Toward understanding age-related memory loss in late adulthood

Background: While laboratory tests indicate that older adults typically per form more poorly than do younger adults on many types of memory tasks, the question arises as to whether, or to what extent, it is valid to attribute these differences to ageing per se or to some variable or class of variable s that intervene between age and remembering. Objective: The purpose of thi s review is to present three current views that might explain the relations hip between age and remembering, They can be construed as variants on resou rce theories and include: the processing speed hypothesis, the executive fu nction hypothesis, and the common cause hypothesis. Methods: The review sam ples results pertinent to these hypotheses that derive from behavioural res earch. Studies involving various imaging techniques were considered beyond the scope of the review. Results:The balance of research strongly implicate s reductions in the speed of information processing as a fundamental contri butor to normal age-related memory loss, Nonetheless there are circumstance s where other mechanisms, such as working memory, executive function, and s ensory processes, are important, Conclusion: Despite the phenomenological a nd empirical reality of age-related memory loss and the breadth of attempts to explain Ft, much work remains to be done to understand why it occurs, C ontemporary debates about the nature and means of identifying shared and un ique effects promise to shape future directions for research on memory agin g.