Bipolar Disorder Research Starter
The DSM-5 divides bipolar disorder into bipolar I disorder, bipolar II disorder, and cyclothymic disorder.
There is a genetic link to bipolar disorder, and individuals who have at least one parent with the disorder are significantly more likely to develop it themselves. An increased level of calcium ions is found in the blood of patients with bipolar disorder. There is also a lowered blood flow in the brain, as well as slower overall metabolism. Some research suggests that bipolar disorder may be caused by disturbed circadian rhythms and related to disturbances in melatonin secretion. Treatment options include psychotherapy and medication. Mood stabilizers, such as lithium and divalproex sodium, are the most commonly used medications.
Major Depressive Disorder Research Starter
Major depressive disorder, often known simply as depression, involves disturbances in mood, concentration, sleep, activity, appetite, and social behavior. A major depressive episode may develop gradually or appear quite suddenly, without any relation to environmental factors. The symptoms of major depressive disorder will vary among individuals, but there are some common symptoms. People with major depressive disorder may have difficulty falling asleep, sleep restlessly or excessively, and wake up without feeling rested. Even minor decisions may seem impossible to make. A loss of energy is manifested in slower mental processing, an inability to perform normal daily routines, and slowed reaction time. They ruminate about failures and feel guilty and helpless. They see no hope for improvement and may be thinking of death and suicide. In adolescents, depression may be manifested in acting out, anger, aggressiveness, delinquency, drug abuse, poor performance in school, or running away. Depression is a primary risk factor in suicide, one of the leading causes of death among young people in the United States.
There is probably no single cause of major depressive disorder, although it is primarily a disorder of the brain. A chemical dysfunction and genetics are thought to be part of the cause. Neural circuits, which regulate mood, thinking, sleep, appetite, and behavior, do not function normally. Neurotransmitters are out of balance. One neurotransmitter implicated in depression is serotonin. In many patients with the disorder, the hormonal system that regulates the body’s response to stress is overactive. Stress, alcohol or drug abuse, medication, or outlook on life may trigger depressive episodes.
In most cases, medication, psychotherapy, or both are the treatment of choice. Treatment depends on the severity and pattern of the symptoms. With treatment, the majority of people with major depressive disorder return to normal functioning.
