Understanding the Brain

Central nervous system disease

From Cognopedia
Jump to: navigation, search
Central nervous system disease
Classification and external resources
MeSH D002493

A central nervous system disease can affect either the spinal cord (myelopathy) or brain (encephalopathy), both part of the central nervous system.[1] The central nervous system controls behaviors in the human body, so this can be a fatal illness.


Spinal Cord

The spinal cord transmits sensory reception from the peripheral nervous system.[2] It also conducts motor information to the body's skeletal muscles, cardiac muscles, smooth muscles, and glands. There are 31 pairs of spinal nerves along the spinal cord. These nerves each contain both sensory and motor axons. The spinal cord is protected by vertebrae, and connects the peripheral nervous system to the brain, and it acts as a "minor" coordinating center.


The brain apprehends signals from the spinal cord as well as the olfactory nerves (or the first cranial nerve) and optic nerves. It allows the body to function. The brain is protected by the skull; however, if the brain is damaged, the results to the human body can be very consequential.

Types of disease


Encephalitis is an inflammation of the brain. It is usually caused by a foreign substance or a viral infection. Symptoms for this disease include: headache, neck pain, drowsiness, nausea, and fever. If caused by the West Nile virus,[3] it may be lethal to humans, as well as birds and horses.


Meningitis is an inflammation of the meninges (membranes) of the brain and spinal cord. It is most often caused by a bacterial or viral infection. Fever, vomiting, and a stiff neck are all symptoms of meningitis.

Tropical spastic paraparesis

Troby a virus that can also cause leukemia, a disease of the bone marrow.

Arachnoid cysts

Arachnoid cysts are cerebrospinal fluid covered by arachnoidal cells that may develop on the brain or spinal cord.[4] They are a congenital disorder and in some cases may not show symptoms. However, if there is a large cyst, symptoms may include headache, seizures, ataxia (lack of muscle control), hemiparesis, and several others. Macrocephaly and ADHD are common among children, while pre-senile dementia, hydrocephalus (an abnormality of the dynamics of the cerebrospinal fluid), and urinary incontinence are symptoms for elderly patients (65 and older).


Huntington's disease is a rare neurological disorder that is inherited. Degeneration of neuronal cells in the frontal lobe of the brain occurs. There is a progressive decline which results in abnormal movements.[5] Statistics show that Huntington’s disease may affect 10 per 100,000 people of Western European descent.


Alzheimer’s is a neurodegenerative disease typically found in people over the age of 65 years. Worldwide, approximately 24 million people have dementia; 60% of these cases are due to Alzheimer’s. The ultimate cause is unknown. The clinical sign of Alzheimer’s is progressive cognition deterioration.

Locked-in syndrome

Locked-in syndrome is due to a lesion on the brain stem, damaging the pons. It is a condition where the patient is awake, but suffers from paralysis[6] of all or nearly all voluntary muscles of the body and cannot communicate or move. Causes of locked-in syndrome may be: traumatic brain injury, circulatory system disease, nerve cell damage, and overdose of medication.


Parkinson’s affects the motor skills and speech. Symptoms may include bradykinesia (slow physical movement), muscle rigidity, and tremors. Behavior, thinking, and sensation disorders are non-motor symptoms.


Tourette's syndrome is an inherited neurological disorder. Early onset may be during childhood, and is characterized by physical tics and verbal tics. The exact cause of Tourette's, other than genetic factors, is unknown.

Multiple sclerosis

Multiple sclerosis (MS) is a chronic, inflammatory demyelinating disease, meaning that the myelin sheath of neurons is damaged. Symptoms of MS include: visual and sensation problems, muscle weakness, and depression.



Any type of traumatic brain injury (TBI) or injury done to the spinal cord can result in a wide spectrum of disabilities in a person. Depending on the section of the brain or spinal cord that suffers the trauma the outcome may be anticipated.


Infectious diseases are transmitted in several ways. Some of these infections may affect the brain or spinal cord directly. Generally, an infection is a disease that is caused by the invasion of a micro-organism or virus.


Degenerative spinal disorders involve a loss of function in the spine. Pressure on the spinal cord and nerves may be associated with herniation or disc displacement. Brain degeneration also causes central nervous system diseases. Studies have shown that obese people may have severe degeneration in the brain due to loss of tissue affecting cognition.

Structural defects

Common structural defects include: birth defects,[7] anencephaly, hypospadias, and spina bifida. Children born with structural defects may have malformed limbs, heart problems, and facial abnormalities.


A tumor is an abnormal growth of body tissue. If benign, tumors can be non-cancerous, but if they are malignant, they are cancerous. In general, they appear when there is a problem with cellular division. Problems with the body’s immune system can lead to tumors.

Autoimmune disorders

An autoimmune disorder is a condition where the immune system attacks and destroys healthy body tissue. This is caused by harmful substances, called antigens.


A stroke is an interruption of the blood supply to the brain. Approximately every 40 seconds, someone in the US has a stroke.[8] This can happen when a blood vessel is blocked by a blood clot or when a blood vessel ruptures, causing blood to leak to the brain. If the brain cannot get enough oxygen and blood, brain cells can die, leading to permanent damage.

Signs and symptoms

Every disease has different signs and symptoms. Some include: persistent headache, loss of feeling, memory loss, loss of muscle strength, tremors, seizures, and slurred speech. One should seek medical attention if affected by these.


There is a wide range of treatments for central nervous system diseases. These can range from surgery to rehabilitation or prescribed medications.

See also

External links


  1. "Nervous System Diseases". http://www.healthinsite.gov.au/topics/Nervous_System_Diseases. 
  2. "Organization of the Nervous System". http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/P/PNS.html. 
  3. "West Nile Virus". http://www.medicinenet.com/west_nile_encephalitis/article.htm. 
  4. "How the Brain Works". http://arachnoidcyst.org/functions.php. 
  5. "Huntington's Disease". http://www.hdsa.org/living-with-huntingtons/family-care/stages-of-hd.html. 
  6. "Locked-In Syndrome". http://www.ninds.nih.gov/disorders/lockedinsyndrome/lockedinsyndrome.htm. 
  7. "Birth Defects". http://kidshealth.org/parent/system/ill/birth_defects.html. 
  8. "Stroke". http://www.hearthealthywomen.org/index.php?view=article&id=581.