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The following are my thoughts on how a dysfunction, or irregularity, in a projection pathway could impact everyday life.
Perception is described as our bodies ability to create a mental representation of a stimulus within our environment (Gazzaniga, Irvy & Mangun, 2018). Within the human body, there are multiple projection pathways that feed into our overall view of perception. For example, the auditory pathway is utilized for providing auditory sounds to the brain, the olfactory pathway is utilized to provide information in order to perceive smells, and the somatosensory pathways provide the perception of stimuli impacting the body, such as pain (Gazzaniga, Irvy, & Mangun, 2018). However, there is one projection pathway that our body relies on heavily in order to perceive a stimulus, and that is vision.
Visual information is provided to our brain via photo receptors within our retina. In order for visual information to reach our brain, it follows a process, In short, light reflected off of objects reaches our retina causing photopigments to break down. This breakdown of photopigments results in a chemical change which then triggers an action potential, which will result in the transmission of a neuronal signal to our brain via the thalamus (Gazzaniga, Irvy, & Mangun, 2018). However throughout the processing process, the information is projected into a number of visual processing areas beginning with the primary visual cortex of the occipital lobe, or V1, and moving into areas such as V2, V3, V4, and so on. According to modern research, each visual area is responsible for processing certain visual information (Gazzania, Irvy, & Mangun, 2018). For example, area V5 appears to be responsible for the processing of movement.
Unfortunately, there are instances in which these particular areas within the brain do not process information correctly. For example, akinetoposia, a condition where one loses the ability to perceive motion within objects, is the result of the V5 area becoming damaged (Gazzaniga, Irvy, & Mangun, 2018). When a person experiences a lesion in the V5 area, they may begin having trouble perceiving an object in motion. For example, a person may have issues perceiving the speed of a car, or become unable to perceive the movement of a football that is thrown to them. This dysfunction of the visual projection pathway could result in a very dangerous life for said individual. The ability to perceive motion is a critical function for safety and survival. Everyday actions such as driving a car, walking across a street, or even cooking food, could potentially become compromised if one is not able to determine if an object is in motion.
