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Chapter 12 - Alterations in Executive Functions with Aging
- Edited by Kenneth M. Heilman, University of Florida, Stephen E. Nadeau, University of Florida
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- Book:
- Cognitive Changes and the Aging Brain
- Published online:
- 30 November 2019
- Print publication:
- 05 December 2019, pp 168-187
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Summary
It is frequently reported that processing speed slows and executive functions (EFs) become less effective in the course of healthy aging. This chapter highlights research supporting these claims in three areas of investigation: cognitive aging research, the neuropsychological perspective, and studies evaluating the association of EF with structural and functional imaging measures. Several themes emerge in this review. For example, diminished processing speed with aging appears to reflect aging-related changes in the anterior cingulate/superior medial frontal cortex, as well as perceptuomotor slowing. The definition of EF varies between different publications and there is a need for more precise operational definitions. There is also a need to decompose EFs into their component processes. Impairments of EF are strongly related to damage in prefrontal regions, but disorders of EF also occur with injury to nonfrontal regions, indicating that complex networks are involved in EF. Additionally, domain-specific changes beyond the changes in EF are important considerations in network analyses. We propose a method to advance future research on EF by using focal frontal lesion studies and neural network principles as frameworks to expand our understanding of aging-related changes in EF and processing speed.
26 - Levels of Processing in Human Memory
- from Section B - Learning and Memory
- Edited by Robert J. Sternberg, Cornell University, New York, Susan T. Fiske, Princeton University, New Jersey, Donald J. Foss, University of Houston
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- Book:
- Scientists Making a Difference
- Published online:
- 05 August 2016
- Print publication:
- 11 August 2016, pp 128-131
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Summary
Throughout my professional career as a cognitive psychologist, I have been interested in the topics of memory, attention, perception, and thinking – how best to characterize them, how they relate to each other, and how they change over a person's lifespan. In everyday life, these mental activities are usually considered to be rather different from each other – remembering meeting someone a month ago seems different from seeing the person in front of you – and this separation is often echoed in psychology textbooks, in which perception, memory, and decision-making are treated in different chapters. Much of the current thinking in cognitive psychology has reacted against this commonsense view, however, suggesting instead that these areas of study are better regarded as closely related and interacting aspects of one general processing system.
This latter position was one starting point for the formulation of the levels of processing (LOP) framework for memory research proposed by Robert Lockhart and myself in 1972. The LOP article with Lockhart, plus a later empirical article with Endel Tulving in 1975, are my most-cited pieces of published research, and may therefore be regarded as my best-known scientific contributions to cognitive psychology. Additionally, the general ideas in which the LOP framework was embedded – for example, that remembering should be regarded as an activity of mind rather than a collection of structural “memory traces” waiting to be revived – have always been central to my thinking about memory. Thus, the LOP paper and its spinoffs have been the starting point for much of the work that my lab has produced over the years.
In the 1960s, ideas about learning and memory were changing from the belief that the formation of associations between two mental events was the crucial element, to concepts derived from information-processing theories. From this latter point of view, the brain/mind was regarded as a highly sophisticated computer, processing sensory information from the environment, performing computations on that information, and finally translating the products into relevant actions. To accomplish these operations efficiently, the proposed system needed a variety of memory stores, holding information of different qualitative types either temporarily, while it was processed, or relatively permanently, in the case of learned knowledge.
10 - Adult age differences in working memory
- Edited by Giuseppe Vallar, Università degli Studi di Milano, Tim Shallice, University of Cambridge
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- Book:
- Neuropsychological Impairments of Short-Term Memory
- Published online:
- 11 May 2010
- Print publication:
- 27 July 1990, pp 247-267
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Summary
Introduction
The notion that some degree of short-term memory impairment is typically found in healthy older people has been current for the last 30 years or so. Welford (1958) surveyed the results of several dual-task experiments and proposed that many of the deficits associated with the normal aging process – in memory, learning, reasoning, and perceptual–motor tasks – may have their basis in the reduced efficiency of short-term memory; in particular, it seemed that both the capacity of this memory store, and its ability to resist the interfering effects of other activities, declined in the course of normal aging. However, by the time that Craik (1977) reviewed the literature on age differences in memory, more techniques to measure short-term (or primary) memory were available, and it appeared that Welford's suggestion was either faulty or too general. Craik pointed out that age differences were minimal in such measures as digit span, the recency effect in free recall, and the slope of the Brown–Peterson function. A possible resolution of the apparent conflict is that age differences do not appear (or are slight) in areas where the task calls for relatively passive storage of some small amount of material and then for its retrieval in much the same form, whereas age differences are substantial when the subject must manipulate the material held, or actively rehearse one set of material while simultaneously perceiving or responding to further material (Craik, 1977).
This latter characterization is very similar to the concept of a “general working memory” as described by Baddeley (1986; this volume, chapter 2).