The mere fact that, in some persons, vomiting, hiccoughs, micturition, etc.
"Essay on the Creative Imagination"
Th. Ribot
At Stephen's suggestion, at Bloom's instigation both, first Stephen, then Bloom, in penumbra urinated, their sides contiguous, their organs of micturition reciprocally rendered invisible by manual circumposition, their gazes, first Bloom's, then Stephen's, elevated to the projected luminous and semiluminous shadow.
"Ulysses"
James Joyce
As the reflex arc is intact there may be involuntary and unconscious micturition whenever the bladder fills.
"Manual of Surgery Volume Second: Extremities--Head--Neck. Sixth Edition."
Alexander Miles Alexis Thomson