Dementia (dee-MEN-shuh) is a decline in mental ability that usually progresses slowly, causing problems with thinking memory, and judgment. It is most often seen in the elderly and is caused by deterioration in parts of the brain. A person with dementia eventually has difficulty with the activities of everyday living, such as balancing a checkbook, reading and working.


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Why Doesn't Grandpa Recognize Me?

As Jacob sat in the hospital waiting room, he reminisced about this same day last year; Grandpa had taken him to the Baltimore Oriole's home opener to celebrate his eleventh birthday. Since then, his grandfather had experienced a few small strokes, or blockages in the blood vessels that supply oxygen and nutrients to his brain. The resulting loss of oxygen caused damage to parts of Grandpa's brain, and now he could barely talk or make any decisions for himself. Grandpa was 70 years old, but he almost seemed like a little kid.

During today's visit, Grandpa did not seem to know that it was Jacob's twelfth birthday. In fact, Grandpa did not even seem to know who Jacob was. Seeing his grandfather in this state made Jacob very sad and a little bit angry. He did not understand why his grandfather did not recognize him. Grandpa's doctor saw Jacob sitting in the waiting room and knew he was upset. She sat beside him and explained that Grandpa did not recognize people because he had a condition called dementia, which was a result of the brain damage caused by the strokes. She said that only time would tell if Grandpa's condition would improve, but in the meantime Jacob should keep visiting him, talking to him, and including him in special occasions. She told Jacob that even though Grandpa might act differently in many ways, there was still a part of the old Grandpa inside, and that Jacob's presence could still bring enjoyment to him.

What Are the Symptoms of Dementia and
Who Is Affected?

People who develop dementia typically experience changes in personality, frequent confusion, and a lack of energy. Thinking, reasoning, memory, and judgment are often affected, and a person with dementia might also have trouble with language and motor (movement) skills.

Dementia is mostly a disease of the elderly. It is estimated to affect more than 15 percent of people (about 1 in 7) over age 65 but as many as 40 percent of people (2 out of 5) over age 80. It is one of the most common reasons for nursing home admissions in the United States, and it is a condition that many older people fear. When dementia affects young people, it is usually the result of an injury or some other condition that causes brain damage.

What Causes Dementia?

Dementia can result from any damage that interferes with the normal functioning of the brain. This damage may be permanent or temporary, and it can have a variety of causes that are usually classified into three categories:

  1. Structural: a problem with the structure of the brain.
  2. Infectious (in-FEK-shus): a bacterium or virus causes an infection that interferes with brain function.
  3. Metabolic * or toxic: a problem with the substances in the blood that are needed to nourish the brain.

* metabolic (meh-tuh-BALL-ik) pertains to the process in the body (metabolism) that con-verts food into energy and waste products.

Structural causes of dementia

The most common cause of dementia is Alzheimer (ALZ-hy-mer) disease, a condition in which abnormal structures (called plaques and tangles) accumulate in the brain over time and interfere with nerve cell connections. Alzheimer disease leads to a gradually worsening loss of mental abilities, including memory, judgment, and abstract thinking, as well as to changes in personality. This disease usually affects people over age 65, and doctors are not sure of the causes.

Successive strokes are the second most common cause of dementia. Strokes, or blockages in some of the blood vessels that feed the brain, gradually destroy areas of brain tissue that normally are fed by the blocked blood vessels. People who develop this condition often have a history of high blood pressure * and/or diabetes * .

Other structural causes of dementia include:

  • A brain tumor, which is a mass of abnormal cells growing in the brain. As the tumor grows, it presses on certain areas of the brain and causes personality change and problems with thinking, movement, and other functions. Severe or repeated milder head injuries can lead to dementia, also.
  • Parkinson disease is a slowly progressing, degenerative * disorder of the nervous system that leads to shaking, difficulties with movement, and muscle stiffness. About 15 to 20 percent of people who have it also develop dementia. Former Attorney General Janet Reno, boxer Muhammad Ali, and actor Michael J. Fox are three well-known people who have Parkinson disease.
  • Huntington disease is a rare inherited disease in which people in midlife begin having occasional jerks or spasms that are caused by a gradual loss of brain cells. People with Huntington disease eventually develop uncontrolled movements and mental deterioration.

Dementia caused by infectious diseases

People who have Acquired Immunodeficiency Syndrome * (AIDS) sometimes experience dementia because the virus that causes AIDS can infect the brain. Another dementia-causing condition is Creutzfeldt-Jakob Disease (CJD), a very rare, rapidly progressing disease that affects the brain. Doctors are not sure what causes CJD, although in some cases it appears to have been passed from human to human by contaminated surgical instruments. One form of the disease has been found in humans who have eaten beef from a cow that has "mad cow disease". Yet another cause of dementia is viral encephalitis [en-sef-uh-LIGHT-us], an inflammation of the brain that can be caused by certain viruses, particularly those transmitted to humans by the bite of a mosquito.

* high blood pressure, or hypertension, is a condition in which the pressure of the blood in the arteries is above normal. Arteries are the blood vessels that carry blood from the heart through the entire body.

* diabetes (dy-a-BEE-teez) is a condition in which the body is unable to take up and use sugar from the bloodstream normally to produce energy. It is caused by low levels of insulin (the hormone that controls this process) or the inability of the body to respond to insulin normally.

* degenerative (dee-JEN-er-uhtiv) means progressive deterioration. A degenerative disease results in diminished function or impaired structure of a tissue or organ.

* Acquired Immunodeficiency Syndrome, or AIDS, is a viral disease that damages the immune system, leaving a person at high risk for many life-threatening infections.

Metabolic causes of dementia

Having too much or too little of certain substances in the body can damage the brain enough to cause dementia. For example, anoxia (too little oxygen reaching the brain), vitamin B12 deficiency, and hypoglycemia (hy-po-gly-SEE-mee-uh; a lower than normal amount of sugar in the bloodstream) are conditions that can lead to dementia if left untreated. People with severe alcoholism can also develop dementia, due to a condition known as Wernicke-Korsakoff syndrome. This syndrome occurs when a person's body has too little of a vitamin called thiamine, which plays a key role in helping the brain process sugar for energy; over time, a thiamine deficiency can cause men-tal confusion and memory loss. People who are malnourished or do not get enough of certain other nutrients from their diet have also been known to develop Wernicke-Korsakoff syndrome.

Get To Know The Scientists

Many dementia-causing conditions are named after the physicians or scientists who discovered them:

  • Alois Alzheimer was the German physician who published an article on a "new disease of the cortex" (the outermost or "reasoning" portion of the brain) in 1907. The disease is now called Alzheimer disease.
  • James Parkinson was the English physician who published "Essay on the Shaking Palsy" in 1817. This was one of the first articles on the disease now named for him.
  • George Huntington was an American doctor from Ohio whose 1872 paper on hereditary chorea (kor-EE-uh; a condition of uncontrolled, rapid movements) made him famous because of its accurate and complete descriptions of this disease. The condition is now better known as Huntington chorea or Huntington disease.
  • Hans Gerhard Creutzfeldt and Alfons Jakob were two German physicians who, in the 1920s, first described the brain disease now known by their names.
  • Carl Wernicke was a German physician whose 1881 Textbook of Brain Disorders first described a nervous system condition caused by insufficient amounts of a vitamin known as thiamine.
  • Sergei Korsakov was a nineteenth-century Russian psychiatrist who studied and described the connections among alcoholism, nerve inflammation, and mental symptoms.

How Is Dementia Diagnosed and Is It Treatable?

The process of diagnosing dementia usually begins when the person and/or family members begin to notice that the person is experiencing increasing forgetfulness, lapses in memory, or problems with everyday tasks. The doctor may give the patient a mental status test by asking a series of questions that require memory of everyday events or by asking the patient to perform simple tasks like counting backwards. The doctor also will try to determine whether there is some underlying cause of the person's symptoms. Blood tests and scans of the brain can help the doctor see whether there is an imbalance of certain substances in the body or a structural problem in the brain. The doctor also will ask for a complete description of the person's symptoms, his or her family medical history, current medications, and about the presence of any other medical conditions (such as high blood pressure or diabetes).

In most cases, dementia cannot be cured; rather, it is more likely to worsen over time, especially when a progressive disease such as Alzheimer disease or Parkinson disease is the cause. However, in some cases the worsening of dementia can be slowed and sometimes the symptoms can actually improve if the underlying cause can be addressed. For example, controlling blood pressure and quitting smoking can slow or stop progressive dementia associated with blockages in blood vessels within the brain. Stopping excessive alcohol intake or correcting a vitamin deficiency can also help, if that is what is causing the problem.

When a Loved One Has Dementia

Dementia is especially hard on family members and loved ones who remember the person as he or she once was. The loss of memory, increased helplessness, and personality changes can be especially difficult to witness and accept. However, family and friends can play an important role in helping the person deal with dementia. The presence of familiar faces, regular exercise, and maintaining a bright, cheerful, familiar environment have been shown to help people with dementia. Caregivers can also help the person establish a routine, take part in low-stress activities, and get good nutrition and exercise on a regular basis. Large calendars and clocks can help the person keep track of the day and time. Reminders from family, friends, or other caregivers about what is going on, who they are, and where the person is can also be helpful.



Alzheimer's Association, 919 North Michigan Avenue, Suite 1100, Chicago, IL 60611-1676. The Alzheimer's Association is a support organization for people with Alzheimer disease and their families.
Telephone 800-272-3900

The American Geriatrics Society, The Empire State Building, 350 Fifth Avenue, Suite 801, New York, NY 10118. The American Geriatrics Society website features information on dementia and dementia-related conditions.
Telephone 212-308-1414

U.S. National Institute of Neurological Diseases and Stroke (NINDS), Bethesda, MD 20824. NINDS posts fact sheets about dementia and dementia-related conditions at its website; a keyword search for "dementia" calls up a range of information.

Family Caregiver Alliance, 690 Market Street, Suite 600, San Francisco, CA 94104. The Family Caregiver Alliance offers information helpful to people who are caring for loved ones with dementia.
Telephone 415-434-3388

See also
Alzheimer Disease
Brain Chemistry (Neurochemistry)
Brain Injuries

Also read article about Dementia from Wikipedia

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