You will be responding to a discussion board post. This post should be 80% you, and then facts found from other sources. Its not opinionated. It needs to have critical thinking. 125 Word minimum, APA format, cited. It needs to pertain to the paragraph and what the paragraph says. Other things can be added in as well, but make sure it is not just random facts. Below is the paragraph you will be responding to:
1. Student submitted a thorough, informational and clear response that advanced the discussion with detail. Critical thinking about topic was included.
2. Assignment submitted on time and on a different day than other posts. Assignment met 125 word count minimum.
3. Appropriate scientific college-level sources were used. Post contained APA formatted references and in-text citations. The post was grammatically correct.
Hello Classmates and professor,I chose "What is a Homunculus ( sensation and motor)" for my week 1 discusion. Scientists can map which parts of the brain control various parts of the body. The mapping is done by stimulating the sensory or motor cortex with a weak electric current. The stimulation often produces tingling or movement in part of the body.The cortical homunculus visually portrays the anatomical divisions of the primary motor cortex and the primary somatosensory cortex. It represents how our body is perceived within the brain and how the neurons are distributed in these areas in order to create this perception. What immediately stands out is that the size of a body area is not proportional to its representation in the cortical homunculus, certain areas such as the hands, lips and face occupy disproportionately large areas of the cortex, due to the importance of fine motor skills and and the extensive innervation of these areas. Each cerebral hemisphere includes primary motor cortex that is located just anterior to the central sulcus (a.k.a., precentral gyrus) and extends down to the sylvian fissure. This area is histologically known to be Brodmann's Area 4. The topographical representation of the homunculus is arranged in an anatomical fashion and represents the contralateral side. This means that the primary cortex in the right cerebral hemisphere represents motor activity on the left side of the body and vice-versa. It is important to recognize that the density of receptors for various parts of the body are not the same which is why the homunculus represents different sizes as it extends over the cortex. Each cerebral hemisphere includes somatosensory cortex that is located just posterior to the central sulcus (a.k.a., postcentral gyrus) and extends down to the sylvian fissure. This area is histologically known to be Brodmann's Areas 1, 2, 3. The topographical representation of the homunculus arranged in an anatomical fashion and represents the tactile representation of the contralateral side. It is important to recognize 2 main things about the somatosensory cortex; that the density of receptors for various parts of the body are not the same which is why the homunculus represents different sizes as it extends over the cortex, also the surface area of the anatomical body part also does not influence the amount of the cortex dedicated to that body part, but rather reflects the density of cutaneous tactile receptors dedicated to that body part. For example, the lips make up a small surface area compared to other body parts but yet has a greater density of receptors compared to the shoulder or forearm (Busti & Kellogg. 2015).
Word Count: 429
Anthony J. Busti, MD, PharmD, FNLA, FAHA and Dylan Kellogg, MD "Homunculus: Somatosensory and Somatomotor Cortex" (September, 2015) https://www.ebmconsult.com/articles/homunculus-sen...
"Cortial Homunculus" http://anatomyzone.com/anatomy-feed/cortical-homun...