WEEK 3 FORUM-eye
ASSIGNMENT NO LESS THAN 300 WORDS
Many people wear glasses to compensate for the fact that the optical system of their eye does not focus a sharp image on the retinas. Once you have reviewed the videos below, discuss at least three of the disorders of focusing. Be sure that you are discussing the complete epigenetic origin which should include a discussion of the genetic/biological origin and the environment influence related to these disorders of focusing. Include in your discussion the impact of culture in the development of the optical system at various stages of the lifespan. Support your belief and use specific examples.

READING
PSYC304| LESSON 3: VISUAL PERCEPTION: NEURAL SELECTIVITY
Introduction
Topics to be covered include:
Lateral inhibition
Single fibers of an optic nerve
The role of feature detectors in visual information processing and perception
Where information goes when it is processed and sent to the brain
How forms of visual agnosia show us the importance of parts of the brain
Why it is important to understand distributed representation
In this lesson, we will look at how the visual systems identify and process information in greater depth. Light is processed and changed as it moves through visual systems to reach the brain. The information is then interpreted by the brain, meaning the exact visual stimulus initially encountered as a distal stimulus is not completely the same once it is processed by the brain. This lesson will explain the different processes that occur and move the information from the eye to the brain.
Electrical Signals
For this lesson, let us take a trip to the store. When you go grocery shopping, think about how you accomplish the goal of getting everything on your list. Is it a straight line, or do you weave in and out of aisles as you put different types of groceries in your cart? If you only go to the store for one item, a straight line might work, but I’m not sure anyone could exist on just one item to eat for the entire week. The point is that the straight line would be fairly one dimensional and would not provide you with the variety of foods you need.
This is true for electrical signals too. Signals sent to the brain from receptors do not go directly to the brain from the receptor in a straight line. The information that is sent to the brain gets there via the signals of many neurons responsible for different aspects of the initial sensory image. This interaction of the signals of multiple neurons is called neural processing (Goldstein & Brockmole, 2017).
Now, imagine you are in the middle of the store when an end cap full of potato chips falls over leaving mess everywhere. At the time of this incident, 20 people were clustered together nearby. Each one saw something different about this incident. You were in this cluster and caught this incident out of the corner of your eye. You did not directly see it, but did see some and had a good idea of what else happened. By the time you think about it later, the image you pull up seems more complete somehow. Your brain added some details to create a complete picture for you.
Inhibitory Processes in the Retina
When an image is transmitted to the retina, it is processed through a layer of photoreceptors, or neurons that measure light intensity, and alter this information into something that can be processed by the rest of the nervous system. Different photoreceptors correspond to different light points in the observed stimulus. Photoreceptors that correspond to brighter areas of a stimulus process an increased amount of light, which results in larger signals when compared to photoreceptors that correspond to darker areas of a stimulus. This information is then processed in different ways in different interactions with different neurons within the retina. The photoreceptors generate signals based on the amount of light they are receiving, which means signals will be different based on different amounts of light (Grobstein, 2017).
LATERAL INHIBITION
Lateral Inhibition refers to the inhibition that neurons have on one another and how this inhibition is transmitted across the retina in order to increase contrast between dark and light areas to produce a sharper image for the brain (Goldstein & Brockmole, 2017). Think about the endcap of potato chips falling over. If the manager asks what happened and everyone speaks at once, the message becomes blurred as too many people provide information. If only a couple of people speak – preferably people who saw the event from different angles, the picture becomes clearer and more defined. So, how does this work with vision? Output neurons point out to the brain the areas of contrast where light intensity changes quickly, like the light and dark patterns of a checkerboard (Grobstein, 2017).
In a classical study conducted by Keffer Hartline, Henry Wagner, and Floyd Ratcliff