would always have the disorder. Research has shown, however, that Bipolar Disorder tends to run in families, and those with family members diagnosed with the disorder are more likely to develop the disorder.

Additional studies indicate that Bipolar Disorder does not occur from a solitary gene. It appears that many different genes act together in conjunction with a person’s environment to create symptoms of Bipolar Disorder.

Differences in Brain Structure

Scientists have developed new methods of studying the brain structures of those suffering from Bipolar Disorder. Magnetic resonance imaging (MRI), positron emission tomography (PET), and functional magnetic resonance imaging (fMRI), are non-invasive techniques that allow doctors to study the living brain at work, without the need for surgery. These tests have revealed that those suffering from Bipolar Disorder may have slightly different brain structures than those not afflicted. These differences are being closely researched in order to gain a greater understanding of the cause and potential treatment options for those with Bipolar Disorder.

Environmental Factors

There is evidence that Bipolar Disorder may be triggered by environmental stresses. Stressful life events such as the death of a loved one, the loss of a job, or the birth of a new baby have the potential to bring about the onset on Bipolar Disorder. There is evidence that those with Bipolar Disorder may have difficulty coping with outside stressors. Once the disorder is triggered, it seems to manifest in unpredictable ways. After a stressful event, a psychological and physiological cycle of mania and depression develops in those with Bipolar Disorder.