Memory
Memory is broken down into two types: short term and long term.
Short-term memory, also known as working memory, stores information that you need to remember in the following seconds, minutes or hours. An example would be a telephone message that you are given and must remember until you pass it on.
Long-term memory stores information that your brain retains because it is important to you. Basic information remembered includes names of family and friends, your address, as well as information on how to do certain activities and tasks. Long-term memory can be further divided into explicit, implicit and semantic memory.
- Explicit memories are facts that you made a conscious effort to learn and that you can remember at will, for example, the names of state capitals.
- Implicit memory is information you draw on automatically in order to perform actions such as driving a car or riding a bicycle.
- Semantic memories are facts that are so deeply ingrained they require no effort to recall. An example would be the months of the year.
What is normal aging and memory?
As we age, slight changes occur in our cognition that affect memory. Simple forgetfulness (the "missing keys") and delay or slowing in recalling names, dates, and events can be part of the normal process of aging. Memory has various forms, though, that might be affected differently by aging.
Preserved memory functions
- Remote memory
- Procedural memory (performing tasks)
- Semantic recall (general knowledge)
- Learning new information
- Recalling new information (takes longer to learn something new and to recall it)
- Language ("The words, their pronunciation, and the methods of combining them used and understood by a community") is modestly affected by aging.
- Language comprehension (understanding the rules of language) is preserved, as are vocabulary (semantic memory) and syntax (the way in which words are put together).
- Some modest decline is seen with spontaneous word finding ("tip of the tongue") and verbal fluency (takes longer to "get the words out").
- While verbal intelligence (vocabulary) remains unchanged with aging, the speed of information processing gradually slows (such as problem-solving skills).
- Executive functions (planning, abstracting) remain normal for everyday tasks, but are slowed when faced with novel tasks or divided attention ("multi-tasking").
- A slowing of the speed of cognitive processing and reaction time ("hitting the buzzer") occur with aging.
When is memory not so normal?
Amnesia ("memory loss") is not a part of the normal aging process. While it may take longer to learn new information (for example, names of people) or to recall learned information (for example, names of friends in photos), with a little time and extra effort memory occurs. Some people are more forgetful, but this might be because of health conditions (for example, depression, heart disease, thyroid disease and vitamin deficiencies) or medication effects.
Memory loss is abnormal in people with mild cognitive impairment or dementia (a loss of intellectual functions severe enough to interfere with everyday social or occupational functioning).
Mild cognitive impairment
- Important memory impairments occur without loss of independent functioning.
- Forgetfulness and struggling to perform self-care tasks (for example, taking medications, paying bills) but still able to do so without the direct help of another person.
Memory, language, and cognition are so impaired that self-care tasks can no longer be performed without assistance from another person.
Not-so-normal memory conditions and symptoms:
Mild cognitive impairment
- Aging
- Pre-Alzheimer’s
- Silent "strokes" (infarcts)
- Head injury
- Forgetfulness or amnesia for recent events
- Need to write reminders to do things or else will forget
- Struggles but is able to perform daily chores and tasks
- Sometimes needs a reminder or prompt to remember
Dementia
- Alzheimer’s
- Vascular (stroke)
- Others: Pick’s, hydrocephalus, drugs/alcohol, etc
- Unable to perform complex daily tasks (for example, paying bills, taking medications, shopping, driving)
- Loss of insight or awareness of memory loss
- Poor judgment
- Behavioral symptoms (for example, irritability worrying, anger, agitation, suspiciousness)
Research has shown the following:
- Continued education (college) helps preserve "cognitive reserve" and delays the onset of dementia.
- A healthy diet--one high in antioxidants and olive oil--lowers the risk of dementia.
- Cognitive training (memory training, reasoning training, speed-of-process training) improves cognition.
- Playing board games (chess, checkers, cards) and musical instrument delays the onset of dementia.
- Engaging in social activities slows cognitive decline.
- Reducing cardiovascular risks (for example, treating hypertension) delays the onset of dementia.
Informations obtained from National Institute of Health.