TYPES OF DEMENTIA
Dementia is an overall term for diseases and conditions characterized by a decline in memory, language, problem-solving, and other thinking skills that affect a person's ability to perform everyday activities. Memory loss is an example but Dementia is more than just loss of memory. It is brain failure.
Alzheimer's is the most common cause of dementia, a general term for memory loss and other cognitive abilities serious enough to interfere with daily life. Alzheimer's disease accounts for 60-80% of dementia cases.
Most experts estimate that Lewy body dementia is the third most common cause of dementia after Alzheimer's disease and vascular dementia, accounting for 5 to 10 percent of cases.
The brain changes caused by Parkinson’s disease begin in a region that plays a key role in movement, leading to early symptoms that include tremors and shakiness, muscle stiffness, a shuffling step, stooped posture, difficulty initiating movement and lack of facial expression.
Inadequate blood flow can damage and eventually kill cells anywhere in the
body, but the brain is especially vulnerable.
Creutzfeldt-Jakob disease is rare, occurring in about one in 1 million people annually worldwide. Creutzfeldt-Jakob disease causes a type of dementia that gets worse unusually fast. More common causes of dementia, such as Alzheimer's, Lewy body dementia and frontotemporal dementia, typically progress more slowly.
Huntington's disease is a progressive brain disorder caused by a single defective gene on chromosome 4 — one of the 23 human chromosomes that carry a person’s entire genetic code. This defect is "dominant," meaning that anyone who inherits it from a parent with Huntington's will eventually develop the disease.
Normal pressure hydrocephalus is a brain disorder in which excess cerebrospinal fluid accumulates in the brain’s ventricles, which are fluid-filled chambers. Normal pressure hydrocephalus is called "normal pressure" because despite the excess fluid, CSF pressure as measured during a spinal tap is often normal. As brain ventricles enlarge with the excess CSF, they can disrupt and damage nearby brain tissue, leading to difficulty walking, problems with thinking and reasoning, and loss of bladder control.
Scientists don’t know exactly how many people have Korsakoff syndrome. It’s widely considered less common than Alzheimer’s disease, vascular dementia, frontotemporal dementia (FTD) or Lewy body dementia (LBD). Like more common types of dementia, it may be underdiagnosed. Korsakoff syndrome is most commonly caused by alcohol misuse, but can also be associated with AIDS, cancers that have spread throughout the body, chronic infections, poor nutrition and certain other conditions.
Frontotemporal dementia used to be called Pick's disease after Arnold Pick, M.D., a physician who in 1892 first described a patient with distinct symptoms affecting language. Behavior variant frontotemporal dementia (bvFTD) is characterized by prominent changes in personality and behavior. The nerve cell loss is most prominent in areas that control conduct, judgment, empathy and foresight, among other abilities.