A neurologist reflects on hypergraphia, “the medical term for an overpowering desire to write”:
Evidence that ranges from Nabokov to neurochemistry, Faulkner to functional brain imaging, shows that thinking about excesses and dearths of writing can also clarify normal literary output and the mechanisms of creativity….
Hypergraphia doesn’t guarantee writing skill; its products can range from the simple (for instance, an epileptic patient whose copious journal was endless repetition of the thought “Thank GOD, no seizures” in variously colored ink) to the sublime (the novels of Dostoevsky or Flaubert, also temporal-lobe epileptics). But a compulsive need to write may indirectly make good writing more likely by increasing the time the writer spends practicing. This may be one factor in the very high incidence of manic-depressive writers. Kay Redfield Jamison calculates that poets are up to 40 times more likely than the general population to have had manic episodes….
Most writers with depression do their writing not while depressed, but while on the edge of a mood change, or in a rebound euphoria. Indeed, many writers who carry the diagnosis of depression actually have mild bipolar disorder. This in part explains why writers can have odd combinations of block and hypergraphia simultaneously.
* Establishment-media types may deduct 25 points for gratuitous and probably disingenuous (?) reference to mental illness.