The driving compulsion to write; the overwhelming urge to write.
Affliction which causes the sufferer to transcribe their thoughts uncontrollably, presumably caused by temporal lobe epilepsy, or a right cerebral stroke.
Temporal lobe epilepsy is associated with hypergraphia. This association has been known at least as early as 1974 (Waxman SG, Geschwind N. Hypergraphia in temporal lobe epilepsy. Neurology. 1974;24:629-36). A number of prolific writer may have had temporal lobe epilepsy, including Byron, Dante, Dostoevsky, Molière, Petrarch, Poe, and Tennyson.
Hypergraphia has also been called the midnight disease.