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Visual pathways
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Visual pathways

Images that we look at are captured by our central retina (the fovea), it transforms light energy into a nervous signal. This signal is sent, via the lateral geniculate nucleus (in the thalamus) to the occipital visual cortex (V1 and V2). The information is then sent along specialized pathways that analyse form, colour and motion in an image.

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This different attributes are then analysed byhigher areas in the brain (V3,V4,V5). The results and the integration of these analyses is what allows for a single unitary percept of the image. These are not the only parts of the brain that play a role in the analysis of the visual world that surrounds us. One of these regions is the superior colliculus (situated in the mesencephalon), which allows for the detection of objects that appear suddenly in the visual field (those parts of the visual field that are outside the fovea). The superior colliculus also controls eye movements whose main purpose is to direct vision to a new stimulus (via the motion of the head and the eyes).

Last but not least, a large region of the thalamus, the Pulvinar, is involved in visual intentional processes that allow us to adequately interact with our environment. It is important to note however, that the Pulvinar may be involved in other task as well.