CHAPTER 12CHAPTER 12
The nervous systemThe nervous system
By Bernita CamperBy Bernita Camper
The suffix -plegia means paralysis thatThe suffix -plegia means paralysis that
occurs on only one side of the bodyoccurs on only one side of the body
The suffix –itis is very common. It meansThe suffix –itis is very common. It means
Hemiplegia is the partial or total paralysis
of one side of the body. If it is partial
paralysis then the body still allows
weakened movement to occur, such as
limited hand movement.
Hemiplegia can be present at birth or it
can occur at any point after birth.
It is usually a result of an injury or
disease to the motor part of the brain.
Usually damage to blood flow in the brain.
Facial hemiplegia- a paralysis of oneFacial hemiplegia- a paralysis of one
particular side of the face, usually veryparticular side of the face, usually very
noticeable in stroke victims.noticeable in stroke victims.
Cerebral hemiplegia- Occurs when a brainCerebral hemiplegia- Occurs when a brain
lesion disrupts the flow of blood to thelesion disrupts the flow of blood to the
Spinal hemiplegia- Caused by lesions thatSpinal hemiplegia- Caused by lesions that
have formed on the spine.have formed on the spine.
The most common cause of hemiplegia isThe most common cause of hemiplegia is strokestroke. A. A
stroke occurs when a blood clot blocks normal blood flowstroke occurs when a blood clot blocks normal blood flow
to the brain or when a blood vessel breaks, which canto the brain or when a blood vessel breaks, which can
cut off or disrupt blood flow.cut off or disrupt blood flow.
Stroke is the main cause ofStroke is the main cause of cerebral palsycerebral palsy, which in turn is, which in turn is
another cause of hemiplegia.another cause of hemiplegia.
Perinatal strokes, which can occur in newborns 3 daysPerinatal strokes, which can occur in newborns 3 days
after delivery can cause cerebral palsy.after delivery can cause cerebral palsy.
-cerebral palsy limits functions by causing uncontrollable-cerebral palsy limits functions by causing uncontrollable
spasms, rather than complete paralysis.spasms, rather than complete paralysis.
Another cause is head injuries, that can either
deprive the brain of blood or by affecting the
blood vessels and causing swelling.
-If a person has an injury to the right side of
their brain then the left side of the body will be
paralyzed and vice versa.
It is hard to prevent strokes or cerebral palsy
from occurring in infants, but good prenatal
care can help. Diabetes, hypertension and
high cholesterol makes a person a more likely
to experience a stroke. Being obese, a smoker
and alcoholic will increase your chances as
Encephalitis is the inflammation of the brain dueEncephalitis is the inflammation of the brain due
to disease factors such as rabies, mumps,to disease factors such as rabies, mumps,
herpes simplex 1, chicken pox, influenza,herpes simplex 1, chicken pox, influenza,
measles, west nile virus and small pox.measles, west nile virus and small pox.
It occurs in 1 out of every 200,000 people in theIt occurs in 1 out of every 200,000 people in the
People who are most susceptible are children,People who are most susceptible are children,
elderly, and people who have a weakenedelderly, and people who have a weakened
immune system.immune system.
Primary encephalitis- direct viral infection of thePrimary encephalitis- direct viral infection of the
brain and spinal cordbrain and spinal cord
Secondary encephalitis- infection occursSecondary encephalitis- infection occurs
elsewhere in your body and travels to your brain.elsewhere in your body and travels to your brain.
-acute encephalitis is most common in infants--acute encephalitis is most common in infants-
directly affects brain cells.directly affects brain cells.
-parainfectious encephalitis- most common in-parainfectious encephalitis- most common in
adults- The brain and spinal cord becomeadults- The brain and spinal cord become
inflamed within 1-2 weeks after contracting ainflamed within 1-2 weeks after contracting a
viral or bacterial infection.viral or bacterial infection.
Herpes simplex 1 virus is very common cause of viral encephalitis. ItHerpes simplex 1 virus is very common cause of viral encephalitis. It
tends to erupt rapidly causing seizures, mental health changes, andtends to erupt rapidly causing seizures, mental health changes, and
can even lead to coma or death.can even lead to coma or death.
-- It occurs when the virus travels to the brain rather than to the skinIt occurs when the virus travels to the brain rather than to the skin
where it usually produces a cold sore.where it usually produces a cold sore.
Arbovirus encephalitis is another form of viral encephalitis. It isArbovirus encephalitis is another form of viral encephalitis. It is
caused by various viruses that are carried by Arthropods likecaused by various viruses that are carried by Arthropods like
mosquitoes and Arachnids like ticks. This infection is seasonalmosquitoes and Arachnids like ticks. This infection is seasonal
occurring mainly in the summer and early fall.occurring mainly in the summer and early fall.
In certain cases bacterial, fungal, parasitic or ricketts infectionsIn certain cases bacterial, fungal, parasitic or ricketts infections
cause encephalitis. Cancer or exposure to certain toxins can causecause encephalitis. Cancer or exposure to certain toxins can cause
it as well.it as well.
Symptoms to look for…Symptoms to look for…
Nausea and vomitingNausea and vomiting
Stiff neckStiff neck
Confusion and disorientationConfusion and disorientation
Problems with speechProblems with speech
Personality changesPersonality changes
Memory lossMemory loss
Early recognition is lifeEarly recognition is life
The best way to avoidThe best way to avoid
encephalitis is to prevent theencephalitis is to prevent the
viruses that cause it.viruses that cause it.