Diseases of the nervous system include stroke, epilepsy, Parkinson’s disease and Alzheimer’s disease, according to WebMD. A stroke occurs from bleeding or a rupture of a blood vessel supplying blood to the brain, while epilepsy is a seizure disorder that affects the electrical activity in the brain, explains Healthline. Alzheimer's disease is a mental and memory disorder, causing difficulty remembering and confusion, notes Mayo Clinic. Parkinson's disease is an incurable disorder that develops gradually, affecting movement.
Stroke may occur from a leaking or blocked artery in the brain, damaging tissues and brain cells, notes Healthline. Symptoms include difficulty speaking, loss of balance, paralysis and severe headache. Risk factors include inactivity, excessive alcohol drinking and eating diets high in saturated fats, cholesterol and salt.
As of 2016, the cause of epilepsy is unclear in some people, reports Healthline. Risk factors include brain tumor, traumatic brain injury, brain infection and Alzheimer’s disease.
Conditions such as mood swings, depression, irritability and delusions may accompany Alzheimer’s disease, states Mayo Clinic. Risk factors include obesity, smoking, high blood pressure and sedentary lifestyle.
Parkinson’s disease occurs from the gradual breakdown of nerve cells called neurons in the brain, according to Mayo Clinic. Parkinson’s disease is more common in men than in women, and risk factors increase with age, heredity and exposure to pesticides and herbicides.