Age-Associated Memory Impairment and Cognitive Decline (AAMCD)
Age-associated memory impairment and cognitive decline (AAMCD) describes the mild forgetfulness and decreased cognitive function that are considered part of “normal” aging. AAMCD differs from dementia and other more severe forms of cognitive decline in that it has no impact on daily functioning.
AAMCD is a term used to describe the decline in cognitive function that accompanies normal aging. It is different from pathologic types of cognitive decline – such as Alzheimer’s disease – in that it does not reduce quality of life.
People with AAMCD experience a decrease in fluid intelligence (the ability to solve new problems without prior knowledge), such as processing speed or working memory, but no changes in crystallized intelligence (skills and abilities learned over time), such as vocabulary or historical information. The symptoms are mild and often self-reported.
Because AAMCD is a normal part of aging, there are no standard diagnostic criteria or blood tests. A full clinical evaluation is required to rule out other causes of cognitive symptoms, such as dementia or mild cognitive impairment (MCI). During an examination, a cognitive assessment tool such as the Clock Drawing Test (CDT), Mini-Mental State Examination (MMSE), or Montreal Cognitive Assessment (MoCA) may also be used.
Medication is not required for AAMCD because it is not a pathological condition. If symptoms start to interfere with activities of daily living, such as bathing, getting dressed, and eating, it is best to seek further evaluation by a healthcare provider for more serious causes of cognitive decline, such as Parkinson's disease and Alzheimer's disease.
A variety of dietary patterns have been studied for AAMCD. The Mediterranean, Dietary Approaches to Stop Hypertension (DASH), and Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND) diets have the strongest evidence for maintaining cognitive function. Increased intake of specific foods, such as berries, fish, and extra virgin olive oil may be protective against cognitive decline.
The exact cause of AAMCD is unknown. One hypothesis is that the decline in cognitive function is related to reduced brain matter, specifically white matter. After the age of 70, there is a pronounced reduction in white matter volume. Other potential mechanisms that may play a role in the development of AAMCD are mitochondrial dysfunction, neurotransmitter alterations, chronic inflammation, high levels of stress-related corticosteroids, high blood pressure, vascular changes associated with aging, and oxidative stress.