2. Multiple Sclerosis (MS)  Progressive destruction of myelin sheaths of neurons in the CNS  Affects females ~2x more than males  Myelin sheaths deteriorate into hardened plaques  Slows & short-circuits conduction of nerve impulses  First symptoms: weakness or heaviness of muscles, abnormal sensation, double vision  Autoimmune disease (body’s own immune system attacks)

3. Epilepsy  Short, recurrent, periodic attacks of motor, sensory, or psychological malfunction  Attacks are called epileptic seizures  1% of world’s population  Initiated by abnormal electrical discharges  Lights, noise, or smells may be sensed when the eyes/ears/nose have not been stimulated  Muscles of person having the seizure may contract involuntarily  Partial seizures begin in a small focus on one side of brain and produce milder symptoms  Generalized seizures involve larger areas on both sides of brain, loss of consciousness

4. Epilepsy, cont.  Causes: brain damage at birth, metabolic disturbances, infections, toxins, low blood pressure, head injuries, tumors. Most have no demonstrable cause  Most can be eliminated or alleviated by antiepileptic drugs

5. Spinal Cord injury  Spinal cord injuries usually result fro trauma (car accidents/falls/sports/violence)  Paralysis may result  Monoplegia – paralysis of one limb only  Diplegia – paralysis of both upper limbs or both lower limbs  Paraplegia – paralysis of both lower limbs  Quadriplegia – paralysis of all four limbs

6. Shingles  Virus that also causes chicken pox (herpes zoster) retreats to nerves near the spinal cord  If the virus is reactivated it travels to the skin  Results in pain, discoloration, blisters

7. Shingles

8. Stroke  “Cerebrovascular Accident”  500,000 people per year in the US  Characterized by abrupt onset of symptoms such as paralysis or loss of sensation that arise from destruction of brain tissues  Often causes by hemorrhage from a blood vessel in the pia mater or brain or blood clots or plaques that block blood flow  Risk factors include high blood pressure, high blood cholesterol, heart disease, smoking, obesity, and excessive alcohol intake

9. Stroke  See “My Stroke of Insight” TED talk