Courtney C. Dornburg

Age differences in veridical and false recall are not inevitable: The role of frontal lobe function

The relationship of neuropsychological measures of frontal lobe function to age differences in false recall was assessed using the Deese/Roediger-McDermott associative false memory paradigm (Deese, 1959; Roediger & McDermott, 1995). As other studies have found, older adults were less likely to correctly recall studied items and more likely to falsely recall highly related but nonpresented items than were younger adults. When older adults were divided based on a composite measure of frontal lobe functioning, this age difference was found only for low frontal lobe functioning individuals. High frontal lobe functioning older adults and young adults had equivalent levels of false recall, as well as equivalent levels of veridical recall. These results suggest that age differences in memory may be due to declines in frontal lobe function. More important, our findings indicate that declines in veridical recall and increases in false recall are not an inevitable consequence of aging.

Disentangling encoding versus retrieval explanations of the bizarreness effect: implications for distinctiveness.

Recall effects attributed to distinctiveness have been explained by both encoding and retrieval accounts. Resolution of this theoretical controversy has been clouded because the typical methodology confounds the encoding and retrieval contexts. Using bizarre and common sentences as materials, we introduce a paradigm that decouples the nature of the encoding context (mixed vs. unmixed lists of items) from the retrieval set (mixed vs. unmixed retrieval sets). Experiment 1 presented unmixed lists for study, and Experiment 2 presented mixed lists for study. In both experiments, significant bizarreness effects were obtained in free recall when the retrieval set intermixed items but not when the retrieval set consisted of only one item type. Also, Experiment 1, using a repeated testing procedure, did not reveal evidence for more extensive encoding of bizarre sentences than of common sentences. The results support the idea that retrieval dynamics primarily mediate the bizarreness effect, and perhaps more generally, distinctiveness effects.

The Influence of Distinctive Processing Manipulations on Older Adults' False Memory

ABSTRACT Covertly generating item-specific characteristics for each studied word from DRM (Deese–Roediger–McDermott) lists decreases false memory in young adults. The typical interpretation of this finding is that item-specific characteristics act as additional unique source information bound to each studied item at encoding, and at retrieval young adults can use the absence of this type of information to reject non-presented associated words that might otherwise be falsely remembered. In two experiments, we examined whether healthy older adults could use this strategy to reduce their false memories in the DRM paradigm. In Experiment 1, low frontal lobe functioning was associated with increased false memory in the item-specific strategy condition. Experiment 2 found more memory intrusions under item-specific encoding and the same amount of false memory in auditory and visual presentation conditions, i.e., no modality effect, even with 8 s of encoding time. Both findings are consistent with impaired distinctive processing by older adults.

Age-Related Deficits in Reality Monitoring of Action Memories

The authors describe 3 theoretical accounts of age-related increases in falsely remembering that imagined actions were performed (A. K. Thomas & J. B. Bulevich, 2006). To investigate these accounts and further explore age-related changes in reality monitoring of action memories, the authors used a new paradigm in which actions were (a) imagined only, (b) actually performed, or (c) both imagined and performed. Older adults were more likely than younger adults to misremember the source of imagined-only actions, with older adults more often specifying that the action was imagined and also that it was performed. For both age groups, illusions that the actions were only performed decreased as repetitions of the imagined-only events increased. These patterns suggest that both older and younger adults use qualitative characteristics when making reality-monitoring judgments and that repeated imagination produces richer records of both sensory details and cognitive operations. However, sensory information derived from imagination appears to be more similar to that derived from performance for older adults than for younger adults.

Improving Extreme-Scale Problem Solving: Assessing Electronic Brainstorming Effectiveness in an Industrial Setting

Objective: An experiment was conducted to compare the effectiveness of individual versus group electronic brainstorming to address difficult, real-world challenges. Background: Although industrial reliance on electronic communications has become ubiquitous, empirical and theoretical understanding of the bounds of its effectiveness have been limited. Previous research using short-term laboratory experiments have engaged small groups of students in answering questions irrelevant to an industrial setting. The present experiment extends current findings beyond the laboratory to larger groups of real-world employees addressing organization-relevant challenges during the course of 4 days. Methods: Employees and contractors at a national laboratory participated, either in a group setting or individually, in an electronic brainstorm to pose solutions to a real-world problem. Results: The data demonstrate that (for this design) individuals perform at least as well as groups in producing quantity of electronic ideas, regardless of brainstorming duration. However, when judged with respect to quality along three dimensions (originality, feasibility, and effectiveness), the individuals significantly (p < .05) outperformed the group. Conclusion: When quality is used to benchmark success, these data indicate that work-relevant challenges are better solved by aggregating electronic individual responses rather than by electronically convening a group. Application: This research suggests that industrial reliance on electronic problem-solving groups should be tempered, and large nominal groups may be more appropriate corporate problem-solving vehicles.

Working memory load as a novel tool for evaluating visual analytics

The current visual analytics literature highlights design and evaluation processes that are highly variable and situation dependent, which raises at least two broad challenges. First, lack of a standardized evaluation criterion leads to costly re-designs for each task and specific user community. Second, this inadequacy in criterion validation raises significant uncertainty regarding visualization outputs and their related decisions, which may be especially troubling in high consequence environments like those of the Intelligence Community. As an attempt to standardize the “apples and oranges” of the extant situation, we propose the creation of standardized evaluation tools using general principles of human cognition. Theoretically, visual analytics enables the user to see information in a way that should attenuate the users memory load and increase the users task-available cognitive resources. By using general cognitive abilities like available working memory resources as our dependent measures, we propose to develop standardized evaluative capabilities that can be generalized across contexts, tasks, and user communities.

Utilizing pathfinder in the design of an intranet website

Usability analyses of the Homepage Categories and Sub-categories at Sandia National Laboratories were undertaken to identify potential improvement opportunities to the current architecture. Through traditional card sorting methods, as well as a novel implementation of Pathfinder analysis, a novel re-structuring and minimal nomenclature changes are suggested for future user testing. Additionally, the study finds Pathfinder analysis a useful addition to traditional usability methods and suggests related methodological research opportunities.

Evaluating Information Visualizations with Working Memory Metrics

Information visualization tools are being promoted to aid decision support. These tools assist in the analysis and comprehension of ambiguous and conflicting data sets. Formal evaluations are necessary to demonstrate the effectiveness of visualization tools, yet conducting these studies is difficult. Objective metrics that allow designers to compare the amount of work required for users to operate a particular interface are lacking. This in turn makes it difficult to compare workload across different interfaces, which is problematic for complicated information visualization and visual analytics packages. We believe that measures of working memory load can provide a more objective and consistent way of assessing visualizations and user interfaces across a range of applications. We present initial findings from a study using measures of working memory load to compare the usability of two graph representations.

Individual and Group Electronic Brainstorming in an Industrial Setting

An experiment was conducted comparing the effectiveness of individual versus group electronic brainstorming in addressing real-world “wickedly difficult” challenges. Previous laboratory research has engaged small groups of students in answering questions irrelevant to an industrial setting. The current experiment extended this research to larger, real-world employee groups engaged in addressing organization-relevant challenges. Within the present experiment, the data demonstrated that individuals performed at least as well as groups in terms of number of ideas produced and significantly (p<.02) outperformed groups in terms of the quality of those ideas (as measured along the dimensions of originality, feasibility, and effectiveness).

Improving human effectiveness for extreme-scale problem solving : final report (assessing the effectiveness of electronic brainstorming in an industrial setting).

An experiment was conducted comparing the effectiveness of individual versus group electronic brainstorming in order to address difficult, real world challenges. While industrial reliance on electronic communications has become ubiquitous, empirical and theoretical understanding of the bounds of its effectiveness have been limited. Previous research using short-term, laboratory experiments have engaged small groups of students in answering questions irrelevant to an industrial setting. The current experiment extends current findings beyond the laboratory to larger groups of real-world employees addressing organization-relevant challenges over the course of four days. Findings are twofold. First, the data demonstrate that (for this design) individuals perform at least as well as groups in producing quantity of electronic ideas, regardless of brainstorming duration. However, when judged with respect to quality along three dimensions (originality, feasibility, and effectiveness), the individuals significantly (p<0.05) out performed the group working together. The theoretical and applied (e.g., cost effectiveness) implications of this finding are discussed. Second, the current experiment yielded several viable solutions to the wickedly difficult problem that was posed.