The processing-speed theory of adult age differences in cognition

“Research has established that a general speed factor underlies many cognitive tasks (Salthouse, 1996) and that this factor tends to influence magnitudes of treatment effects for subjects who differ in response speed.”

“Based on the relevance of PS for age-related cognitive decline in general [Salthouse, 1996], it seems that maintained FC strength with age despite WM integrity loss may be of great importance for healthy cognitive aging.”

“This is exciting given the noninvasive nature of a 1-hr booster session in light of the negative effects of the age-related processing speed mechanism on cognition and its impact on daily functioning (Salthouse, 1996).”

“In addition to these declines in audition, adult aging is often also accompanied by reduced cognitive efficiency, most notably in working memory and attentional resources (Craik and Byrd, 1982; Salthouse, 1994), and a general slowing in a number of perceptual and cognitive domains (Salthouse, 1996).”

“With regard to specific cognitive functioning changes over the lifespan in the normal population, there is evidence that processing speed and other control processes improve from infancy to young adulthood and then decline from the twenties to old age (Salthouse, 1996).”

“Several studies report age-related cognitive impairments in healthy individuals (Huppert and Kopelman, 1989; Salthouse, 1996; Daum et al., 1996; Le Moal et al., 1997; File et al., 1999; Small et al., 1999; Fluck et al., 2001, MacPherson et al., 2002).”

“This may simply be because the participants are among the most educated in their country and are at an age whenRTs are near their life-spanminimum (38, 39).”

“General processing speed has previously been suggested as being the cause of ageing-related differences in a great variety of cognitive tasks (e.g., Kail & Salthouse, 1994; Salthouse, 1996).”

“, 2008b), we found that this same SNP influenced, even in healthy individuals, frontostriatal cognitive tasks taxing processing speed, IQ and executive cognitive control, cardinal DA-mediated cognitive functions (Alexander et al., 1986; Kane & Engle, 2002; Pantelis et al., 1997; Salthouse, 1996), as well as ‘‘tuning’’…”

“Age related hearing loss, age-related declines in attention resources (28), working memory capacity (9), and processing speed (29) are some the factors that inhibit the memory of the older adults and further complicate the evaluation of the food habits of the oldest adults.”

“Stroop ratio and symbol digit coding, which are the classic measures of perceptual and processing speed in aging, loaded significantly on this component (Salthouse, 1996).”

“differences in the processes and mechanisms related to TOJ discussed below (Baudouin, Vanneste, & Isingrini, 2004; Craik & Hay, 1999; Fitzgibbons & Gordon-Salant, 1998; Gordon-Salant & Fitzgibbons, 1999; Salthouse, 1996; Surwillo, 1968; Vanneste, Pouthas, & Wearden, 2001).”

“While speed of processing (Salthouse, 1996) and executive function (Bryan & Luszcz, 2000a; Bryan, Luszcz, & Pointer, 1999; Crawford, Bryan, Luszcz, Obonsawin, & Stewart, 2000) decline with increasing age, verbal ability tends to be well-maintained (Horn, 1982; Salthouse 1982).”

“…which parsimoniously explain numerous findings of age-related change in cognitive and motor functioning by the rise and fall of basic aspects of information processing (e.g., speed, attentional control) over the life span (Cepeda, Kramer, & de Sather, 2001; Kail, 1991; Salthouse, 1996).”

“As noted earlier, a large number of other studies have also found there to be either no age effects (Parkin et al., 1995; Salthouse, 1996 ) or age improvement in phonemic fluency (Parkin & Walter, 1991; Veroff, 1980; Yeudall et al., 1986).”

“Tun and Wingfield (1999) found that speed of information processing predicted listening performance in conditions with one and two competing talkers.”

“…and processing speed are generally considered components of fluid intelligence (e.g., Birren & Fisher, 1995; e.g., Lindenberger, Mayr, & Kleigl, 1993; Salthouse, 1996), although processing speed can be conceptualized as a separate construct (e.g., Cattell, 1971; Horn & Hofer, 1992; Schaie, 2005).”

“This effect may well be482 connected to the large proportion of cognitive performance decrease explained483 by processing speed changes in aging (Salthouse, 1996), as the system needs484 higher overall activation and provides lower communication efficiency.”

“To explain age-related declines in cognitive functions, two concurrent hypotheses dominate current research: the executive decline hypothesis (Raz, 2000; West, 1996) and the processing speed slowing hypothesis ( Salthouse, 1996 ).”

“511–520 processing (Madden, 1990; Salthouse, 1996) limit the ability of older adults to perform memory encoding and retrieval operations effectively.”

“Perceptual speed is conceptually closer to a resource than many other abilities (Anstey et al., 2003; Salthouse, 1996) and can serve as a robust and parsimonious proxy for multivariate assessments of cognitive ability (Lindenberger & Ghisletta, 2009).”

“If a strategy (such as categorical clustering) is more effortful for one culture than another, the culture effects should be particularly pronounced with age due to (a) cognitive resource limitations such as decreased speed of processing and working memory capacity that occur with age [ ,”

“…including both cross-sectional studies and longitudinal studies, has investigated changes in cognitive function with aging, and findings reveal that working memory, information processing, selective attention, and problem-solving ability show differential decline with aging (e.g., Salthouse, 1996).”

“This is important, because given the slower processing and reduced capacity that accompanies aging (Salthouse, 1996), deficits in 2nd and higher-order learning might reflect a reduced availability of the events to be associated, rather than a learning deficit per se.”

“Keywords: Dementia, information processing speed, mild cognitive impairment, reaction time”

“…task because of its nonspecific sensitivity to a variety of demographic factors, for example, age (Hartshorne and Germine, 2015), intelligence and cognition (Salthouse, 1996), neurological health (Longstreth et al., 2005), mental health (Dickinson et al., 2007), and mortality (Fried, 1998).”

“Recent evidence suggests that cognitive speed in particular may be strongly related to functional abilities [ ,”

“However, the present speech error results challenge the multifactor theory of Salthouse (1996) , in which one factor (general slowing) degrades cognitive performance through its effects on another factor (forgetting or unavailability of the products of earlier processing at the time when later processing requires thos…”

“The duration of a step depends on the amount of information that is available at the onset of that step (cf. Salthouse, 1996).”

“(Salthouse, 1996) and with respect to efficacy (Hasher et al.”

“These suggestions include the proposal of a general slowing of cognitive processing (Salthouse, 1996), reduced self-initiated processing (Craik, 1986), a reduction in recollective experience (Jacoby & Hay, 1998), or a specific deficit to build and maintain associations (Naveh-Benjamin, 2000).”

“The results of Experiment 1 have implications for a cognitive-slowing account ( Salthouse, 1985, 1996 ) of”

“Several criteria have been proposed to guide the selection of measures used to assess processing speed: relative simple task, the speed measure should not merely represent the input and output processes or sensory and motor processes, it is desirable that the construct be evaluated with several measures to minimize th…”

“Since age group differences in information processing speed (Salthouse, 1996) or attention capabilities may be partially responsible for potential performance differences between the older adults of Experiment 5 and the young adults of Experiments 2 and 4, we investigated how the older group compared to the young adul…”

“Important for the present investigation is that extant models of cognitive aging (e.g., Salthouse, 1985, 1996) postulate a general age-related slowing of cognitive processes, including internal clock mechanisms (Salthouse, Wright, & Ellis, 1979; see Drake, Jones, & Baruch, 2000, for similar claims…”

“Based on previous studies of reaction time (Salthouse 1996) and cognitive task switching (Kramer et al. 1999; DiGirolamo et al. 2001), we predicted that old participants would take longer to implement pattern change than young participants.”

“Given that responses were slower overall for older adults than for younger adults, the larger general savings for older adults than for younger adults could be due to a generalized slowing of all mental processes with age (e.g., Cerella, 1990; Salthouse, 1996).”

“Furthermore, it has been advanced that changes in performance between older and younger observers might be explained by an age-related general slow-down of information processing (Salthouse, 1996).”

“Salthouse (1991) proposed that age-related changes in ‘‘fluid’’ cognition, such as memory, reasoning, and spatial abilities, are due to a decrease in the speed with which cognitive operations may be carried out (see Salthouse, 1996, for a review).”

“When age progresses, the brain is subjected to many changes that are related to deterioration of sensory, motor and intellectual functioning (Salthouse, 1996; Li and Lindenberger, 2002; Fandakova et al., 2014).”

“In most cognitive tasks, older adults are slower than younger adults, and even slower on the most demanding cognitive tasks (see Salthouse, 1996, for a review).”

“…times (Ferreira, Simões, and Marôco 2013), cognitive impairments, including information processing speed, attention switch, memory and problem solving (Brouwer et al. 1991; Salthouse 1996; Pollatsek, Romoser, and Fisher 2012) as well as declining psychomotor abilities (Staplin et al. 1999).”

“Salthouse (1996) theorized in the processing-speed theory that age-associated deficits in cognitive functioning are due to the reduction in the speed of processing operations leading to difficulties in the storage of information.”

“There are numerous theories regarding the underlying cause of such age-related memory problems, including general cognitive slowing (e.g., Salthouse, 1995, 1996), sensory difficulties (Schneider & Pichora-Fuller, 2000), and decreases in attentional processing resources (e.g., Cerella, 1985; Craik &…”

“N: 0006-3223 SEE COMMENTA Salthouse (10) defined processing speed as the number of correct responses an individual is able to make within a finite amount of time.”

“Age-related slowing is commonly observed on speeded tasks (Salthouse, 1996).”

“F or p er so na l u se o nl y. cognitive control, there are clear losses in processing speed (Salthouse 1996), formation and retrieval of associative information (Naveh-Benjamin 2000), and inhibitory control (Hasher&Zacks 1988).”

“In addition, a poor performance in this task may also be observed in normal aging, with attention and processing-speed abilities being proposed as crucial age-related markers of cognitive dysfunction.(32) Hence, this evidence underlines that SDMT is a clinically useful test to capture the multifactorial nature of PD c…”

“The relation between performance and activation suggests age differences in activation–response time relationships, and is consistent with behavioral data suggesting that processing speed is an important variable in age-related performance variation (Salthouse, 1996).”

“Different theories attribute the episodic memory deficit in old age to a failure of meta-memory (Hertzog, Kidder, Powell-Moman, & Dunlosky, 2002), a failure of inhibitory processing (Hasher & Zacks, 1988), or a reduction in processing speed (Salthouse, 1996; see Light, 1991 for a review).”

“It has been proposed [22] that these proportional interference scores minimize the effects of general slowing, which is often highlighted as a potential explanation of the magnitude of the Stroop effect in the elderly [35–37].”

“Age-related deficits in white matter integrity, for example, may induce rather task-independent age effects as they can decelerate conduction speed and therefore slow down responses in most cognitive domains (for reviews, see Raz 2000; Salthouse 1996).”

“This pattern suggests that age-related cognitive changes may be due primarily to a generalized, age-related slowing of elementary perceptual processing (Salthouse, 1996; Salthouse, Atkinson, & Berish, 2003).”

“, increased reaction time) in simple and complex tasks [57].”

“Alternatively, comorbidities of aging known to increase risk for cognitive impairment (Salthouse, 1996) may be predisposed or accelerated in the context of HIV infection, including cardiovascular disease (e.g., hypertension, hyperlipidemia), cerebrovascular events, and metabolic dysregulation…”

“…observed may be due at least in part to the age-related declines in working memory (the online mental capacity for processing verbal and spatial information; see Baddeley, 1986) or to agerelated declines in perceptual speed (the speed at which mental operations are performed ; Salthouse, 1996).”

“meta-regression is limited when based on a few trials [15].”