Certified Ophthalmic Medical Technologist (COMT) Practice Exam

What name is given to the returning motor pathway for the light reflex that affects pupillary response?

1. Afferent pathway

2. Efferent pathway

3. Convergence pathway

4. Accommodation pathway

The correct answer is: Efferent pathway

The returning motor pathway for the light reflex that affects pupillary response is known as the efferent pathway. This pathway is essential for facilitating the contraction of the iris sphincter muscle, which results in pupillary constriction in response to light. When light hits the retina, the sensory information is transmitted along the afferent pathway to the brain, where the signal is processed. Subsequently, the efferent pathway carries the motor commands from the brain back to the eye, prompting the pupil to constrict. The efferent pathway primarily involves the oculomotor nerve (cranial nerve III), which innervates the muscles responsible for changing the size of the pupil. This action is crucial for protecting the retina from excessive light exposure and optimizing vision. Understanding this distinction between afferent and efferent pathways is critical for comprehending how the nervous system coordinates eye responses to various stimuli.