Introduction
The primary neural mechanisms which produce movement start in the brain and continue through the nervous system carrying signals to the muscles. The primary motor cortex is part of the brain located in the frontal lobe which contains subsections of motor neurons purposed for specific motions (Boudreau et al, 2013). The primary motor cortex has sections which control each part of the opposite side of the body. When the left side of the primary motor cortex fires, the signal crosses the body’s midline activating skeletal muscles on the right side of the body with the signal continuing through the nervous system to the muscles of the area of the body being moved. There are also secondary motor cortices which are part of the motion control proceeds. Posterior parietal cortex, premotor cortex, and the supplementary motor area make up the secondary motor cortices. These areas control or assist with complex movement such as movements which would be considered head eye coordination.
The idea is the more brain matter devoted to a certain area of control the more control the person has. As a result, as an athlete trains the athlete develops more control by the brain growing in the specific area of the primary motor cortex the movement is controlled by (Futagi, 2017). Brain improvement caused by an athlete training could lead to an increase in brain matter, a thickening of the brain tissue or an increase in ruffles/layers of the brain area.
The main pathway for control of movement is from the primary motor cortex and the secondary motor cortices’ signals sent through the corticospinal tract (Wasaka, Kida, Nakata, Akatsuka, & Kakigi, 2007). The corticospinal tract is a network of fibers which connect the brain to each section of the spine where the signal then travels through the nerves to the appropriate muscles to be moved. Wasaka, Kida, Nakata, Akatsuka, and Kakigi’s (2007) demonstrates the separation and interaction of both hemispheres with the signals of the left hemisphere controlling the right hand and the right hemisphere controlling the left hand.
Neurological Motor Dysfunction
Like other neurodegenerative disorders neurological motor dysfunction is a degenerative disease which will continue to irreversibly progress in limiting the patient’s ability to control movement (Yamamoto, Lucas, & Hen, 2000). This happens through the destruction of part of the neural mechanical process. For example, Parkinson’s disease has been found to effect basal ganglia structures blocking communication from the brain to the desired muscle (Stern, Mayeux, Rosen, & Ilson, 1983).
As the communication from the appropriate sections of the brain such as the primary motor cortex and secondary motor cortices the brain becomes in part or completely unable to communicate with the desired muscle causing the person not to be able to control movement. For example, someone with Parkinson’s disease will overtime no longer be able to control the movement of their hand to be able to pick up or hold a glass. Valsasina et al. (2011) discovered in the case of Multiple Sclerosis the connections from the muscles to the brain have increased conductivity demonstrating the failure in communication might be more complicated than a simple disconnect. No matter the cause, the outcome of neurological motor dysfunction is the eventual loss of being able to control voluntary movement.
Conclusion
In conclusion, specific sections of the brain including the primary motor cortex and secondary motor cortices control the initiation and sending command signals instructing the movement of muscles. These commands start in the brain, travel through the spinal cord via the corticospinal tract, then to the muscles through the nervous system. As a person practices a specific action the appropriate section of the brain which controls the action’s type of movement can improve. As a person practices and realizes improvement in motion control the improvement is realized by that section of the brain growing, thickening or increasing in folds. As a section of the brain controlling movement diminishes for any reason control of movement is lost causing Neurological Motor Dysfunction.
Neurological Motor Dysfunction is the decreasing ability of a person to control voluntary movement eventually leading to complete loss in control. Diseases which cause Neurological Motor Dysfunction include but are not limited to Parkinson’s disease and Multiple Sclerosis.
References
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Futagi, Y. (2017). Eye-Hand-Mouth Coordination in The Human Newborn. Pediatric Neurology, 75, 43–47. https://doi-org.lopes.idm.oclc.org/10.1016/j.pediatrneurol.2017.06.009
Magill, R. A. (2014). Motor Learning and Control: Concepts and Applications (10th ed.). New York, NY: McGraw-Hill. ISBN-13: 9780078022678
Stern, Y., Mayeux, R., Rosen, J., Ilson, J. (1983). Perceptual Motor Dysfunction in Parkinson’s Disease: A Deficit In Sequential And Predictive Voluntary Movement. Journal of Neurology, Neurosurgery, and Psychiatry. 46, 145-151
Yamamoto, A., Lucas, J. J., Hen, R. (2000). Reversal of Neuropathology and Motor Dysfunction in a Conditional Model of Huntington’s Disease. Center for Neurobiology and Behavior Columbia University. Vol. 101, 57–66
Valsasina, P., Rocca, M. A., Absinta, M., Sormani, M. P., Mancini, L., De Stefano, N., … Filippi, M. (2011). A Multicentre Study of Motor Functional Connectivity Changes in Patients with Multiple Sclerosis. European Journal of Neuroscience, 33(7), 1256–1263. https://doi-org.lopes.idm.oclc.org/10.1111/j.1460-9568.2011.07623.x
Wasaka, T., Kida, T., Nakata, H., Akatsuka, K., & Kakigi, R. (2007). Systems Neuroscience: Characteristics of Sensori-Motor Interaction in The Primary And Secondary Somatosensory Cortices in Humans: A Magnetoencephalography Study. Neuroscience, 149, 446–456. https://doi-org.lopes.idm.oclc.org/10.1016/j.neuroscience.2007.07.040