Biomedical subjects

P Verhaeghen

Publications and source records attributed to P Verhaeghen.

10 recordsLinked to original sources

PubMed1998

Aging and the Stroop effect: a meta-analysis.

In this meta-analysis, data from 20 studies comparing younger and older adults on the Stroop interference effect, contained in 15 articles, were analyzed. No significant difference was found in the Stroop interference effect, expressed as mean standardized difference, between the 2 age groups (for younger adults: d = 2.04; for older adults: d = 2.17). Moderator variables were present, but these did not produce age differences. Brinley analysis showed that a single regression line with a slowing factor of 1.9 described the data well (R2 = .83) and confirmed that no Age x Condition interaction was present in the data. Likewise, no Age x Condition interaction was found when the data were fitted to the information loss model; the age ratio of decay rates was estimated to be 1.4. Consequently, the apparent age-sensitivity of the Stroop interference effect appears to be merely an artifact of general slowing.

Adult↗

PubMed1998

Aging and the negative priming effect: a meta-analysis.

This article reports results from a meta-analysis on adult age differences in the negative priming effect (21 studies on identity negative priming and 8 on location negative priming). Both younger and older adults were found to be susceptible to the negative priming effect in identity and location tasks. Effect sizes were homogeneous for both tasks, indicating that the data are adequately described without reference to moderator variables. State trace analysis on identity tasks, in which mean latencies in negative priming conditions were regressed onto mean latencies in baseline conditions, showed (a) that in both age groups the negative priming effect is proportional rather than additive and (b) that the negative priming effect is smaller in older adults as compared with younger adults.

Adult↗

PubMed1997

Sequential and coordinative complexity in time-accuracy functions for mental arithmetic.

Time-accuracy functions for tasks involving single-digit mental addition and subtraction were derived in a sample of 18 younger (mean age = 21.7 years) and 16 older adults (mean age = 68.8 years). Sequential complexity was manipulated by varying the number of operations (5 vs. 10); coordinative complexity was induced by bracketing. Age differences were apparent in the coordinative conditions, even though no age difference was present in the sequential conditions. This indicates that the age difference under conditions of high coordinative demands could not be attributed solely to a decline in basic speed of processing. The Age x Complexity interaction was due to larger onset times and lower asymptotic performance by the older adults in the coordinative conditions but not due to to rate of approach to the asymptote. This implies that coordinative demands do not differentially hurt access from semantic memory in older adults; however, coordinative demands do have disproportionately negative consequences for computation speed and self-monitoring in older adults.

Adult↗

PubMed1997

Meta-analyses of age-cognition relations in adulthood: estimates of linear and nonlinear age effects and structural models.

A meta-analysis was conducted on 91 studies to derive a correlation matrix for adult age, speed of processing, primary-working memory, episodic memory, reasoning, and spatial ability. Structural equation modeling with a single latent common cognitive factor showed that all cognitive measures shared substantial portions of age-related variance. A mediational model revealed that speed of processing and primary-working memory appear to be important mediators of age-related differences in the other measures. However, not all of the age-related influences were mediated. An examination of quadratic age effects and correlational patterns for subsamples under and over 50 years of age revealed that (a) negative age-cognition relations were significant for the 18- to 50-year-old sample and (b) the age-related decline accelerated significantly over the adult life span for variables assessing speed, reasoning, and episodic memory.

Adult↗

PubMed1996

On the mechanisms of plasticity in young and older adults after instruction in the method of loci: evidence for an amplification model.

A meta-analytic review of the literature points out that young adults benefit more from instruction in mnemonic techniques than do older adults. In a study on memory plasticity after instruction in the method of loci, it was found that the cognitive mechanisms of plasticity in young and older adults are largely identical, with the age-related variables of speed of mental operations, associative memory, and number of list rehearsals as the core influences on plasticity. The data fit an amplification model of plasticity, in which variables positively associated with pretest performance and negatively associated with age are positively related to plasticity. Also, older adults were found to comply less with instructions, and when complying, to apply the method of loci correctly less often. Noncompliance, incorrect strategy use, and amplification might explain the adult age differences in treatment gain after instruction in a mnemonic technique.

Adolescent↗

PubMed1993

Memory aging as a general phenomenon: episodic recall of older adults is a function of episodic recall of young adults.

The focus of this study was on the relationship between young and older adults' performance on tasks of deliberate recall from episodic memory. A meta-analysis on 91 relevant studies (comprising a total of 154 conditions) was conducted. It was found that 83% of the variance in older adults' recall probability was accounted for by a quadratic function using young adults' recall probabilities as predictors. No significant interaction with age of older adults was found. Interaction with task type was, however, significant, resulting in separate functions for list recall, prose recall, and paired-associate recall. The results point at the importance of the main effect of age in studies on memory aging.

Adolescent↗

PubMed1993

Facts and fiction about memory aging: a quantitative integration of research findings.

A meta-analytic literature review on adult age differences in speed of search in short-term memory (12 studies), memory span (40 studies), list recall (68 studies), paired-associate recall (21 studies), and prose recall (39 studies) is presented. Results show that age differences are quite large (depending on the task, elderly people can be situated between the 3rd and the 38th percentile of the adult age memory performance distribution) and quasi-omnipresent, even under conditions of cued recall or semantic task orientation. Evidence for age sensitivity is found for the process of categorization of lists, but not for semantic processing, association strategies, imagery, nor for extracting main points from prose material. The elderly population benefits more than the young from the possibility of reviewing lists or texts. Differences between young adults and old-old adults are larger than between young adults and the young-old for speed of search in short-term memory and prose recall only. In two out of the five tasks, lower education is reliably associated with larger age differences.

Adolescent↗

PubMed1993

More or less the same? A memorability analysis on episodic memory tasks in young and older adults.

A relative memorability analysis was conducted on a young (19.5 years, n = 48) and an old (67.0 years, n = 45) age group, using 10 episodic memory tasks (four lists of words, four lists of paired associates, and two texts). Probability of recall of individual items (lists) or idea units (texts) by the older adults could be predicted from probability of recall for the corresponding items or idea units by the young adults, with a median correlation (corrected for test unreliability) of .88. It was found that the same item characteristics predicted recall probability of individual items or idea units in both age groups. For lists of words and texts, no differences were found in the slopes of the regression functions relating item characteristics to recall probability in the two age groups. For 3 of 4 lists of paired associates, the slopes for item characteristics significantly predicting recall probability were reliably larger for the older adults as compared with the young adults. It can be concluded that age differences in deliberate recall are to a large amount quantitative, and not qualitative, in nature.

Adolescent↗

PubMed1992

Improving memory performance in the aged through mnemonic training: a meta-analytic study.

The effectiveness of memory training for the elderly was examined through a meta-analysis of pre-to-posttest gains on episodic memory tasks in healthy subjects aged 60 or above. Pre-to-posttest gains were found to be significantly larger in training groups (0.73 SD, k = 49) than in both control (0.38 SD, k = 10) and placebo (0.37 SD, k = 8) groups. Treatment gains in training groups were negatively affected by age of participants and duration of training sessions and positively affected by group treatment, pretraining, and memory-related interventions. No differences in treatment gain were obtained as a function of type of mnemonic taught nor the kind of pretraining used.

Aged↗

PubMedDate not supplied

Growing slower and less accurate: adult age differences in time-accuracy functions for recall and recognition from episodic memory.

In 2 experiments, time-accuracy curves were derived for recall and recognition from episodic memory for both young and older adults. In Experiment 1, time-accuracy functions were estimated for free list recall and list recall cued by rhyme words or semantic associations for 13 young and 13 older participants. In Experiment 2, time-accuracy functions were estimated for recognition of word lists with or without distractor items and with or without articulatory suppression for 29 young and 30 older participants. In both studies, age differences were found in the asymptote (i.e., the maximum level of performance attainable) and in the rate of approach toward the asymptote (i.e., the steepness of the curve). These two parameters were only modestly correlated. In Experiment 2, it was found that 89% of the age-related variance in the rate of approach and 62% of the age-related variance in the asymptote was explained by perceptual speed. The data point at the existence of 2 distinct effects of aging on episodic memory, namely a dynamic effect (growing slower) and an asymptotic effect (growing less accurate). The absence of Age x Condition interactions in the age-related parameters in either experiment points at the rather general nature of both aging effects.

Adult↗