Dilator Pupillae
Eye
Dilates the pupil during sympathetic arousal — your pupils widen when you're scared, excited, or attracted to someone. Controlled by fight-or-flight.
Function
Pupil dilation (mydriasis)
Origin
Radial smooth muscle of iris
Insertion
Fibers radiate from iris root to pupillary margin
Innervation
Sympathetic fibers from superior cervical ganglion