What is the sequence of visual processing?

• A. Light enters, is focused on the retina, converted to neuronal activity, and sent to multiple brain structures.
• B. Light enters the pupil and is immediately interpreted by the frontal cortex.
• C. Photons are processed in the retina and then decoupled into sound signals.
• D. Neuronal activity is generated before any light exposure.

Answer: (A)

Visual processing starts when light enters the eye and is focused on the retina, where photoreceptors (rods and cones) convert light into neural signals. Those signals are then transmitted via retinal ganglion cells into the optic nerve and project to multiple brain structures, including the lateral geniculate nucleus of the thalamus and onward to the primary visual cortex, with parallel pathways to other areas like the superior colliculus. This sequence—capture of light, phototransduction into neural activity, and transmission to several brain regions for processing—is what drives visual perception. The idea that the frontal cortex interprets visuals immediately is incorrect because the primary interpretation happens in the visual cortical areas, not the frontal cortex. The notion of converting photons into sound signals or generating activity before light exposure contradicts how sensory processing and neural activation work.