Indirect Pupillary Light Reflex. While there are other reasons for variation in pupillary dilation and constriction such as arousal leading to changes in the balance of the sympathetic and parasympathetic nervous systems here we will focus on its relation to light exposure. The pupillary light reflex or photopupillary reflex is a reflex that controls the diameter of the pupil in response to the intensity of light that falls on the retinal ganglion cells of the retina in the back of the eye thereby assisting in adaptation of vision to various levels of lightness darkness.
The consensual plr is the constriction of the pupil in the eye opposite to the eye stimulated with light. The pupillary light reflex or photopupillary reflex is a reflex that controls the diameter of the pupil in response to the intensity of light that falls on the retinal ganglion cells of the retina in the back of the eye thereby assisting in adaptation of vision to various levels of lightness darkness. Argyll robertson ar pupil may also be irregular usually bilateral see below.
The direct plr present in virtually all vertebrates is the constriction of the pupil in the same eye as that stimulated with light.
The pupillary light reflex plr is the constriction of the pupil that is elicited by an increase in illumination of the retina. The room lights should be dim barely allowing you to see the iris and pupil. Observe the pupil size and shape at rest looking for anisocoria one pupil larger than the other observe the direct response constriction of the illuminated pupil. Normal pupil functions.
