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Postganglionic fibers go to the pupillary constrictor muscles in the iris. \(Note: the ciliary muscles also receive output from the EW nucleus. During accommodation for near vision the ciliary muscles contract, relaxing the tension of the zonule fibers and allowing the lens to round up, thus increasing its focusing power\). The insert at the right is an MRI axial \(horizontal\) scan at about the level of the drawing.")) 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