But while lack of sleep does diminish basic functions like reflexes and recall, paradoxically, the brink of sleep can be salutary to creativity: In that liminal space between restlessness and rest, the mind's organizing principles begin to fray with the fatigue of the day's conscious labors and unbidden thoughts begin to emerge from the recesses of the unconscious, begin to collide with one another in the seething cauldron of the insomniac's angst, begin to form the unexpected combinations we call originality.