Our nervous system is made up off
of billions of neurons constantly receiving and transmitting information throughout
our entire bodies. A neuron is made up of a cell body and an axon. The human
nervous system process sensory information and executes the motor response. (Gazzaniga)
The neuron which consists of a cell body and axon, along which the information
is being transmitted play a crucial role in information processing. Myelin, a
substance rich in lipid and proteins that surround the axon are found in both
the cells of the central nervous system and the peripheral nervous system.
Glial cells are responsible for the proper formation of myelin along axons. In the
central nervous system oligodendrocytes, a type of glial cells, are responsible
for myelin formation. Schwann cells are synonymous in that they form myelin in
the peripheral nervous system. They are key to the effective transmission of
neural impulses. Myelin sheaths can be
seen as “similar to the coating of an electrical wire that insulates and
protects and helps speed nerve transmission.”(NationalMsSociety)
Damage to the myelin sheath can
have numerous severe complications. One of these complications we can see is in
the demyelinating disease known as Multiple Sclerosis. Multiple Sclerosis is a
disabling condition which effects the brain, spinal cord and optic nerves by
damaging the myelin along these systems. As mentioned before myelin can be seen
as similar to the coating of an electrical wire. When the myelin is therefore demyelinated,
the nerve fibers are damaged and exposed leading to complications in neural transmitting.
Where the impulse can be blocked or delayed. Demyelinating leads to lesions
along the axon, which does not allow for the proper communication between
cells. The effects and severity of MS can all differ depending on which axons
are affected by the demyelination. (Gazzaniga) Symptoms of MS correspond to
which axon is being targeted and demyelinated. If the demyelination of the axon
is taking place in the peripheral nerves, loss of sensation and muscular
contractions can be seen as evident. Similarly when the problem occurs along to
optic nerve, problems with vision occur. “Loss of balance, numbness, fatigue,
incontinence, and uncontrollable rapid eye movements” are just some of the
other symptoms due to Multiple Sclerosis. (MedLinePlus)
Although one concrete cause of MS
is still not known, deficiency in the immune system is understood to be one of
the leading causes resulting in MS. Genetic, environmental and viral causes are
all thought to play a fundamental role in MS. (NationalMsSociety) It is rather
an interplay of all these factors that contribute to Multiple Sclerosis. In MS, the body’s own immune system destroys the
myelin sheath. The destruction of the myelin due to inflammation in various
areas causes scar tissue in those areas thus contributing to the ineffectiveness
of neural transmission and response.
According
to the Mayo Clinic, there is no cure for Multiple Sclerosis. Treatment than
consists of managing the symptoms and slowing down the progression of demyelination.
Various medications can be given to make the symptoms of MS more containable.
Works cited
Gazzaniga, Michael S. Cognitive Neuroscience3rd ed.New York: W.W.Norton
&Company, 2009. Print
Picture Source
http://labs.feinberg.northwestern.edu/brown/about-multiple-sclerosis/index.html
No comments:
Post a Comment