Bipolar disorder is found in disproportionate numbers in people with creative talent such as artists, musicians, authors, performers, poets, and scientists, and some credit the condition for their creativity. Many famous historical figures gifted with creative talents commonly are believed to have been affected by bipolar disorder, and were "diagnosed" after their deaths based on letters, correspondence, contemporaneous accounts, or other material.
It has been speculated that the mechanisms which cause the disorder may also spur creativity.
Kay Redfield Jamison, who herself has bipolar disorder and is considered a leading expert on the disease, has written several books that explore this idea, including Touched with Fire. Research indicates that while mania may contribute to creativity, hypomanic phases experienced in bipolar I, II, and in cyclothymia appear to have the greatest contribution in creativity). This is perhaps due to the distress and impairment associated with full-blown mania, which may be preceded by symptoms of hypomania (i.e. increased energy, confidence, activity), but soon spirals into a state much too debilitating to allow creative endeavor.
Hypomanic phases of the illness allow for heightened concentration on activities, and the manic phases allow for around-the-clock work with minimal need for sleep.
Another theory is that the rapid thinking associated with mania generates a higher volume of ideas, and as well associations drawn between a wide range of seemingly unrelated information.
The increased energy also allows for greater volume of production.