Mild memory loss or Mild Cognitive Impairment (MCI) has distinct characteristics including:
When Does Memory Loss Become a Concern?
- Memory problems that usually do not interfere with the activities of daily living
- Memory problems that are not easily identified by other people (A person experiencing AD-related mild memory loss often uses reminders and other tactics to offset memory difficulties)
- Memory decline in mild cognitive impairment is often a slow process that spans several years
Typical Age-Related Changes
Making a bad decision once in a while
Missing a monthly payment
Forgetting which day it is and remembering later
Sometimes forgetting which word to use
Losing things from time to time
Signs of Alzheimer's/Dementia
Poor judgment and decision-making
Inability to manage a budget
Losing track of the date or the season
Difficulty having a conversation
Misplacing things and being unable to retrace steps to find them
Types of Brain Disorders
Alzheimer’s disease (AD) is a neurodegenerative disorder currently affecting approximately 5 million individuals in the United States. This disorder is characterized by the accumulation of plaques and tangles in the brain. The neuropathology typically begins in the entorhinal cortex of the hippocampus. Since this area is critical for memory, early memory impairment is the leading clinical symptom. As the disease spreads to other portions of the brain, other cognitive functions become disturbed.
Current treatments for AD include the use of cholinesterase inhibitors and memantine, an N-methyl D-aspartate (NMDA) antagonist. While these drugs are capable of producing drug placebo differences in treated populations, neither class of agents has been demonstrated to either slow the rate of decline or prevent the progression of the disease.
In dementing illnesses, the biological changes occur in the brains of patients long before the appearance of symptoms. The definition of mild cognitive impairment (MCI) was developed as an attempt to recognize Alzheimer’s disease (AD) in its very earliest clinical expression in an individual who is destined to develop a progressive dementia at a later point in time. Interventions might then be developed to improve the memory impairment or to delay further deterioration to dementia.
Dementia is a general term for loss of memory and other mental abilities severe enough to interfere with daily life. Physical changes in the brain causes the dementia. Alzheimer’s disease is the most common type of dementia, accounting for 50 to 70 percent of cases. Other causes of dementia include vascular dementia, mild cognitive impairment, mixed dementia, dementia with Lewy bodies, Parkinson’s disease, frontotemporal dementia, Creutzfeldt-Jakob disease, normal pressure hydrocephalus, Huntington’s disease, and Wernicke-Korsakoff syndrome.
Vascular dementia is widely considered the second most common type of dementia. It develops there is impaired blood flow to parts of the brain, which deprives cells of food and oxygen. The diagnosis may be clearest when symptoms appear soon after a single major stroke blocks a large blood vessel and disrupts the blood supply to a significant portion of the brain. This situation is sometimes called “post-stroke dementia.” There is also a form in which a series of very small strokes, or infarcts, block small blood vessels. Individually, these strokes do not cause major symptoms, but over time, their combined effects become noticeable. This type used to be called “multi-infarct dementia.”
Mixed dementia is a condition in which AD and vascular dementia occur at the same time. Many experts believe mixed dementia occurs more often than was previously realized, and that it has become increasingly common in advanced age. This belief is based on brain autopsies showing up to 45 percent of people with dementia having signs of both Alzheimer’s and vascular disease.
The concept of mixed dementia is clinically important because the combination of the two diseases may have a greater impact on the brain than either by itself.
Frontotemporal dementia (FTD) is a rare disorder that affects the front (frontal lobes) and the sides (temporal lobes) of the brain. Since these regions often, but not always, shrink, brain imaging can be useful in diagnosis. There is no specific abnormality associated with all cases of FTD. In one type called Pick’s disease, there are abnormal microscopic deposits called Pick bodies, but these are not always present.
Dementia with Lewy bodies is characterized by abnormal deposits of a protein called alpha-synuclein that form inside the brain’s nerve cells. These deposits are called “Lewy bodies” after the scientist who first described them. Lewy bodies have been found in several brain disorders, including dementia with Lewy bodies, Parkinson’s disease, and some cases of Alzheimer’s.
Parkinson’s disease begins by affecting movement, resulting in tremors and shakiness, stiffness, difficulty with walking and muscle control, lack of facial expression and impaired speech. Parkinson’s is another disease in which Lewy bodies are found in the brain. Many individuals with Parkinson’s develop dementia in later stages of the disease.
Creutzfeldt-Jakob disease (CJD) is a rare, rapidly fatal disorder affecting about 1 out of 1 million people per year worldwide. It usually affects individuals older than 60. CJD is one of the prion diseases that occurs when a prion protein, which is present throughout the brain, begins to assume an abnormal three-dimensional shape. This shape gradually triggers the protein throughout the brain to fold into the same abnormal shape, leading to increasing damage and destruction of brain cells. Recently, “variant Creutzfeldt-Jakob disease” was identified as the human disorder believed to be caused by eating meat from cattle affected by “mad cow disease,” and it tends to occur in much younger individuals, in some cases as early as their teens.
Normal pressure hydrocephalus (NPH) is another rare disorder in which fluid surrounding the brain and spinal cord is unable to drain normally. The fluid builds up, enlarging the ventricles (fluid-filled chambers) inside the brain. As the chambers expand, they can compress and damage nearby tissue. The “normal pressure” refers to the fact that the spinal fluid pressure often, but not always, falls within the normal range on a spinal tap.
Huntington’s disease is a fatal brain disorder caused by inherited changes in a single gene. These changes lead to destruction of nerve cells in certain brain regions. Scientists identified the gene in 1993. Anyone with a parent with Huntington’s has a 50 percent chance of inheriting the gene, and everyone who inherits it will eventually develop the disorder. In about 1 to 3 percent of cases, no history of the disease can be found in other family members.
Wernicke-Korsakoff syndrome is a two-stage brain disorder caused by a deficiency of thiamine (Vitamin B-1). Thiamine helps brain cells produce energy from sugar. When levels of the vitamin are too low, cells are unable to generate enough energy to function properly.
Wernicke encephalopathy is the first acute phase, and Korsakoff psychosis is the long-lasting, chronic stage. The most common cause is alcoholism, but the syndrome can also be associated with AIDS, cancers that have spread through the body, very high levels of thyroid hormone, and certain other conditions.