Mydriasis iris sphincter, composed of circularly arranged muscle fibers, and the iris dilator, composed of radially arranged muscle fibers. The sphincter is innervated by (signaled by nerves of) the parasympathetic nervous system, and the dilator by the sympathetic nervous system. Sympathetic stimulation of the adrenergic receptors causes the contraction of the radial muscle and subsequent dilation of the pupil. Conversely, parasympathetic stimulation causes contraction of the circular muscle and constriction of the pupil. The mechanism of mydriasis depends on the agent being used. It usually involves either a disruption of the parasympathetic nerve supply to the eye (which normally constricts the
This Is What You Want... This Is What You Get were not re-recorded for "This Is What You Want...This Is What You Get" (although a remixed version of "Blue Water" was included as the B-side on the "This Is Not a Love Song" 12" single). Songs on "This Is What You Want...This Is What You Get" which did not appear in any form on "Commercial Zone" are "Tie Me to the Length of That", "The Pardon" and "1981", and are the only songs on the album which do not credit Keith Levene as a co-writer. PiL was supposed to score the soundtrack for the 1983 suspense film "Copkiller", starring Harvey