Nervous System Diseases

Question 1

Multiple Sclerosis

Answer 1

• Literally, “many hardenings”
• MS is a disease of unknown cause that manifests as multiple hard plaques of degeneration of the insulting layer of nerve fibers in the central nervous system
• The loss of insulation allows “short circuiting” of nerve impulses
• Depending on where the degeneration occurs, patients may suffer paralysis, sensory disturbances, or blindness

Question 2

Cerebrovascular accident (CVA)

Answer 2

• Fancy name for stroke
• A blood vessel in the brain may burst causing internal bleeding
• Or, a clot may arise in a brain blood vessel (a thrombus)
• Or, arise elsewhere (embolus) and travel to get stuck in a brain vessel which then deprives brain tissue of oxygen
• Depending on the area of the brain involved, the patient may suffer paralysis, loss of speech, or loss of vision

Question 3

Transient Ischemic Attack (TIA)

Answer 3

• Ischemia = “Not quite enough blood”
• A short period of insufficient blood supply to the brain can have the same signs and symptoms as a stroke such as weakness in an arm, a partial loss of vision, but the problem lasts less than 24 hours
• People who get TIA’s are at increased risk of having a stroke in the future

Question 4

Epilepsy

Answer 4

• Greek word for “seizure”
• Also known as, Convulsions
• Seizures may have many causes and not all seizures are epilepsy
• High fevers in young children may trigger seizures which are short in duration, easily controlled, and typically have no permanent aftereffects
• Epilepsy is a specific condition which may occur at any age, seizures are more intense, longer lasting in duration, and recur with some frequency
• May be controlled with medication, or if unresponsive to drugs, may require surgery

Question 5

Aphasia

Answer 5

• Loss of speech
• Speech centers are located on the left side of the brain in a majority of people
• If someone suffers a stroke (CVA), or traumatic brain injury, and it involves the left side of the brain, they may suffer speech impediments that vary over a spectrum of problems from difficulty in finding the right word, speaking slowly and with difficulty, or complete loss of speech
• There are two speech centers: Motor Speech Area and the Receptive or Sensory Speech Area
• Motor Speech Area = Injury described above, the area that of the brain that produces language by integrating thoughts of speech with the movements of the larynx, lips, and tongue
• Receptive or Sensory Speech Area = Enables us to understand speech
• Injury to the latter results in still fluent speech, but the individual does not understand what they are hearing