The role of feedback and dot presentation format in younger and older adults’ number estimation

Numerosity estimation, the rapid assessment of the number of items in a visual scene, is historically inaccurate. We assessed whether providing feedback regarding the correct numerosity on either 0%, 50%, or 100% of the trials would affect younger and older adults’ estimation accuracy for randomized, clustered (i.e., groups of 3 or 7 dots), and stacked (i.e., column) dot formats. Participants provided estimates and confidence ratings in six blocks, each containing 48 trials (16 numerosities shown in each format). Feedback frequency was manipulated between participants during blocks 1–4; no feedback was provided during blocks 5 and 6, which contained old and new numerosities and previously estimated presentations rotated 90°. Estimation accuracy was age equivalent across blocks despite younger adults initially being more accurate than older adults. Feedback improved both age groups’ accuracy. Stacked presentations were most accurately estimated but were more likely to be over-estimated than clustered and randomized presentations. Older adults gave lower confidence ratings than younger adults despite both age groups showing increased confidence across blocks, for more structured presentation formats, and as feedback frequency increased. These results expand our understanding of the role of presentation format and feedback in producing age equivalence or age-related differences in numerosity estimation.     

Executive processing differences between learning-disabled,mildly retarded,and normal achieving children

This study examined possible executive processing differences between mildly retarded, learning-disabled, and normal achieving children. To this end, the groups were compared as to their ability to recall central and secondary words from base and elaborative sentences under conditions of high and low encoding effort. Executive processing was inferred from the children's ability to maintain optimal recall performance for central and secondary words. Groups were comparable in central recall, but differences in secondary recall occurred for the high- effort encoding condition. Qualitative differences related to the prioritizing of resources (as reflected in the correlation between central and secondary recall) and monitoring the transfer of information (as reflected from central and secondary recall insertions) were found between groups. The results were discussed in terms of an executive processing frame-work that views retarded children as suffering from inefficiencies related to the sharing of resources, whereas the learning-disabled children's inefficiencies were related to the discrimination of resources.The author is indebted to Karl Schemdli, Director of Special Education and Susan Swaim, Research Director, University of Northern Colorado Laboratory School, for their administration assistance in providing children for this study. The author is indebted to Dr. Jim Nicholes for his assistance in the data collection.     

Behavioral versus Behavioral and Pharmacological Treatment in ADHD Children Attending a Summer Treatment Program

As part of the behavioral treatment in the Multimodal Treatment Study of Children with ADHD (MTA), children participated in an intensive summer treatment program (STP). This study examined the differences between 57 children in the combined treatment (Comb) group, who were medicated, and 60 children in the behavioral treatment (Beh) group, who were unmedicated throughout the STP. Comb children were significantly better than Beh on 5 measures: rule following, good sportsmanship, peer negative nominations, and STP teacher posttreatment ratings of inattention/overactivity. Groups did not differ on any of the other 30 measures, and responded similarly to the STP over time. Comparisons to normative data revealed that Comb children were more likely to fall within the normative range on 6 measures. The differences between these results and the main MTA results, in which Comb was always superior to Beh, are discussed in terms of the relative intensity of combined treatments. The implications for future studies of pharmacological and behavioral treatment for ADHD are discussed.     

Suggestibility, social support, and memory for a novel experience in young children

This study examined 5- and 6-year-olds' suggestibility and interviewer demeanor as joint predictors of their memory for a novel experience. Session 1 consisted of children taking part in a novel laboratory event. Session 2 took place after approximately a 1-week delay and consisted of children completing both a memory test concerning what happened during the prior event and the Video Suggestibility Scale for Children (VSSC). During the second session, the interviewer behaved either supportively or nonsupportively. Greater acquiescence on the VSSC was associated with fewer correct responses to misleading questions about the laboratory event in the supportive and nonsupportive conditions and with more errors in response to specific questions in the nonsupportive condition. Results indicate that individual differences in children's suggestibility are related to the accuracy of their memory for separate events, although some of these relations may vary depending on the context in which children are interviewed.