Functions and Roles of the Nervous System

This article discusses the functions and roles of the nervous system in the human body. It explains how the nervous system collects information from sensory receptors and transmits signals to the brain for processing. The article also explores the different parts of the nervous system, including the spinal cord, autonomic nervous system, brain, neurotransmitters, and neurons.

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FUNCTIONS AND ROLES OF THE NERVOUS SYSTEM
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Task 1
Functions and role of the nervous system
The Nervous System
The nervous system is responsible for the
sensory functions in the human body. The
functioning of the nervous system involves
the collection of the information from the
peripheral sensory receptors which monitors
both internal and external conditions of the
body. (Schafer and Stevens, 2015). The
signals are transmitted from the peripheral
nervous system to the brain for processing
by the afferent nerves. The central nervous
system includes; the spinal cord, Autonomic
Nervous System (ANS), brain,
neurotransmitters and the neurons (Colonna,
and Butovsky, 2017).
The brain

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The main functions of the brainstem include;
to relay the information between the body
and the brain, performs a critical function in
controlling the human breathing,
consciousness and the heart, the brain
processes sensory information, and
regulation of blood pressure. The cerebellum
parts of the brain control balance and
coordination (Prossin et al, 2016).
Spinal cord
The spinal cord connects the large portion of
the peripheral and the central nervous
system. The nerve impulse or the
information are transmitted into the brain by
the spinal cord through the sensory neurons.
It pays the function of electric
communication where the electric currents
are conveyed up and down the cord sending
signals and allowing the communication
between the brain and other segments body
segments. The central pattern generators of
the spinal cord which consist of nerves send
signals to the leg’s muscles to allow them to
contract and extend activating the action of
taking step after step. Reflexes are also
involuntary responses due to a stimulus that
involves the nerves of the peripheral nervous
system, brain and the spinal cord (Old, Clark
and Malcangio, 2015).
Autonomic Nervous System (ANS)
The ANS system acts mainly unconsciously
regulating body functions such as digestion,
papillary response, sexual arousal, urination,
heart rate, and respiratory rate. It also
coordinates and controls the mechanism of
fight or flight response. The ANS system
has a sympathetic division that maintains the
homeostasis of the internal organ and
initiates the response of stress (Gordan,
Gwathmey and Xie, 2015).
Neurons
Also called nerve cells or neurons are
electrically excitable in the nervous system
which plays a role in processing and
transmitting the information. Within the

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bodies of the vertebral animals, the neurons
are the core components of the spinal cord,
brain and the peripheral nerves (Sweeney,
Ayyadurai and Zlokovic, 2016).
Neurotransmitters
They are endogenous chemicals which
enhances the neurotransmission. It is the
chemical messenger that conveys signals
across the chemical synapse like
neuromuscular junction and from one
neuron to another muscle cell or targeted
neuron (Kavalali, 2015).
Effects of Stroke in the nervous system
The nervous system comprises of two major
parts; the central nervous system and the
peripheral nervous system (nerves
connecting to other body parts). The effect
of stroke in the body depends on various
factors; the location of the obstruction and
the extent of the brain tissue affected (Berti,
Garbarini and Neppi-Modona, 2015).
. For one side of the body is controlled by
the opposite side of the brain, when stroke
affects one side results to neurological
complications on the side of the human body
its effect. Depending on the injury severity,
a stroke may affect both sides of the body
making the victim to be in a “lock-state.” In
such a state one is generally unable to
converse or make any movement below the
neck. A stroke occurs when the blood is
unable to reach either both sides of the brain
or a particular region of the brain which
controls a particular body functions, and this
leads to non-functioning of the part or both
sides. If the stroke affects at the back of the
brain, it will result in vision disability. When
an individual has a stroke, the nerve cells in
the brain became wounded, and the blood
that carries the oxygen to the brain is
disconnected such that some part of the
brain is unable to get supplied with oxygen.
The brain cells get damaged due to lack of
oxygen and can die if they are left without

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oxygen for a few minutes. After the brain
cells have been damaged the nerve tissue
may not repair itself, and if it does, it can
take a long period of which it may also not
be completely normal. The two poststroke
changes that interfere with the functioning
of the ANS favor the increased activities of
the sympathetic nervous system, and it
decreases the activities of the
parasympathetic nervous system (Bardy et
al, 2015).
Effects of drug on the behavior of a
stroke patient
Stroke medication has several side effects on
the human body. Some of the stroke
medications include; Anticoagulants,
Antiplatelets, statins, blood pressure Meds
and SSRI’s (common antidepressant).
The common side effects of SSRI’s
antidepressants include anxiety, drowsiness,
restlessness, and nausea. The behavioral side
effects of the SSRI’s sometimes gets better
on their own after a few days or weeks
(Dziedzic, 2015).
The blood pressure Meds is a broad class of
medicines whose side effects aren’t severe,
and they stop in time. The body changes due
to these drugs include constipation,
nervousness, coughing, headache, and
diarrhea. Dizziness in general or while
sitting up or standing quickly is a sign of
low blood pressure which is more serious,
and one requires a healthcare provider for
help.
Anticoagulants and anti-platelets have
different effect according to their types, and
the most adverse effect is bleeding. The drug
result to bruising which is a serious problem
that requires a doctor, the antiplatelets
causes’ pain, nausea and stomach upset
(Pinheiro et al, 2016).
The Statins are used to reduce the risk of
stroke and heart attack and keep cholesterol
in check. A stroke patient requires a doctor’s

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guidance and advice once he/she believes
the beginning of the side effects. Sometimes
the patient using the statins experiences
muscle weakness, soreness, pain or
tiredness. In the long term effect, there is a
significant possibility that the drugs may
maximize the level of glucose or cause
diabetes. The healthcare provider is the best
for consulting as the side effect of statins
depends on various situations such as the
prescription time, the dosage or the
conditions of the body of which all have
different side effects (Llorca et al, 2015).

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Task 2
Localization of the brain functions through research case studies
Introduction
This easy is designed to show in details the reason or causes for the localization of the human
brain. The brain function localization is a design that a particular region of the brain comprises of
unique or different function. The behaviors, Ideas, and emotions are all originated from the brain
and in specific locations. The studies of Wernicke and Broca have contributed largely to the
understanding of the general localization of the brain.
Paul Broca conducted a study between 1824 and 1880 which revealed the importance and the
new knowledge and information regarding the functioning of the specific regions of the brain.
The study involved a patient called “Tan” where it was to investigate the unusual language
capability and ability through studying his brain. Through a longitudinal study, Broca carried out
the study investigations to his patient for many years who was called Tan for the reason that
“Tan” was the only sound that the patient could produce. Tan died, and Broca conducted a post-
mortem autopsy on his body and on another patient to find out which part of the brain resulted in
his conditions that caused his critical death. After the post-mortem, Broca got the evidence that
the specific area of the brain was damaged or injured resulte4d to loss of ability to make coherent
speech. The injured part of the brain became to known as Broca’s area. The effects of part of the
brain that is damaged could be observed in the speeches of stroke patients who are permanently
and temporarily incapable of producing the language (a condition called Broca’s aphasia). As per
his study, Broca concluded that the Broca area is the one responsible for the language

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impairment of the patients. Broca’s study led to the rise of new research and understanding of the
localization of brain functions.
Carl Wernicke’s case study in 1874, which was similar to the Broca’s also revealed the
significance and the new information concerning the functions of another specific region in the
brain. Wernicke’s study aimed at investigating the effects of brain damage to the localization of
the function. He investigated comprehensive disorder for he believed that the comprehension of
the language was from a different area other than the Broca’ area. Wernicke’s study involved a
similar procedure as that of Broca by conducting post-mortem autopsies while noting the
behavior to locate the part of the brain damaged after the death of the patient particularly the
stroke victims. The results after Wernicke performed the post-mortem autopsies he concluded
that the was a specific part of the brain that was behind the production of the comprehensive
speech. This section of the brain later came to be tremed as Wernicke’s area. The victims with
the Wernicke’s area aphasia could have problems like substituting the wrong words into the
planned phrases or might experience difficulties in understanding other people’s speeches.
Wernicke now had evidence which shows that the damaged Wernicke’s area was the cause of the
inability to understand the speech and to comprehend although they were able to speak. The
Wernicke study towards the localization of the brain function concluded that the area called
Wernicke’s area is the chief cause of the impairment of understanding the language and
comprehension of the speech. This study came clear to the specific section of the brain which is
responsible for the particular human activities and behavior. However, it was not easy to find
ways of investigating the study further for such cases of brain damage due to infections such as
stroke were very rare. Moreover, the operation of more people while conducting such an
experiment was deemed as unethical (Fischer-Baum, and Tian, 2019).

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The other case study that supports and explains the localization of the brain is that of H.M. who
had a brain injury at an early age. H.M started suffering from severe epileptic spasms, and he
undertook a brain surgery experiment whereby the neurosurgeon detached some tissue from the
medial sequential lobe together with the hippocampus. Afterward, H.M became ill from
anterograde amnesia, and this made him unable to create new semantic and episodic memories.
Nevertheless, H.M was able to get some new knowledge of procedural memories. According to
the H.M case study, several conclusions were made regarding the localization of the brain
functions. The study showed that hippocampus and the neighboring parts have a vital role in
transmitting quick-fix memories into long-standing memory storage. Also, the practical
memories were neither related nor stored within the hippocampus. The H.M case study also
aligns with the idea that the human brain consists of several memory systems that are sustained
by distinctive brain sections and the hippocampus is not the only special structure that is
involved in the storage of memories (Cubelli, 2019).
Conclusion
According to the explanations, results, analyses of discussion and conclusion of the three case
studies of Wernicke, Broca and H.M they all link to one outcome about the specificity in the
brain localization. The three case studies are relevant to support the understanding of how the
brain performs separate functions in relation to its regions/ parts. Through the connection of the
three studies, there is a description of how one part of the brain could be injured resulting in a
specific impact on a particular function of the brain.

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