Recent Publications

(*Denotes graduate-student advisee)

 

Basic Memory Work

 

Bugg*, J. M., DeLosh, E. L., & McDaniel, M. A. (2008). Improving students’ study habits by demonstrating the mnemonic benefits of semantic processing. Teaching of Psychology, 35, 96-98. This article describes an in-class exercise that illustrates the advantage of semantic over nonsemantic study habits. The exercise includes a survey of students’ current study strategies, followed by the presentation of an abbreviated version of Craik and Tulving’s (1975) classic levels-of-processing experiment. We observed significant benefits of semantic processing over nonsemantic processing, and this result motivated an in-depth discussion regarding the limitations of students’ intuitions about effective study strategies and methods for improving current strategies. The brief exercise changed students’ intended strategies for future studying and helped students learn the concept of semantic processing.

 

Carpenter*, S. K., & DeLosh, E. L. (2005). Application of the testing and spacing effects to name learning. Applied Cognitive Psychology, 19, 619-636. Four experiments investigated the effects of testing and spacing on the learning of face-name stimulus-response pairs. Experiments 1a and 1b compared the recall of names following intervening tests versus additional study opportunities and found that testing produced better retention of names. Experiments 2 and 3 explored the effects of repeated tests versus study for massed, uniform, or expanded spacing intervals. Tested names were better retained than studied names, spaced names were better retained than massed names, and memory was best for items tested at spaced intervals. Contrary to past findings, expanded schedules did not yield better memory than uniform schedules in either experiment. Theoretical implications for the testing and spacing effects are discussed, along with effective name-learning techniques based on these principles.

Carpenter*, S. K., & DeLosh, E. L. (2006). Impoverished cue support enhances subsequent retention: Support for the elaborative retrieval explanation of the testing effect. Memory & Cognition, 34, 268-276. In three experiments, we investigated the role of transfer-appropriate processing and elaborative processing in the testing effect. In Experiment 1, we examined whether the magnitude of the testing effect reflects the match between intervening and final tests by factorially manipulating the type of intervening and final tests. Retention was not enhanced for matching, relative to mismatching, intervening and final tests, contrary to the transfer-appropriate–processing view. In Experiment 2, we examined final retention as a function of the number of cues needed to retrieve items on intervening cued recall tests. In this case, fewer retrieval cues were associated with better memory on the final test. Experiment 3 replicated the findings of Experiment 2 while controlling for individual item difficulty and directly manipulating the number of cues present. These findings suggest that an intervening test may be most beneficial to final retention when it provides more potential for elaborative processing.

 

Merritt*, P. S., DeLosh, E. L., & McDaniel, M. A. (2006). Effects of word frequency on individual-item and serial-order retention: Tests of the order-encoding view. Memory & Cognition, 34, 1615-1627. The order encoding view of the word-frequency effect proposed that low-frequency (LF) items attract more attention to the encoding of individual-item information than high-frequency (HF) items, but at the expense of order encoding (DeLosh & McDaniel, 1996). When combined with the assumption that free recall of unrelated words is organized according to their original order of presentation, this view explains the finding that HF words are better recalled than LF words in pure lists, but in mixed lists recall is better for LF words. The present study confirmed that in mixed lists order memory becomes equivalent for HF and LF words, and that the predicted pattern of order memory and recall holds for incidental order-encoding conditions, for longer lists than used in previous experiments, and for lists with minimal inter-item associativity. Moreover, recall from HF lists declined but recall from LF lists improved in related-word lists relative to unrelated-word lists, reversing the usual pure-list free-recall advantage for HF words. These results were uniquely predicted by the order-encoding account and favor this view over accessibility, inter-item association, and cueing effectiveness explanations of the word-frequency effect.

 

Aging and Cognition Papers

 

Bugg*, J. M., DeLosh, E. L., & Clegg, B. A. (2006). Physical activity moderates time-of-day differences in older adults’ working memory performance. Experimental Aging Research, 32, 431-446. Based on a synthesis of the literature on time of day and physical fitness effects on cognition, the current study examined whether physical activity moderated time-of-day differences in older adults’ performance on a working memory task. Sedentary older adults’ working memory performance declined significantly from morning to evening, whereas more active older adults performed similarly across the day. This interaction did not extend to performance on a simple reaction time task. A novel explanation based on the selective effect of mental fatigue on executive control processes is proposed.

 

Bugg*, J. M., DeLosh, E. L., Davalos, D. B., & Davis, H. P. (2007). Age differences in Stroop interference: Contributions of general slowing and task-specific deficits. Aging, Neuropsychology, and Cognition, 14, 155-167. This study examined the contributions of general slowing and task-specific deficits to age-related changes in Stroop interference. Nine hundred thirty-eight participants aged 20 to 89 years completed an abbreviated Stroop color-naming task and a subset of 281 participants also completed card-sorting, simple reaction time, and choice reaction time tasks. Age-related increases in incongruent color-naming latency and card-sorting perseverative errors were observed. Hierarchical regression analyses showed that the processing speed measures accounted for significant variance on both dependent measures, but that there was also a significant residual effect of age. An additional regression analysis showed that some of the variance in incongruent color-naming, after controlling for processing speed, was shared with the variance in perseverative errors. Overall, findings suggest that the age difference in Stroop interference is partially attributable to general slowing, but is also attributable to age-related changes in task-specific processes such as inhibitory control.

 

Bugg*, J. M., Zook*, N. A., DeLosh, E. L., Davalos, D. B., & Davis, H. P. (2006). Age differences in fluid intelligence: Contributions of general slowing and frontal decline. Brain and Cognition, 62, 9-16. The current study examined the contributions of general slowing and frontal decline to age differences in fluid intelligence. Participants aged 20–89 years completed Block Design, Matrix Reasoning, simple reaction time, choice reaction time, Wisconsin Card Sorting, and Tower of London tasks. Age-related declines in fluid intelligence, speed of processing, and frontal function were observed. Hierarchical regression analyses showed that the processing speed and frontal function measures accounted for significant variance in fluid intelligence performance, but there was also a residual effect of age after controlling for each variable individually as well as both variables. An additional analysis showed that the variance in fluid intelligence that was attributable to processing speed was not fully shared with the variance attributable to frontal function. These Findings suggest that the age-related decline in fluid intelligence is due to general slowing and frontal decline, as well as other unidentified factors.

 

Edward L. DeLosh, Ph.D.