Rose T. Zacks

Bio: Rose T. Zacks is an academic researcher from Michigan State University. The author has contributed to research in topics: Short-term memory & Working memory. The author has an hindex of 5, co-authored 5 publications receiving 5123 citations.

Working Memory, Comprehension, and Aging: A Review and a New View

Abstract: Publisher Summary This chapter discusses the theoretical and empirical literature that addresses aging and discourse comprehension. A series of five studies guided by a particular working memory viewpoint regarding the formation of inferences during discourse processing is described in the chapter. Compensatory strategies may be used with different degrees of likelihood across the life span largely as a function of efficiency with which inhibitory mechanisms function because these largely determine the facility with which memory can be searched. The consequences for discourse comprehension in particular may be profound because the establishment of a coherent representation of a message hinges on the timely retrieval of information necessary to establish coreference among certain critical ideas. Discourse comprehension is an ideal domain for assessing limited capacity frameworks because most models of discourse processing assume that multiple components, demanding substantially different levels of cognitive resources, are involved. For example, access to a lexical representation from either a visual array or an auditory message is virtually capacity free.

Studies of directed forgetting in older adults.

Abstract: Younger and older adults were compared in 4 directed forgetting experiments. These varied in the use of categorized versus unrelated word lists and in the use of item by item versus blocked remember-forget cueing procedures. Consistent with L. Hasher and R. T. Zacks's (1988) hypothesis of impaired inhibitory mechanisms in older adults, a variety of findings indicated that this age group is less able than yoimger adults to suppress the processing and retrieval of items designated as to be forgotten (TBF). Specifically, in comparison with younger adults, older adults produced more TBF word intrusions on an immediate recall test (Experiments 1A and 1B), took longer to reject TBF items (relative to a neutral baseline) on an immediate recognition test (Experiment 3), and recalled (Experiments 1A, 1B, and 2) and recognized (Experiments 1B and 2) relatively more TBF items on delayed retention tests in which all studied items were designated as targets. In this article, we present four experiments comparing the performance of younger and older adults on directed forgetting tasks. In this type of task (e.g., see Bjork, 1989), participants are presented items to study, some of which they are told to remember and others of which they are told to forget. Because the cueing as to which items are to be remembered (TBR items) and which are to be forgotten (TBF items) occurs after the items have been presented for study, participants must pay some attention to each item as it is presented. Thus, the directed forgetting paradigm investigates the ability to forget some inputs that one has recently attended to while at the same time remembering others presented in the same context and near the same time. To the degree that one is successful at this task, as younger adults generally are, the following trends are seen: The presence of TBF items on a list does not reduce recall or recognition of TBR items; there are few intrusions of TBF items when participants are asked to report only TBR items; and performance on TBF items is relatively poor when, on a later retention test, participants are asked to report TBF as well as TBR items.

The unity and diversity of executive functions and their contributions to complex "Frontal Lobe" tasks: a latent variable analysis.

Abstract: This individual differences study examined the separability of three often postulated executive functions-mental set shifting ("Shifting"), information updating and monitoring ("Updating"), and inhibition of prepotent responses ("Inhibition")-and their roles in complex "frontal lobe" or "executive" tasks. One hundred thirty-seven college students performed a set of relatively simple experimental tasks that are considered to predominantly tap each target executive function as well as a set of frequently used executive tasks: the Wisconsin Card Sorting Test (WCST), Tower of Hanoi (TOH), random number generation (RNG), operation span, and dual tasking. Confirmatory factor analysis indicated that the three target executive functions are moderately correlated with one another, but are clearly separable. Moreover, structural equation modeling suggested that the three functions contribute differentially to performance on complex executive tasks. Specifically, WCST performance was related most strongly to Shifting, TOH to Inhibition, RNG to Inhibition and Updating, and operation span to Updating. Dual task performance was not related to any of the three target functions. These results suggest that it is important to recognize both the unity and diversity of executive functions and that latent variable analysis is a useful approach to studying the organization and roles of executive functions.

The processing-speed theory of adult age differences in cognition.

Abstract: A theory is proposed to account for some of the age-related differences reported in measures of Type A or fluid cognition. The central hypothesis in the theory is that increased age in adulthood is associated with a decrease in the speed with which many processing operations can be executed and that this reduction in speed leads to impairments in cognitive functioning because of what are termed the limited time mechanism and the simultaneity mechanism. That is, cognitive performance is degraded when processing is slow because relevant operations cannot be successfully executed (limited time) and because the products of early processing may no longer be available when later processing is complete (simultaneity). Several types of evidence, such as the discovery of considerable shared age-related variance across various measures of speed and large attenuation of the age-related influences on cognitive measures after statistical control of measures of speed, are consistent with this theory.

Working memory,short-term memory, and general fluid intellegence : A latent-variable approach

Abstract: A study was conducted in which 133 participants performed 11 memory tasks (some thought to reflect working memory and some thought to reflect short-term memory), 2 tests of general fluid intelligence, and the Verbal and Quantitative Scholastic Aptitude Tests. Structural equation modeling suggested that short-term and working memories reflect separate but highly related constructs and that many of the tasks used in the literature as working memory tasks reflect a common construct. Working memory shows a strong connection to fluid intelligence, but short-term memory does not. A theory of working memory capacity and general fluid intelligence is proposed: The authors argue that working memory capacity and fluid intelligence reflect the ability to keep a representation active, particularly in the face of interference and distraction. The authors also discuss the relationship of this capability to controlled attention, and the functions of the prefrontal cortex.

Working memory, short-term memory, and general fluid intelligence: A latent-variable approach.

Abstract: A study was conducted in which 133 participants performed 11 memory tasks (some thought to reflect working memory and some thought to reflect short-term memory), 2 tests of general fluid intelligence, and the Verbal and Quantitative Scholastic Aptitude Tests. Structural equation modeling suggested that short-term and working memories reflect separate but highly related constructs and that many of the tasks used in the literature as working memory tasks reflect a common construct. Working memory shows a strong connection to fluid intelligence, but short-term memory does not. A theory of working memory capacity and general fluid intelligence is proposed: The authors argue that working memory capacity and fluid intelligence reflect the ability to keep a representation active, particularly in the face of interference and distraction. The authors also discuss the relationship of this capability to controlled attention, and the functions of the prefrontal cortex.

Exploring the Central Executive

Abstract: The central executive component of working memory is a poorly specified and very powerful system that could be criticized as little more than a homunculus. A research strategy is outlined that attempts to specify and analyse its component functions and is illustrated with four lines of research. The first concerns the study of the capacity to coordinate performance on two separate tasks. A second involves the capacity to switch retrieval strategies as reflected in random generation. The capacity to attend selectively to one stimulus and inhibit the disrupting effect of others comprises the third line of research, and the fourth involves the capacity to hold and manipulate information in long-term memory, as reflected in measures of working memory span. It is suggested that this multifaceted approach is a fruitful one that leaves open the question of whether it will ultimately prove more appropriate to regard the executive as a unified system with multiple functions, or simply as an agglomeration of indepe...