Alzheimer's disease, which affects more than 5 million Americans, is a brain disorder that over time destroys a person’s memory and ability to learn, reason, make judgments, communicate and perform daily activities. The disease usually begins after age 60, with the risk going up with age. It is estimated that about half of the population 85 and older has Alzheimer’s; therefore, it is not an inevitable part of aging. Rarer forms of the disease can occur earlier in life. The brains of people with Alzheimer’s are characterized by having clumps, called amyloid plaques, and tangled fibers, called neurofibrillary tangles, but what causes them remains an active area of research. Genetics and aspects of aging may play a role in creating the brain changes that most likely cause the disease symptoms. As Alzheimer’s progresses, individuals may experience changes in personality and behavior, including anxiety, suspiciousness, agitation, delusions and hallucinations. Disease course varies with each individual, but the average person lives 8 to 10 years after diagnosis. No cure currently exists for Alzheimer’s and drugs have variable effectiveness, but considerable research about the disease is leading to new approaches to drugs. Effective care and support has been shown to improve the quality of life for people with Alzheimer’s and their caregivers.

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Epilepsy is a central nervous system disorder (neurological disorder) in which nerve cell activity in the brain becomes disrupted, causing seizures or periods of unusual behavior, sensations and sometimes loss of consciousness.

Seizure symptoms can vary widely. Some people with epilepsy simply stare blankly for a few seconds during a seizure, while others repeatedly twitch their arms or legs.

About 1 in 26 people in the United States will develop a seizure disorder. Nearly 10 percent of individuals may have a single unprovoked seizure. However, a single seizure doesn't mean you have epilepsy. At least two unprovoked seizures are generally required for an epilepsy diagnosis.

Even mild seizures may require treatment because they can be dangerous during activities such as driving or swimming. Treatment with medications or sometimes surgery can control seizures for about 80 percent of people with epilepsy. Some children with epilepsy may also outgrow their condition with age.

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Parkinson's disease is a chronic, progressive brain disorder classified as a motor system disorder. It is often diagnosed around age 60, with patients experiencing tremors or trembling, balance difficulties, muscle stiffness, and slowness of movement (also called bradykinesia). Other symptoms may include dementia, depression, anxiety, constipation, urinary difficulties and sleep disturbances, with symptoms worsening over time. There are approximately 1.5 million people in the U.S. living with Parkinson's Disease, with about 60,000 new cases diagnosed each year. Parkinson's appears to result from an interplay of genetic and environmental factors--some with Parkinson's appear to have a gene mutation which increases susceptibility to environmental and other factors. It is not currently possible to predict who will get Parkinson's, or to prevent it. Parkinson's is associated with a loss of brain cells which produce the brain chemical dopamine--this discovery led to the development of an important drug treatment in 1970 called levodopa. Levodopa significantly improves mobility, and enables relatively normal functioning. However, as the disease progresses, larger doses are required. Additionally, levodopa also has severe side effects for some people. As a result, other drugs have been developed to lessen these side effects. Other drugs have been developed to work in conjunction with Levodopa. Targeted surgery may be used as a rare treatment (not cure) for severe Parkinson's disease or for those who do not respond to medications, and may help in alleviating specific symptoms rather than all the symptoms associated with Parkinson's. An alternative treatment to targeted surgery is deep brain stimulation (DBS), which involves implanting an electrode in the brain which emits electrical pulses to stimulate the brain and block brain signals that result in symptoms of Parkinson's. Early results of this treatment look very promising, particularly in relieving tremors. Research continues in other areas to find the cause or causes of Parkinson's disease, better treatments and an eventual cure.

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Tourette Syndrome (TS) is a neurological brain disorder with the age of onset between the ages of 3 and 9. Males are 3 to 4 times more likely to have TS than females. It is diagnosed by the presence of multiple motor and/or vocal tics, classified as simple or complex, which last more than one year. People with TS all have involuntary movements, while only some have vocalizations. Symptoms vary by individual and can range from mild to severe, with most in the mild range. Comorbid or co-occurring conditions may include learning disabilities, attentional problems (ADHD/ADD, impulsiveness and oppositional defiant disorder), and obsessive compulsive behaviors. Research indicates that TS may result from abnormal activity of the neurotransmitter dopamine and its receptors. Other neurotransmitters such as serotonin may also be involved. The majority of people with TS do not require medication, as they are not significantly disabled by it. However, if symptoms interfere with daily functioning, medications may be helpful. These can include clonazepam (Klonopin), clonidine (Catapres), fluphenazine (Prolixin, Permitil), haloperidol (Haldol), pimozide (Orap), and risperidone (Risperdal). Psychotherapy may be beneficial for assisting with coping skills, and some behavior therapies may help in substituting one tic for another more acceptable one.

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