Certified Ophthalmic Technician (COT) Practice Test

The condition that indicates a discrepancy in light information transmitted to the brain from each eye is the afferent pupillary defect. This is a neurological condition where one eye receives less light information than the other, often due to damage to the optic nerve or severe retinal disease. When light is shone in the affected eye, both pupils may dilate instead of constricting, which is known as a Marcus Gunn pupil. This phenomenon occurs because the affected eye's diminished response to light results in a relative afferent pupillary defect compared to the unaffected eye. Other conditions mentioned, such as ophthalmoplegia, involve issues with eye movement rather than the transmission of light information. Convergence insufficiency relates to the ability of the eyes to work together during near tasks, focusing rather than light transmission. Blepharospasm involves involuntary eyelid muscle contractions and does not pertain to the way light information is processed. Hence, afferent pupillary defect is the most relevant diagnosis associated with discrepancies in light information reaching the brain.