Another type of depression is bipolar disorder, also called manic-depressive illness. Not nearly as prevalent as other forms of depressive disorders, bipolar disorder is characterized by cycling mood changes: severe highs (mania) and lows (depression). Sometimes the mood switches are dramatic and rapid, but most often they are gradual. When in the depressed cycle, an individual can have any or all of the symptoms of a depressive disorder. When in the manic cycle, the individual may be overactive, overtalkative, and have a great deal of energy. Mania often affects thinking, judgment, and social behavior in ways that cause serious problems and embarrassment. For example, the individual in a manic phase may feel elated, full of grand schemes that might range from unwise business decisions to romantic sprees. Mania, left untreated, may worsen to a psychotic state.
SYMPTOMS OF DEPRESSION AND MANIA
Not everyone who is depressed or manic experiences every symptom. Some people experience a few symptoms, some many. Severity of symptoms varies with individuals and also varies over time.
Depression
Persistent sad, anxious, or "empty" mood
Feelings of hopelessness, pessimism
Feelings of guilt, worthlessness, helplessness
Loss of interest or pleasure in hobbies and activities that were once enjoyed, including sex
Decreased energy, fatigue, being "slowed down"
Difficulty concentrating, remembering, making decisions
Insomnia, early-morning awakening, or oversleeping
Appetite and/or weight loss or overeating and weight gain
Thoughts of death or suicide; suicide attempts
Restlessness, irritability
Persistent physical symptoms that do not respond to treatment, such as headaches, digestive disorders, and chronic pain
Mania
Abnormal or excessive elation
Unusual irritability
Decreased need for sleep
Grandiose notions
Increased talking
Racing thoughts
Increased sexual desire
Markedly increased energy
Poor judgment
Inappropriate social behavior
What lepton described is not bipolar disorder, but it sure sounds that "spacey" behavior described in the article. The above definition of bipolar disorder and symptoms was from the National Institute of Mental Health(NIMH). Here's the URL:
http://www.nimh.nih.gov/publicat/depression.cfm#ptdep3