Grand mal seizure in a snake

YouTube link.

The snake is a Black Racer, photographed in Naples, Florida by the sister of reader Ron Rizzo, who forwarded it to us to share. During the first half of this brief video the snake exhibits only some purposeless writhing on the side of a road.  Then it launches into full-blown grand mal seizure activity, which according to the photographer was a pre-terminal event.
Any animal with a brain is susceptible to motor seizures, which are a manifestation of uncontrolled electrical activity in the neurons.  If I had to guess at an etiology, the roadside occurrence would suggest to me that the snake had previously incurred head trauma from a passing vehicle, which eventually led to cerebral edema or intracranial bleeding.  Alternatively it may have encountered a poison or a neurotoxic venom.  In any case, it's a interesting activity to observe.