How The Eye Works

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In the daily lives of humans we often take our ability to see for granted. We rarely think about what process our eyes and brain must complete in order to view something as simple as a movie or lecture slide. In fact, such a small part of our anatomy is made of greatly complex procedures The operation system of the eye is very complex and one can easily stray from track when discussing how the eye works. First, the cornea is a part of the physical eye that helps reflect and bend light in a way that makes it possible for it to pass through the pupil, which lies in the center of the iris. The image is focused by the lens and cornea which is then projected in an upside down position onto the retina. The retina may well be the most important …show more content…
The first area of the brain to receive input from ganglion cells is the lateral geniculate nucleus of the thalamus. From there the thalamus sends information to the primary visual cortex in the occipital lobe and area V1 sends information back to the thalamus. These two areas feed information back and forth. Area V1 also sends information to the secondary visual cortex (V1) which then relays that information to different areas of the brain. The ventral stream runs along the occipital cortex to the temporal cortex, while the dorsal stream runs along the occipital cortex to the parietal cortex. The cells in the inferior temporal cortex respond to objects. It allows the brain to identify certain objects. When this area is damaged there is an inability to recognize objects, also known as visual agnosia. Someone with visual agnosia may be able to describe and object and even point it out, but would not be able to tell you what that object is. The fusiform gyrus in the inferior temporal cortex along with the occipital cortex, anterior temporal cortex and the prefrontal cortex are all areas that to do with face recognition. Therefore, when one of these areas is damaged a patient may have trouble recognizing faces; a disorder called prosopagnosia. Area V4 perceives color, therefore without this area we would not be able to perceive something as the same color if it was in a different type of lighting, and it would change color to us, despite its constancy. Area V5, also known as area MT (middle temporal cortex, along with MST (medial superior temporal cortex) receive a lot of their input from the magnocellular pathway. This allows us to perceive motion in our environment. Area MT detects changes in acceleration or deceleration, while MST responds to movements in our environment relative to its

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