Dull reflex to light is a test to check the functional activity of the pupil, divided into direct reflex to light and indirect reflex to light. For direct light reflex, the pupil is usually illuminated directly with a flashlight and its dynamic response is observed. In a normal person, the pupil narrows immediately when the eye is stimulated by light and recovers quickly when the light source is removed. Indirect light reflex means that when light is shone on one eye, the pupil of the other eye immediately narrows, and when the light is removed the pupil expands. When examining indirect light reflexes, one hand should be used to block the light so that the eye is not exposed to direct light reflexes. A dull or absent pupillary light reflex is seen in comatose patients. The afferent fibers of the light reflex travel through the optic nerve and the optic tract, branching out into the internal tract near the lateral geniculate body and reaching the superior colliculus, ending at the nucleus of the anterior parietal area. Intermediate neurons connect the parasympathetic Edinger-Westphal nucleus (EW nucleus), or the parasympathetic nucleus of the autonomic nerve, on both sides. Thus, when one eye is stimulated, the pupil of the other eye also contracts (indirect response to light). The reflex pathway starts again from the EW nucleus, follows the motor nerve to the ciliary ganglion, and the last neuronal tract emanates from the ciliary ganglion cells to the pupillary dilator muscle.