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416
Models of visuospatial and verbal memory across the life span
- Psychology and Aging
, 2002
"... The authors investigated the distinctiveness and interrelationships among visuospatial and verbal memory processes in short-term, working, and long-term memories in 345 adults. Beginning in the 20s, a continuous, regular decline occurs for processing-intensive tasks (e.g., speed of processing, worki ..."
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Cited by 132 (9 self)
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The authors investigated the distinctiveness and interrelationships among visuospatial and verbal memory processes in short-term, working, and long-term memories in 345 adults. Beginning in the 20s, a continuous, regular decline occurs for processing-intensive tasks (e.g., speed of processing, working memory, and long-term memory), whereas verbal knowledge increases across the life span. There is little differentiation in the cognitive architecture of memory across the life span. Visuospatial and verbal working memory are distinct but highly interrelated systems with domain-specific short-term memory subsystems. In contrast to recent neuroimaging data, there is little evidence for dedifferentiation of function at the behavioral level in old compared with young adults. The authors conclude that efforts to connect behavioral and brain data yield a more complete understanding of the aging mind. The present study is a life span approach to understanding visuospatial and verbal working memory and its relationship to long-term memory. It is well-documented that measures of overall cognitive resource such as speed of processing and working memory capacity mediate virtually all age-related variance on higher order cognitive tasks, including long-term memory tasks (Hultsch,
The Elusive nature of executive functions: A review of our current understanding
- Neuropsychological Review
, 2007
"... Abstract Executive functions include abilities of goal formation, planning, carrying out goal-directed plans, and effective performance. This article aims at reviewing some of the current knowledge surrounding executive functioning and presenting the contrasting views regarding this concept. The neu ..."
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Cited by 87 (0 self)
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Abstract Executive functions include abilities of goal formation, planning, carrying out goal-directed plans, and effective performance. This article aims at reviewing some of the current knowledge surrounding executive functioning and presenting the contrasting views regarding this concept. The neural substrates of the executive system are examined as well as the evolution of executive functioning, from development to decline. There is clear evidence of the vulnerability of executive functions to the effects of age over lifespan. The first executive function to emerge in children is the ability to inhibit overlearned behavior and the last to appear is verbal fluency. Inhibition of irrelevant information seems to decline earlier than set shifting and verbal fluency during senescence. The sequential progres-sion and decline of these functions has been paralleled with the anatomical changes of the frontal lobe and its connections with other brain areas. Generalization of the results presented here are limited due to methodological differences across studies. Analysis of these differences is presented and suggestions for future research are offered.
Context processing in older adults: evidence for a theory relating cognitive control to neurobiology in healthy aging
, 2001
"... A theory of cognitive aging is presented in which healthy older adults are hypothesized to suffer from disturbances in the processing of context that impair cognitive control function across multiple domains, including attention, inhibition, and working memory. These cognitive disturbances are postu ..."
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Cited by 79 (12 self)
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A theory of cognitive aging is presented in which healthy older adults are hypothesized to suffer from disturbances in the processing of context that impair cognitive control function across multiple domains, including attention, inhibition, and working memory. These cognitive disturbances are postulated to be directly related to age-related decline in the function of the dopamine (DA) system in the prefrontal cortex (PFC). A connectionist computational model is described that implements specific mechanisms for the role of DA and PFC in context processing. The behavioral predictions of the model were tested in a large sample of older (N = 81) and young (N = 175) adults performing variants of a simple cognitive control task that placed differential demands on context processing. Older adults exhibited both perfor-mance decrements and, counterintuitively, performance improvements that are in close agreement with model predictions. There are a number of cognitive and biological changes that appear to occur during healthy aging. At the cognitive level, these changes include declines in functions such as episodic and work-ing memory, attention, and inhibition (e.g., Hasher & Zacks, 1988; Moscovitch & Winocur, 1995; Salthouse, 1990; Spieler, Balota, &
Enrichment effects on adult cognitive development: Can the functional capacity of older adults be preserved and enhanced
- Psychological Science in the Public Interest
, 2008
"... SUMMARY—In this monograph, we ask whether various kinds of intellectual, physical, and social activities pro-duce cognitive enrichment effects—that is, whether they improve cognitive performance at different points of the adult life span, with a particular emphasis on old age. We begin with a theore ..."
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Cited by 78 (7 self)
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SUMMARY—In this monograph, we ask whether various kinds of intellectual, physical, and social activities pro-duce cognitive enrichment effects—that is, whether they improve cognitive performance at different points of the adult life span, with a particular emphasis on old age. We begin with a theoretical framework that emphasizes the potential of behavior to influence levels of cognitive functioning. According to this framework, the undeniable presence of age-related decline in cognition does not in-validate the view that behavior can enhance cognitive functioning. Instead, the course of normal aging shapes a zone of possible functioning, which reflects person-specific endowments and age-related constraints. Individuals in-fluence whether they function in the higher or lower ranges of this zone by engaging in or refraining from beneficial
Genetics of cognition: outline of a collaborative twin study. Twin Res
, 2001
"... Amultidisciplinary collaborative study examining cognition in a large sample of twins is outlined. A common experimental ..."
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Cited by 63 (22 self)
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Amultidisciplinary collaborative study examining cognition in a large sample of twins is outlined. A common experimental
Comparative longitudinal structural analyses of the growth and decline of multiple intellectual abilities over the life span. Dev Psychol
, 2002
"... Latent growth curve techniques and longitudinal data are used to examine predictions from the theory of ..."
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Cited by 60 (10 self)
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Latent growth curve techniques and longitudinal data are used to examine predictions from the theory of
Language deficits, localization, and grammar: Evidence for a distributive model of language breakdown in aphasic patients and neurologically intact individuals
- Psychological Review
, 2001
"... Selective deficits in aphasics patients ’ grammatical production and comprehension are often cited as evidence that syntactic processing is modular and localizable in discrete areas of the brain (e.g., Y. Grodzinsky, 2000). The authors review a large body of experimental evidence suggesting that mor ..."
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Cited by 58 (9 self)
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Selective deficits in aphasics patients ’ grammatical production and comprehension are often cited as evidence that syntactic processing is modular and localizable in discrete areas of the brain (e.g., Y. Grodzinsky, 2000). The authors review a large body of experimental evidence suggesting that morphosyntactic deficits can be observed in a number of aphasic and neurologically intact populations. They present new data showing that receptive agrammatism is found not only over a range of aphasic groups, but is also observed in neurologically intact individuals processing under stressful conditions. The authors suggest that these data are most compatible with a domain-general account of language, one that emphasizes the interaction of linguistic distributions with the properties of an associative processor working under normal or suboptimal conditions. The primary purpose of this article is to provide empirical arguments in support of a new view of language deficits and their neural correlates, particularly in the realm of syntax. Selective syntactic deficits are often cited as evidence that the human brain contains a bounded and well-defined faculty or module dedicated exclusively to the representation and/or processing of syntax (Caplan & Waters, 1999; Grodzinsky, 1995a,
A diffusion model analysis of the effects of aging in the lexical-decision task
- Psychology and Aging
, 2004
"... The effects of aging on response time (RT) are examined in 2 lexical-decision experiments with young and older subjects (age 60–75). The results show that the older subjects were slower than the young subjects, but more accurate. R. Ratcliff’s (1978) diffusion model provided a good account of RTs, t ..."
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Cited by 57 (25 self)
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The effects of aging on response time (RT) are examined in 2 lexical-decision experiments with young and older subjects (age 60–75). The results show that the older subjects were slower than the young subjects, but more accurate. R. Ratcliff’s (1978) diffusion model provided a good account of RTs, their distributions, and response accuracy. The fits show an 80–100-ms slowing of the nondecision components of RT for older subjects relative to young subjects and more conservative decision criterion settings for older subjects than for young subjects. The rates of accumulation of evidence were not significantly different for older compared with young subjects (less than 2 % and 5 % higher for older subjects relative to young subjects in the 2 experiments). Across a wide variety of cognitive tasks, research has shown that processing slows with age. For some tasks, especially those like letter discrimination that depend heavily on peripheral processes, this is not surprising (e.g., Thapar, Ratcliff, & McKoon, 2003). However, for other tasks it might be expected that performance would improve with age. One such task is lexical decision, the task of interest in this article. Over a lifetime of 60 to 70 years, the number of encounters with many words must greatly exceed the number of encounters in the first 20 years. Yet despite so many years of practice, lexical-decision response times (RTs) increase with age. For example, Allen, Madden, and Crozier (1991) found average RTs of 800 ms for older adults compared with 500 ms for young adults. Word frequency effects, longer RTs with lower frequency words, are also larger for older adults (see Allen et al.,
A Source Activation Theory of Working Memory: Cross-talk Prediction . . .
- Journal of Cognitive Systems Research
, 2000
"... Over the decades, computational models of human cognition have advanced from programs that produce output similar to that of human problem solvers to systems that mimic both the products and processes of human performance. In this paper, we describe a model that achieves the next step in this pro ..."
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Cited by 55 (3 self)
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Over the decades, computational models of human cognition have advanced from programs that produce output similar to that of human problem solvers to systems that mimic both the products and processes of human performance. In this paper, we describe a model that achieves the next step in this progression: predicting individual participants' performance across multiple tasks after estimating a single individual difference parameter. We demonstrate this capability in the context of a model of working memory, where the individual difference parameter for each participant represents working memory capacity. Specifically, our model is able to make zero-parameter predictions of individual participants' performance on a second task after separately fitting performance on a preliminary task. We argue that this level of predictive ability offers an important test of the theory underlying our model.
Age, executive function, and social decision making: A dorsolateral prefrontal theory of cognitive aging
- Psychology and Aging
, 2002
"... Current neuropsychological models propose that some age-related cognitive changes are due to frontallobe deterioration. However, these models have not considered the possible subdivision of the frontal lobes into the dorsolateral and ventromedial regions. This study assessed the age effects on 3 tas ..."
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Cited by 52 (1 self)
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Current neuropsychological models propose that some age-related cognitive changes are due to frontallobe deterioration. However, these models have not considered the possible subdivision of the frontal lobes into the dorsolateral and ventromedial regions. This study assessed the age effects on 3 tasks of executive function and working memory, tasks dependent on dorsolateral prefrontal dysfunction; and 3 tasks of emotion and social decision making, tasks dependent on ventromedial prefrontal dysfunction. Age-related differences in performance were found on all tasks dependent on dorsolateral prefrontal dysfunction. In contrast, age-related differences were not found on the majority of the tasks dependent on ventromedial prefrontal dysfunction. The results support a specific dorsolateral prefrontal theory of cognitive changes with age, rather than a global decline in frontal-lobe function. Healthy adult aging is associated with the deterioration of the frontal lobes of the brain, earlier and more severely than other brain areas (Haug et al., 1983). Current neuropsychological models propose that it is this frontal-lobe deterioration that is responsible for many age-related cognitive changes (Daigneault & Braun, 1993; Moscovitch & Winocur, 1995; West, 1996). Furthermore,
