Developmental Differences in the Ability to Provide Temporal Information About Repeated Events

Children (n = 372) aged 4–8 years participated in one or four occurrences of a similar event and were interviewed 1 week later. Compared with 85% of children who participated once, less than 25% with repeated experience gave the exact number of times they participated, although all knew they participated more than once. Children with repeated experience were asked additional temporal questions, and there were clear developmental differences. Older children were more able than younger children to judge relative order and temporal position of the four occurrences. They also demonstrated improved temporal memory for the first and last relative to the middle occurrences, while younger children did so only for the first. This is the first systematic demonstration of children's memory for temporal information after a repeated event. We discuss implications for theories of temporal memory development and the practical implications of asking children to provide temporal information. Copyright © 2015 John Wiley & Sons, Ltd.     

Consistently Inconsistent Working Memory Performance Among Children with ADHD: Evidence of Response Accuracy Variability (RAV)

Heterogeneity in cognitive performance, once regarded as noise, is now considered a causal mechanism or core deficit of ADHD and its related symptoms in most etiological models of the disorder. Previous research on cognitive performance variability has documented increased heterogeneity in response latencies using reaction time data. In contrast, variability in response accuracy remains understudied. The present study is the first to examine Response Accuracy Variability (RAV) among children with ADHD. Children with ADHD (N?=?54) and typically developing children (N?=?50) completed phonological working memory tasks with four set size conditions. RAV was calculated for each set size using the adjusted coefficient of variation (ζ). Results from a mixed model ANOVA indicated that children with ADHD evinced significantly greater variation in working memory performance relative to typically developing children when engaged in tasks within their cognitive capacity (i.e., set sizes 3 and 4), whereas all children exhibit similar, high levels of variability on tasks that exceeded their cognitive capacity (i.e., set sizes 5 and 6). Findings are aligned with the extant literature in documenting consistently inconsistent cognitive performance among children ADHD.

     

Laboratory Replication of Scientific Discovery Processes

Fourteen subjects were tape-recorded while they undertook to find a law to summarize numerical data they were given. The source of the data was not identified, nor were the variables labeled semantically. Unknown to the subjects, the data were measurements of the distances of the planets from the sun and the periods of their revolutions about it—equivalent to the data used by Johannes Kepler to discover his third law of planetary motion. Four of the 14 subjects discovered the same law as Kepler did (the period varies as the 3/2 power of the distance), and a fifth came very close to the answer. The subiects' protocols provide a detailed picture of the problem-solving searches they engaged in, which were mainly, but not exclusively, in the space of possible functions for fitting the data, and provide explanations as to why some succeeded and the others failed. The search heuristics used by the subjects are similar to those embodied in the BACON program, computer simulation of certain scientific discovery processes. The experiment demonstrates the feasibility of examining some of the processes of scientific discovery by recreating, in the laboratory, discovery situations of substantial historical relevance. It demonstrates also, that under conditions rather similar to those of the original discoverer, a law can be rediscovered by persons of ordinary intelligence (i.e., the intelligence needed for academic success in a good university). The data for the successful subjects reveal no “creative” processes in this kind of a discovery situation different from those that are regularly observed in all kinds of problem-solving settings.