Bipolar disorder affects more than 5 million adults in America per year and is categorized in the Diagnostic and Statistical Manual of Mental Disorders as a mood disorder. A person experiencing the symptoms associated with bipolar disorder might exhibit a range of emotions from overly excited and joyful to extreme sadness and depression. In addition to the mood changes there are behavior changes characteristic of this disorder. In the most severe forms, this disorder can be disabling yet there is no specific cause alone for those who are afflicted with this illness.
Biological Causes
Bipolar disorder is caused by physical changes to the brain. A loss in gray matter (which is like a transporter of important information or cells) is a main culprit. This loss contributes to the poor judgment and impulsive behaviors that are commonly associated with a manic episode of bipolar disorder. In regard to the emotional ups and downs the frontal area of the brain has been shown to also have a significant reduction of gray matter, which causes a lack in neuronal or nerve cell connections that are necessary for regulating the emotions.
Neurotransmitters
Neurotransmitters are a communication system relaying information from the brain to the body about how to feel, what to do, memory, thought, hunger, sleep and essential daily functioning. Common neurotransmitters are serotonin, which stabilizes mood; dopamine, which helps with maintaining focus and feelings; epinephrine and norepinephrine, which affect fear, excitement and stress; and GABA, which is a calming chemical. In a person with bipolar disorder the neurotransmitters are imbalanced, causing symptoms of extreme depression, extreme elation, high stress and lack of ability to relax. Neurotransmitters become imbalanced naturally or can be influenced by external stressors such as traumatic environment, substance addiction or significant loss.
Environmental Causes
Stressful environments can lead to changes in the chemical balance of the brain. A stressful environment might include physical and sexual abuse, being a witness to repeated abuse, significant losses of loved ones, caregiver neglect or early onset of drug and alcohol abuse. These external factors can lead to an imbalance of the stress-balancing chemicals typically present in the brain. For instance a person who is overly stressed due to physical abuse can produce increased levels of a chemical in the body called cortisol. When this chemical is too high for too long it can lead to another imbalance of related chemicals further influencing an internal chemical change that triggers bipolar illness. Family occurrence is also a risk factor and genetics have been shown to also play a role in the disorder. Ongoing research continues to explore how environment and genetics contribute to onset of bipolar disorder.
