Definitions and Symptoms
Mild cognitive impairment
Mild cognitive impairment is a transition stage between normal aging and the more serious problems of dementia caused by Alzheimer's disease and related conditions. The most common variety of mild cognitive impairment – termed amnestic mild cognitive impairment - is associated with the tendency to forget upcoming appointments and details of recent events and conversations, and such individuals tend to repeat questions or statements. Many people with mild cognitive impairment eventually develop Alzheimer's disease, although some remain stable and others even return to normal. Those with other varieties of mild cognitive impairment tend to develop Lewy body dementia, vascular dementia, or frontotemporal dementia. The core features of mild cognitive impairment are:
Dementia refers to a set of symptoms, not the disease itself. These symptoms might include language difficulty, loss of recent memory or poor judgment. In other words, when an individual is said to have dementia, they are exhibiting certain symptoms that causes a loss of independence. With a thorough screening including blood tests, a mental status evaluation, neuropsychological testing, and a brain scan, doctors can accurately diagnose the cause of the dementia symptoms. Although Alzheimer's disease accounts for 60-70 percent of cases of dementia, other disorders that cause dementia include: Vascular dementia, Parkinson's disease with dementia, dementia with Lewy Bodies and Frontotemporal dementia.
Alzheimer's disease is the most common cause of dementia, which is the loss of intellectual and social abilities severe enough to interfere with daily functioning. Dementia occurs in people with Alzheimer's disease because healthy brain tissue degenerates, causing a steady decline in memory and other mental abilities. Most people with Alzheimer's share certain signs and symptoms of the disease. These may include:
Lewy body dementia
Lewy body dementia shares characteristics with both Alzheimer's disease and Parkinson's disease. Like Alzheimer's, it causes confusion. Like Parkinson's, it can result in rigid muscles, slowed movement and tremors. The most striking symptoms of Lewy body dementia may be its visual hallucinations, which can be one of the first signs of the disorder. Lewy body dementia signs and symptoms may include:
Frontotemporal dementia (FTD) is an umbrella term for a diverse group of rare disorders that primarily affect the frontal and temporal lobes of the brain — the areas generally associated with personality and behavior. Frontotemporal dementia tends to occur at a younger age than does Alzheimer's disease, typically between the ages of 40 and 70. Frontotemporal dementia signs and symptoms include behavioral and personality changes that may include:
Primary Progressive Aphasia
Primary Progressive Aphasia (PPA) is characterized by an increasing difficulty in using and understanding written and spoken language. People with another subtype, semantic dementia, utter grammatically correct speech that has no relevance to the conversation at hand.
Corticobasal degeneration (CBD) is a degenerative disorder of the brain in which nerve cells die over time, causing a progressive decline in the ability to move one or both sides of the body. Symptoms include arm or leg incoordination, arm or leg stiffness, tremor, gait unsteadiness, speech difficulty and problems with language (word finding, sentence structuring, comprehension, reading and writing).
Progressive Supranuclear Palsy
Progressive Supranuclear Palsy (PSP) is a degenerative disorder of the brain in which nerve cells die over time, causing a progressive decline in the ability to maintain balance and move the eyes. Symptoms include neck, arm or leg stiffness, gait unsteadiness, frequent falls, Parkinson’s-like symptoms, and vision problems.
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