Somatic Nervous System

The nervous system is the main driving force of any human being. Humans share their emotions & do different jobs with the help of the nervous system. The brain is the main component of this nervous system. Scientists have divided the nervous system into two primary components. One is Central Nervous System & another is Peripheral Nervous System. Central Nervous System or CNS developed with the brain & spinal cords. These are the component that controls all the activities of the nervous system. Also, these can be referred to as the main warehouse of the nervous system. Peripheral Nervous System or PNS is the other part of the nervous system. This part is developed with the help of a large network of nerves. This part helps to execute & transport the commands from the CNS to the particular target area. Somatic Nervous System is one of them.

What is Somatic Nervous System?

Somatic Nervous System is a component of the Peripheral Nervous System. As Somatic Nervous System falls under the PNS, so there is no commanding organ present. this is the network of nerves. These nerves are transporting the messages from the CNS to the target cells. After transporting the messages there, a particular action is taken there. Generally, the target cells of the Somatic Nervous System are Skeleton Muscles. These are the muscles that are associated with the movement of the skeleton. These muscles are present all over the body.

In human hands or legs or any other part of the body, there will be skeleton muscles. These are the muscles that control the movement of the outside components. Somatic Nervous System controls the voluntary movement of the muscles. This means, if it receives the command from the CNS, then only it can able to execute the action. Another part of the PNS, like the Autonomic Nervous System, can execute actions involuntarily. This means without the proper command from the CNS, it has the authority to execute some actions on target cells. In Somatic Nervous System, there is no way to execute actions without a proper command from the CNS.

What is Somatic Nervous System made of?

Somatic Nervous System is the component of the Peripheral Nervous System. In this type of nervous system, there is no type of structure or cells present like in other parts of the body. The Somatic Nervous System is a complete chain of Neurons. But still, there are some more things there. They completely build the Somatic Nervous System.

• Neurons: This is the most important thing in the nervous system. The nervous system has only this type of cells there. The main function of the Neurons is to collect electrical signals & transport them to all parts of the body. The neurons are also made with some divisions.
  • Cell Bodies: This is the main component of the neurons. This is the place from where structures are initiated to accept the electrical signals & transport them. The cell Body is a circular structure inside of the neurons.
  • Dendrites: These are small branch-like structures. These come from the cell bodies. There are many dendrites are present. the main function of this is to accept the electrical signal from the parts of the body. Or sometimes this collects signals from other neurons as well.
  • Axon: This is a large structure compared to the Dendrites. It is also derived from the cell bodies. Their job is to transport the electrical signal from the cell body to other neurons or targeted cells. There is only one Axon per neuron present.
  • Layer: There is a special layer on the neurons. They are known as Myelin. This is the thick, fat layer on the neurons. This helps to protect the neurons. Also, this helps to transport electrical signals.
• Nuclei: This is a complex structure. It is completely made with different neurons. This is the weblike structure in the Somatic Nervous System. They act as the connection place of the neurons. Their job is to transport the electrical signals.
• Glial Cells: This is another cell present in the Somatic Nervous System. Though they don’t have any contribution to electrical signal transport. At the young stage, from the Glial Cells, the neurons are created. Also, this helps the nervous system from any infection. Also, it creates the myelin layer for protecting it from dangers.
• Ganglia: Ganglia is an example of closely related cells of the nervous. When the nerve cells are close enough & made a complex structure is known as the Ganglia. The Cochlear Ganglia is one of them. it is situated inside the ears. It helps to keep balance & to hear.

Components of the Somatic Nervous System

Somatic Nervous System is completely made of neurons. There are no other cells present inside the Somatic Nervous System.  But based on the functionality, scientists have divided them into two categories. These categories help to identify the electrical signal movement from the CNS to the target cells.

• Motor Neurons or Efferent Neurons: These are the neurons that transport the signal from the CNS to the target cells.
• Sensory Neurons or Afferent Neurons: These are the neurons that transport signals from the target cells to the CNS.

Motor Neurons or Efferent Neurons

Motor Neurons are those neurons that receive electrical signals or commands from the CNS. Then those electrical signals travel to the targeted skeleton muscles. After that, there will be some actions will be performed. As these neurons transport the electrical signals from the CNS to the far away targeted cells, these neurons are often termed Efferent Neurons. Generally, these neurons are originated from the spinal cord of the CNS. Motor neurons should be always originated from the front side of the spinal cord. This means they will be associated with the ventral side of the spinal cord. 

Inside the spinal cord, the motor neurons are originated from Gray Matter. Inside the Gray Matter, there are only the cell body & dendrites are present. And all the axons are present outside of the spinal cord. So the axons are referred to as the PNS. As axons are not inside of the CNS system. Whenever the electrical signal moves to the targeted cells, a special neurotransmitter will be secreted. This is known as Acetylcholine. Acetylcholine secretes from the synaptic cleft of the neurons—this chemical triggers the skeleton’s cells to perform certain tasks.

Sensory Neurons or Afferent Neurons

Sensory neurons are opposite of the Motor Neurons. They transport the electrical signals from the targeted cells to the CNS. After receiving the signals from the CNS, it provides again some commands via the Motor neurons. As these neurons transport the signal from the targeted cells to the CNS, these are also termed Afferent neurons. These neurons are originated from specifically targeted cells. After originating, one single axon will carry the electrical signal to the CNS.

These neurons end in the spinal cord. They are ends in the Gray Matter. But their ending location is different from the originating location of Motor Neurons. They generally end up in the dorsal side of the spinal cord. This means they will end up in the back side of the spinal cord. Inside the spinal cord, there will only end part of the axon. The dendrites & cell bodies will locate near the skeleton muscles to pick up the electrical signals. These electrical signals come from the environment. This stimulation helps to create an electrical signal there.

Importance of the Somatic Nervous System

The somatic Nervous System is very important in the human body. They are completely associated with the movement of our body parts. In absence of the Somatic Nervous System, humans can’t able to move their hands, legs, etc. this helps them to run, walk, type a character, etc. Humans use their fingers to hold any object. This is also performed by the muscles & Somatic Neurons. Also, the reflex action is provided by the somatic nervous system. These are also important tasks performed by this component. Without any command from the CNS, this nervous system promptly acts. As this nervous system is a voluntary nervous system, there is a command needed to move any body parts. But in the case, of reflex action, there is no proper command is needed. For all these reasons, the somatic nervous system is very important.

Difference between SNS and ANS

Somatic Nervous System	Autonomic Nervous System
Somatic Nervous System is responsible for the voluntary movement of the body.	Autonomic Nervous System is responsible for the involuntary movement of the body.
Somatic Nervous System operates or influences the skeleton muscles.	Autonomic Nervous System operates or influences the cardiac muscles, smooth muscles, etc.
The somatic Nervous System helps to detect the environmental stimulus. Like touch, light, smell, etc.	Autonomic Nervous System helps to detect internal stimulations. Like blood pressure, salinity, etc.
Somatic Nervous System is made with only a thick layer of myelinated layer.	Autonomic Nervous System has both thick & thin layers of the myelinated layer.
There is only one single neuron present in Somatic Nervous System. This neuron is present between the CNS & the target cell.	There are two neurons are present in Autonomic Nervous System. One is from CNS to the ganglia & another is from Ganglia to the targeted cell.

Mechanism of Somatic Nervous System

The main function of the somatic nervous system is to move body parts as per the command of the CNS. It uses two types of neurons to perform this. At first, the CNS commands the in form of electrical signals. These signals come to the dendrite of the Motor Neurons. With the help of the Motor Neurons, these signals travel to the targeted cells. There is performs necessary actions. Sometimes a stimulus in the muscles takes the form of an electrical signal. Those signals trigger the dendrites at the skeleton muscles. Then those electrical signals travel the path & come to the CNS. CNS then decodes the signal.

If a person wants to fold his arms. Then the CNS will send the signal to the muscles of the arm. This signal transports with the help of the Motor Neurons. Acetylcholine will be secreted from the end of the Motor Neuron. This will stimulate the muscles of the hand & then the hand will be folded. This can be in reverse order also. If a person has an injury to their leg. Then the Sensory Neurons will take that stimulation in form of an electrical signal. Those signals travel to the CNS. Then CNS decodes the signal & understands the situation. In this way, the whole mechanism works there.

Functions of Somatic Nervous System

Somatic Nervous System is the nervous system that helps to sense or helps to make communication with the environment. So, for that purpose, Somatic Nervous System has two functions. Or Somatic Nervous System usually performs two different works.

• Sense the Environment: Somatic Nervous System helps to sense the Environment. It helps to take the inputs from the environment. Whatever the input form is. That might be a touch, smell, noise, etc. All the inputs will be received by the Somatic Nervous System. The backside of the human will take the touch inputs using the Somatic Nervous System. Then they move to the spinal cord. From the spinal cord, it moves to the brain.
• Movement Of Body Parts: The human body movement is controlled by the Somatic Nervous System. The brain provides the command. Those commands using the Somatic Nervous System move to the targeted area. There, they help to move the muscles. The muscles will help to move the body part. In this way, the Somatic Nervous System helps to move the human body.

Reflex Action

Reflex actions are those actions that occurred involuntarily. If there is any threat or any proper stimulation, then without any command or signal, muscles play a prompt action. This action is known as the Reflex Action. There are many reflex actions are present. Like suddenly bringing any element near to the eye, will promptly close the eye. This is the reflex action. Mainly Somatic Nervous System controls the reflex action.

It is the combined work of Motor Neurons & Sensory Neurons. The Sensory Neurons will sense the stimulus & then send the electrical signal to the CNS. CNS receives the signal & then decodes them to read the message. After reading the message, it sends a signal to the targeted cells to perform a certain action. This signal is transported with the help of the Motor Neurons. Two types of reflex mechanisms are present. In one case, there is another neuron in between the Sensory Neuron & Motor Neuron. This neuron is present inside the spinal cord. This is known as Polysynaptic. As there is more than one synaptic cleft or neuron joining in this path. Another is Monosynaptic. In this case, the Sensory & Motor neurons connect directly inside the spinal cord. There is only one synaptic cleft present in this case.

How Does The Somatic Nervous System Help With Other Organs?

Somatic Nervous System can only be responsible for controlling the outer body parts. This means they can be able to control the body parts which are located outside of the body. This means the hand, leg, etc. They don’t have any connection with the internal muscles. But sometimes they can able to interact with internal muscles. Like during the time of a heart attack, an individual finds pain in the left arm, backside, or at the abdomen. This is kind of a referred pain. This means the actual process is going on the muscles of the heart. But they are the reflection of the pain.

Also, there is another example. Usually, humans take breathe normally. For taking a breath they don’t need to think about it. As breathing is controlled by the Autonomic Nervous System. But sometimes, a human can breathe as per their wish. Also, sometimes humans can able to hold their breath. This can be done with the help of the Somatic Nervous System.

Disorders that Affect Somatic Nervous System

Somatic Nervous System is part of the Peripheral Nervous System. They are not part of the Central Nervous System. This means they don’t belong to the brain & spinal cord. But they are the most important for sensing the stimulus & performing certain tasks. Sometimes certain diseases bring the disorder to the Somatic Nervous System. There might be a lot of diseases. Some common diseases are:

• Type 2 Diabetes: Persons who are affected with type 2 Diabetes have the probability of losing control of the Somatic Nervous System. For those patients, it is quite common that they can’t able to since their limbs. This means the Somatic Nerves in their limbs stop working. 
• Guillain-Barré Syndrome: This is a disease where the immune system of the body damages the neurons. This is a very rare case. This causes autoimmune problems. And the nervous system witnesses an intense inflammation three.
• Infection: Some bacteria or virus causes this problem. HIV damages the nervous system of the body. This causes severe disease of the nervous system. Also, the nervous system starts degrading with time.
• Side effects Of Medicines: Some medicines for critical diseases have some side effects on the Somatic Nervous System. Sometimes chemotherapy for cancers also causes problems for the nervous system. Sometimes side effects arise from the surgery point.
• Exposition To Toxins: Sometimes some heavy metal acts as a toxin for Somatic Nervous System. Mercury is a very toxic material for the human body. Exposition to these metals can cause the probability of having disorders.
• Leprosy: This is another disease that might cause disorders in the Somatic Nervous System. In this disease, the skin burns & the outer layer of the skin is degraded. In the severe form of this disease, an individual has some problems with the Somatic Nervous System.
• Genetic Disorder: Sometimes disorder to the Somatic Nervous System comes from inheritance. Like this symptoms can be inherited from the parents. In this case, a child takes birth with a disorder in its Somatic Nervous System.
• Due To Accident: Sometimes due to an intense accident, some individuals can get big injuries. If the injury is large & big enough, then it might damage the Somatic Nervous System. Sometimes from the injury, swelling can develop. in such cases, there might be intense pressure on the Somatic Nervous System.
• Cancer: Sometimes, when an individual is affected by cancer, their cells get an increased growth rate. In those cases, they will make damage the Somatic Nervous System. Those will interrupt the sensing using the Somatic Nervous System.

Symptoms of Body Organ Conditions

For any reason, if the sensory neurons got affected inside of the Somatic Nervous System, then there are a lot of symptoms are present.

• Loss Of Sense: Due to damage to the Sensory Nervous System, the sensory nervous will not work more. For that reason, there might be a deficiency in a sense. Also, it will create a problem for every daily life routine. Individuals affected by such damage can’t able to pick up anything. As they can’t able to sense that thing.
• Tingling: This is also known as Numbness. Or sometimes it is known as Paresthesia. In this case, the muscles completely stop responding. With the help of the needle, doctors check the condition of the damages. This is the severer step of the loss of sense.
• Neuropathic Pain: This is a type of pain that causes sometimes severe pain. In any part of the body, like sometimes in the leg severe pain occurs. This pain is so intense that it can create a problem for any individual’s daily routine life.

If the motor neurons are affected instead of the sensory neurons, then the symptoms will be completely different. In that cases, individuals will witness different problems like

• Loss Of Control: Motor neurons send a signal to the targeted cells. if this is damaged, then there will be no control of the nervous system. In those cases, loss of control is a major symptom. Sometimes, individual losses the body balance and also the motor neuron damage.
• Shrinking Of Muscles: As there is no longer control of the neurons to the muscles, there might be a shrinking of the muscles. This will happen as there is no operations are not performed on the skeleton muscles. This is often known as Wasting.
• Cramp To The Muscles: Due to the absence of the motor neurons or damage to the motor neurons, the muscles will sometimes act as per their condition. At that time the cramp in the muscles is a very common thing. Sometimes spasms and twitches also happen there.

Treatments for Somatic Nervous System Problems

There are some basic treatments for repairing the damage caused to the Somatic Nervous System. As it is important for the survival of daily life. These treatments will take time to repair the damages. But there is a high probability that an individual will survive & repair the Somatic Nervous System damage by using these methods.

• Meditation: Sometimes meditation helps a lot in these cases. If the problem is not a big one, then doctors prescribed some meditation to the individual. This will help to calm down the Somatic Nerves & related problems.
• Physical Therapy: This is also a way to reduce the pain of the Somatic Nerves. In these cases, am an expert rub the area of the pain. So that the Somatic Nerves get a chance to repair its damages. Rubbing properly will surely help to reduce pain.
• Surgery: Sometimes a nerve gets locked inside of the swelling due to some accidents. The surgery is only a way then. They will remove the nerve from the swelling or the tissue.
• Electrical Nerve Stimulation: This is a process where an electrical signal is provided to the malfunctioning neurons. Sometimes these mild electrical signals help to recover the damage caused to the Somatic Nervous System.
• Acupuncture: This is the traditional Chinese process of recovery. In this case, small needles are inserted into the different locations of the muscles. In this way, this helps to gain the senses back & nerves start working. This process is widely used nowadays.
• Nerve Ablation: This is another therapy. In this case, a nerve that is damaged is intentionally removed. By providing some signals to the nerve, this device will completely damage the nerve. This will help to reduce the pain.
• Wearing Different Products: If the problem is not so much serious, then the doctor will prescribe some unique wearable things. Sometimes, they prescribed unique footwear. Sometimes a brace will help to improve the condition of the pain.

FAQs on Somatic Nervous System

Question 1: Does Somatic Nervous System belongs to the Central Nervous System?

Answer:

No, Somatic Nervous System belongs to the Peripheral Nervous System. The CNS is developed with the Brain & Spinal Cord. Somatic Nervous System has only one end that is attached to the CNS.

Question 2: What are the divisions of the Peripheral Nervous System?

Answer:

There are two divisions in Peripheral Nervous System. One is Somatic Nervous System & another is Autonomic Nervous System. Somatic Nervous System is liable for voluntary actions. And Autonomic Nervous System is liable for involuntary actions.

Question 3: From where the Motor Neurons of the Somatic Nervous System does originate?

Answer:

Motor Neurons of Somatic Nerves originate from the Gray Matter of the Spinal Cord. But they originate from the ventral or the front part of the spinal cord.

Question 4: From where the Sensory Neurons of the Somatic Nervous System does originate?

Answer:

Motor Neurons of Somatic Nerves also originate from the Gray Matter of the Spinal Cord. But they originate from the dorsal or the back side of the spinal cord.

Question 5: Can the Somatic Nervous System able to influence the internal organ muscles?

Answer:

No, Somatic Nervous System can only able to influence the Skeleton Muscles. These are the muscles that are responsible for moving the outer body parts. There is no influence of the Somatic Nervous System on internal organ muscles.