Models of visuospatial and verbal memory across the adult life span.

Abstract

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 Generality of Working Memory Capacity: A Latent-Variable Approach to Verbal and Visuospatial Memory Span and Reasoning.

“…Whereas verbal storage-rehearsal processes were correlated strongly with verbal reasoning and very weakly with general ability (see also Cantor et al, 1991;, spatial storage-rehearsal processes predicted both spatial reasoning and general fluid ability strongly. As we noted earlier, these findings are consistent with others demonstrating a close link between "simple" spatial storage and higher order cognitive capabilities such as executive function (Miyake et al, 2001), complex reasoning and Gf (Oberauer, in press;Shah & Miyake, 1996), and free recall of either verbal or visuospatial materials (Park et al, 2002). However, we also found that when our Gf factor was defined in a less spatially biased manner, spatial storage had a substantially weaker correlation with it.…”

“…How should we reconcile these discrepant findings? Park et al (2002) also failed to differentiate the WMC-STM relation across verbal and spatial domains, and therefore ours is not the first failure to replicate. In the Park et al data, the correlation between spatial WMC and STM latent variables was, again, not significantly larger than that between verbal WMC and STM (.84 and .80, respectively).…”

“…One can make reasonable arguments for or against including correlated errors in structural models, therefore we would most confidently and conservatively say that verbal and spatial WMC share at least 70% of their variance, and therefore WM span measures capture primarily domain-general variance in cognitive ability. Indeed, other recent latent-variable studies have similarly pointed to either a unitary WMC across verbal and spatial domains or distinguishable verbal and spatial WMCs that share 70%-90% of their variance (Ackerman et al, 2002;Kyllonen, 1993;Law et al, 1995;Oberauer et al, 2000Oberauer et al, , 2003Park et al, 2002;Salthouse, 1995;Swanson, 1996). STM span, in contrast, appears to tap more domain-specific storage and rehearsal capabilities (although not entirely specific, as verbal and spatial STM shared 40% of their variance), which fits with the experimental and neuropsychological data that have been used to support fractionated WM models such as Baddeley's (1986Baddeley's ( , 2000.…”

Basal forebrain integrity and cognitive memory profile in healthy aging

“…1). This confirms existing behavioral evidence suggesting that individual differences in long-term memory correlated with individual differences in working memory (Park et al, 2002(Park et al, , 1996Verhaeghen and Salthouse, 1997). Although verbal fluency tasks are commonly used neuropsychological indicators of frontal lobe dysfunction (Bryan and Luszcz, 2000), which are particularly sensitive Legend: The second column of each correlation indicates the statistical significance (P-value).…”

Synaptic plasticity in early aging

“…However, work on cohorts of human subjects for the third through ninth decades of life indicates that memory loss begins early in adulthood and then continues to worsen in an almost linear fashion, leading to a situation in which the magnitude of decline from 20 to 30 is about as great as that from 70 to 80 years of age (Park et al, 2002). That memory deteriorates during the course of normal aging comes as no surprise to middle-aged people, but that it begins so early and progresses so steadily is perhaps unexpected.…”