Iris sphincter muscle Iris sphincter muscle The iris sphincter muscle (pupillary sphincter, pupillary constrictor, circular muscle of iris, circular fibers) is a muscle in the part of the eye called the iris. It encircles the pupil of the iris, appropriate to its function as a constrictor of the pupil. It is found in vertebrates and some cephalopods. Initially, all the myocytes are of the smooth muscle type but, later in life, most cells are of the striated muscle type. Its dimensions are about 0.75 mm wide by 0.15 mm thick. In humans, it functions to constrict the pupil in bright light (pupillary light
Look at What the Light Did Now Look at What the Light Did Now Look at What the Light Did Now is a documentary/live album DVD/CD by Canadian indie pop artist Feist, first released in December 2010. The DVD comprises an 80-minute documentary directed by Anthony Seck, five music videos from 2007 album The Reminder, and a number of live performances recorded between 2007 and 2009, including covers of songs by artists such as Little River Band and Ron Sexsmith. The set's accompanying CD features live tracks and solo piano takes of tracks from "The Reminder", along with live covers of songs by artists such as The