The Decline of Memory with Aging is Complex
Memory is not a straightforward function of the brain. There are many different aspects to storing and recalling memories of various types, and all decline in different ways with advancing age, a reflection of the influence of damage on quite different structures and mechanisms in brain tissue.
Researchers conclude that the memory of older adults is not as deficient as has been thought until now. Elderly people remember fewer specific details than younger people and, in general, both groups retain concrete information about events experienced better than abstract information. The main difference is to be found in the capacity to remember more distant facts: youngsters remember them better. "The highly widespread belief that memory deteriorates as one approaches old age is not completely true. Various pieces of neuro-psychological research and other studies show that cognitive loss starts at the age of 20 but that we hardly notice it because we have sufficient capacity to handle the needs of everyday life.This loss is more perceptible between 45 and 49 and, in general, after the age of 75, approximately."The deterioration does not tend to be either uniform or general: It takes place in certain memory types more than in others. In old age, deterioration appears in episodic memory but not in semantic memory. This type of memory (semantic) and procedural memory are maintained (in some cases they even improve) whereas episodic memory in which detailed memories are retained is reduced. Procedural memory is the one to do with 'skills', the one we need to 'do things' (to drive, for example). In general, it is maintained during old age. Semantic memory, on the other hand, is related to language, to the meaning of concepts and to repetitive facts. Finally, episodic memory preserves the facts (episodes) of the past in our personal life, and it is more specific in terms of time and space.
An individual, both an adult and a young person, has the capacity to remember information relating to facts in his/her private life in detail. The main difference between older adults and younger adults is as follows: the younger ones remember more episodic details. This research shows, however, that this difference only occurred in older recollections, such as of the previous year. No appreciable differences were found in the recollections of the previous month and the previous week, and the older adults were just as capable as the younger adults in providing episodic details relating to the facts.
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