Visual pathway

Do you know how the visual information reaches the brain after light is transformed into neural signals in the retina?


Have a look at this picture!

An optic nerve starts from each eye and propagates neural signals through the optic chiasm into the neurons of the two Lateral Geniculate Nucleus or LGNs.

LGN are located in the thalamus, a region of the brain that is placed deep inside our head.

LGNs neurons then directly communicate with neurons in the primary visual cortex (V1) of the corresponding brain hemisphere.

Something interesting however happens in the optic chiasm: the two optic nerves meet and exchange fibers in such a way visual information coming from the left half of the visual field is propagated to the right hemisphere and vice versa.

The visual cortex in each of your two hemispheres is responsible for processing the information that comes only from the opposite half of your visual field!