Memory Factors in Age-Related Differences in Simple Reasoning

Adults in their 50s were compared with adults in their late teens or 20s in the accuracy of relatively simple reasoning decisions involving varying amounts of information. Because the magnitude of the age differences in decision accuracy was independent of the amount of information relevant to the decision, it was suggested that adults in their 20s and 50s do not differ in the effectiveness of integrating information across multiple premises. However, the 2 groups differed in the accuracy of trials involving only a single relevant premise, and thus it was inferred that 1 factor contributing to reasoning differences within the age range from 20 to 60 may be a failure to encode, or retain, relevant information

Memory and Age Differences in Spatial Manipulation Ability

Young and old adults were asked, in 3 experiments, to make decisions about the identity of line segment patterns after either adding or subtracting line segments from the original pattern. On some of the trials, the line segments from the initial display were presented again in the second display to minimize the necessity of remembering early information during the processing of later information. Although this manipulation presumably reduced the importance of memory in the tasks, it had little effect on the magnitude of the age differences in any of the experiments. Because the 2 groups were equivalent in accuracy of simple recognition judgments, but older adults were less accurate when the same types of decisions were required in the context of an ongoing task, the results suggested that older adults may be impaired in the ability to retain information while simultaneously processing the same or other information

Age and experience effects in spatial visualization

Three studies were conducted to investigate effects related to age and experience on measures of spatial visualization ability. All research participants were college-educated men; those in the experienced group were practicing or recently retired architects. The major results of the studies were (a) that increased age was found to be associated with lower levels of performance on several tests of spatial visualization and (b) that this was true both for unselected adults and for adults with extensive spatial visualization experience. These findings seem to suggest that age-related effects in some aspects of cognitive functioning may be independent of experiential influences. (PsycINFO Database Record (c) 2016 APA, all rights reserved

Investigating ceiling effects in longitudinal data analysis

Score limitation at the top of a scale is commonly termed "ceiling effect." Ceiling effects can lead to serious artifactual parameter estimates in most data analysis. This study examines the consequences of ceiling effects in longitudinal data analysis and investigates several methods of dealing with ceiling effects through Monte Carlo simulations and empirical data analyses. Data were simulated based on a latent growth curve model with T D 5 occasions. The proportion of the ceiling data [10%-40%] was manipulated by using different thresholds, and estimated parameters were examined for R D 500 replications. The results showed that ceiling effects led to incorrect model selection and biased parameter estimation (shape of the curve and magnitude of the changes) when regular growth curve models were applied. The Tobit growth curve model, instead, performed very well in dealing with ceiling effects in longitudinal data analysis. The Tobit growth curve model was then applied in an empirical cognitive aging study and the results were discussed

Processing rate and adult age differences in cognition

Issued as Final report, Project no. G-42-628 (continues Project no. G-42-620