Erika Borella

Working memory training in older adults: evidence of transfer and maintenance effects.

Few studies have examined working memory (WM) training-related gains and their transfer and maintenance effects in older adults. This present research investigates the efficacy of a verbal WM training program in adults aged 65-75 years, considering specific training gains on a verbal WM (criterion) task as well as transfer effects on measures of visuospatial WM, short-term memory, inhibition, processing speed, and fluid intelligence. Maintenance of training benefits was evaluated at 8-month follow-up. Trained older adults showed higher performance than did controls on the criterion task and maintained this benefit after 8 months. Substantial general transfer effects were found for the trained group, but not for the control one. Transfer maintenance gains were found at follow-up, but only for fluid intelligence and processing speed tasks. The results are discussed in terms of cognitive plasticity in older adults.

The Specific Role of Inhibition in Reading Comprehension in Good and Poor Comprehenders

Difficulties in inhibitory processes have been shown to characterize the performance of poor comprehenders. However, the inhibitory inefficiency of poor comprehenders is most often assessed by their resistance to proactive interference, that is, the ability to suppress off-goal task information from working memory (WM). In two studies tasks assessing resistance to proactive interference (intrusion errors), response to distracters (Text With Distracters task) and prepotent response inhibition (Stroop and Hayling tests), along with WM measures, were administered to children aged 10 to 11, both good and poor comprehenders. The aim of the study was to specifically determine whether general or specific inhibitory factors affect poor comprehenders’ reading difficulties. Results showed that poor comprehenders, compared to good ones, are impaired in WM tasks and in inhibitory tasks that assess resistance to proactive interference. This suggests that reading comprehension difficulties of poor comprehenders are related to specific inhibitory problems.

Does Strategic Memory Training Improve the Working Memory Performance of Younger and Older Adults

The paper examines the effect of strategic training on the performance of younger and older adults in an immediate list-recall and a working memory task. The experimental groups of younger and older adults received three sessions of memory training, teaching the use of mental images to improve the memorization of word lists. In contrast, the control groups were not instructed to use any particular strategy, but they were requested to carry out the memory exercises. The results showed that strategic training improved performance of both the younger and older experimental groups in the immediate list recall and in the working memory task. Of particular interest, the improvement in working memory performance of the older experimental group was comparable to that of the younger experimental group.

Age Differences in Text Processing: The Role of Working Memory, Inhibition, and Processing Speed

OBJECTIVES Age-related changes in the efficiency of various general cognitive mechanisms have been evoked to account for age-related differences between young and older adults in text comprehension performance. Using structural equation modeling, we investigate the relationship between age, working memory (WM), inhibition-related mechanisms, processing speed, and text comprehension, focusing on surface and text-based levels of processing. METHODS Eighty-nine younger (M = 23.11 years) and 102 older (M = 70.50 years) adults were presented text comprehension, WM, inhibition, and processing speed tasks. In the text comprehension task, the demand on the memory system was manipulated, by allowing (text present) or not (text absent) viewing the text during the answering phase. RESULTS As expected, age differences were larger when the text was absent. The best fitting model showed that WM mediated the influence of age on both text processing conditions, whereas age-related variance in WM was, in turn, accounted for by processing speed and inhibition. DISCUSSION These findings confirm the hypothesis that WM capacity explains age differences in text processing, while it is itself accounted for by the efficiency of inhibiting irrelevant information and by speed of processing.

Working Memory and Inhibitory Control across the Life Span: Intrusion Errors in the Reading Span Test

The aim of this study was to examine to what extent inhibitory control and working memory capacity are related across the life span. Intrusion errors committed by children and younger and older adults were investigated in two versions of the Reading Span Test. In Experiment 1, a mixed Reading Span Test with items of various list lengths was administered. Older adults and children recalled fewer correct words and produced more intrusions than did young adults. Also, age-related differences were found in the type of intrusions committed. In Experiment 2, an adaptive Reading Span Test was administered, in which the list length of items was adapted to each individual’s working memory capacity. Age groups differed neither on correct recall nor on the rate of intrusions, but they differed on the type of intrusions. Altogether, these findings indicate that the availability of attentional resources influences the efficiency of inhibition across the life span.

Adult age differences in the Color Stroop Test: A comparison between an Item-by-item and a Blocked version

The Color Stroop Test is consensually considered as a task to assess the efficiency of inhibitory mechanisms. If the Stroop interference effect is largely undisputed, it is also acknowledged that the size of this effect varies as a function of various task manipulations, such as the task format. The aim of the present study was to compare the size of adult age-related differences in inhibition as assessed by two different versions of the Color Stroop Test: a standard Blocked paper-and-pencil version and a computerized Item-by-item one. Results showed pronounced age-related differences in the interference effect in the Blocked version, but not in the Item-by-item one. These findings are discussed in terms of the characteristics of the tasks. The choice of the appropriate version with respect to clinical aims is also addressed.

Reading Comprehension in Aging: The Role of Working Memory and Metacomprehension

Abstract This study examines age-related differences in reading comprehension analyzing the role of working memory and metacomprehension components in a sample of young (18–30 years), young-old (65–74 years), and old-old (75–85 years) participants. Text comprehension abilities were measured by a standardized test, including two texts: a narrative and an expository text. The elderlys reading comprehension performance, when compared to the norm, emerged to be adequate. More specifically, the young-old showed an equivalent level of comprehension as the young adults for the narrative text. However, a clear age-related decline was found in the case of the expository text. Hierarchical regression analyses showed that working memory capacity, as well as different metacomprehension components but not age, are the key aspects in explaining the different patterns of changes in the comprehension of narrative and expository texts.

Do working memory and susceptibility to interference predict individual differences in fluid intelligence

In the current study we examined the relationship between working memory capacity, inhibition/susceptibility to interference and fluid intelligence, measured by the Ravens Progressive Matrices (PM38), comparing groups of young (aged 18–35), young-old (aged 65–74), and old-old (aged 75–86) participants. Groups were administered two working memory tasks tapping into different mechanisms involved in working memory. The ability to control for irrelevant information was measured both considering memory errors (intrusion errors) in a working memory task and an index of susceptibility to interference obtained with a variant of the Brown-Peterson task. Regression analyses showed that the classical working memory measure was the most potent predictors of the Ravens score. Susceptibility to interference and intrusions errors contributed, but to a lower extent, to the Raven explained variance. These results confirm that working memory shares cognitive aspects with the fluid intelligence measure considered, whereas the role of inhibition to Raven scores is still in need of better evidence.

Interplay between memory and executive functions in normal and pathological aging.

Healthy older adults and Alzheimers disease (AD) patients are reported in the literature to be impaired in memory and executive functions. This research investigates the extent of these two abilities in determining pathological aging. Groups of young-old and old-old healthy people (Experiment 1) and individuals with amnestic mild cognitive impairment (a-MCI) and AD (Experiment 2) were administered verbal and visuo-spatial tests graded for memory and/or executive requirements. Results indicate a decline in visuo-spatial tasks requiring memory and executive functions in healthy aging. The a-MCI showed memory deficits similar to those shown by AD, but preserved executive functions. Executive function decline could be the critical feature of dementia.

Working memory training in old age: an examination of transfer and maintenance effects.

The present study examined the efficacy of a verbal working memory (WM) training program in old-old individuals (over 75 years of age). Thirty-six adults aged 75-87 took part in the study: 18 were randomly assigned to receive training and the remainder served as active controls. Specific training gains in a verbal WM task (criterion task), and transfer effects on measures of visuospatial WM, short-term memory, inhibition, processing speed, and fluid intelligence were examined. The trained old-old adults performed better than the controls in the criterion task, and this benefit persisted after 8 months; they also showed an increase in the efficiency of inhibitory mechanisms at follow-up compared with pretest. The results of this study suggest that the present WM training program produces benefits maintained over time even in old-old adults. These findings confirm that there is still room for plasticity in the basic mechanisms of cognition in advance old age.