Amy M. Shapiro

How Including Prior Knowledge As a Subject Variable May Change Outcomes of Learning Research

Prior knowledge has a marked effect on learning outcomes. Researchers typically rely on a number of methodologies to control for that factor in learning research, including the use of fictional stimuli and domain-novice subjects. The experiments reported here demonstrate that such methodological controls may be insufficient. In Experiment 1, students read texts about fictional places and events. In Experiment 2, novice students in a cognition course were asked to read several advanced texts. In both experiments, prior knowledge accounted for a large portion of the subjects’ posttest performance. The data demonstrate that methodological approaches intended to control for prior knowledge may be insufficient to prevent that variable from influencing learning outcomes. Thus researchers are urged to include measures of prior knowledge in their analyses.

Forgetting of verbatim information in discourse

In tree experiments, the causes of forgetting of verbatim information in discourse were investigated. In experiment 1, we tested the view that the surface form of a sentence decays when linguistic elements are integrated into larger discourse structures. Contrary to such a view, the results showed that when text could be integrated, both content and verbatim memory improved. In Experiment 2, we examined the possibility that task instructions could influence the level of memory for exact wording and content. The results showed that although task did influence the amount of verbatim memory, it did not affect memory for content. Experiment 3 was an investigation of the degree to which subjects would spontaneously encode surface information on the basis of the social interactiveness of the sentences. Past research has shown that verbatim memory for insults, jokes, and other personal utterances is quite good. In this experiment, identical sentences were tested in texts that had high versus low interactiveness. Verbatim memory was much higher for the same sentences in the highly interactive context. A pragmatic account of verbatim memory is given to explain how content and instructions influence the encoding of surface form.

Multimedia and Hypermedia Solutions for Promoting Metacognitive Engagement, Coherence, and Learning:

Users of educational hypertext are faced with the challenge of creating meaning both within and between texts. Cohesion is an important factor contributing to whether a reader is able to capture meaning and comprehend text. When readers are required to fill in conceptual gaps in text, comprehension can fail if they do not have sufficient knowledge. Cohesion helps low-knowledge readers to create a more coherent mental representation of the text. However, text that is too cohesive can inhibit active processing, and thus reduce coherence for more knowledgeable readers. Similar patterns have been found for hypertext, which requires readers to create coherence between multiple electronic texts. Domain novices are in greater need of explicit pointers to important links between documents and gain from having less control over system navigation. Domain experts are in less need of scaffolding within the system. We discuss the use of a multimedia reading strategy training program to help low-knowledge readers better understand less cohesive text. Finally, we discuss four principles to guide hypertext development geared toward improving coherence and metacognitive engagement.

An Investigation of the Cognitive Processes Underlying the Keyword Method of Foreign Vocabulary Learning.

The Keyword Method (KWM) of vocabulary learning is a mnemonic method designed to help students learn foreign vocabulary. It has been shown to be effective over several other memorization strategies. The present experiment was designed to explore the cognition underlying the effectiveness of the KWM. Specifically, both the degree of cognitive engagement with the method and visual encoding were examined as possible sources. Subjects were tested in a 2 (imagery level)×2 (processing strategy) mixed design. Each subject was asked to memorize 30 Latin vocabulary words, divided evenly among high- and low-imagery value words. Subjects were either provided with both keywords and interactions (the Given condition) or instructions to generate their own keywords and interactions (the Self-Generated condition). Retention was tested in both immediate and delayed post-tests. Results revealed a strong effect of imagery level in both post-tests. No significant main effect of processing strategy or interactions between imagery and processing were observed in either post-test. Results indicate that the KWM is effective because it provides a meaningful visual image upon which to base memory for a new word’s meaning. They suggest that there is some flexibility in how the KWM is used.

The Use of Latent Semantic Analysis as a Tool for the Quantitative Assessment of Understanding and Knowledge

Latent Semantic Analysis (LSA) is a statistical model of word usage that has been used for a variety of applications. One of these applications is the quantitative assessment of the semantic content within written text. While the technology has been successful in correlating with the qualitative ratings of human experts, it is unclear what aspect of knowledge is being reflected in an LSA output. The two experiments presented here were designed to address this general question. We were particularly interested in whether an LSA analysis more accurately reflects the factual or conceptual knowledge contained in written material. Experiment 1 explored this issue by comparing LSA analyses of essays to human-generated scores. It also compared the LSA output to several measures of conceptual structure. Experiment 2 correlated LSA analyses of transcribed recall protocols with a series of comprehension measures that were designed to vary in the degree to which they reflect conceptual or factual knowledge. We found compelling evidence that LSA analyses are a stronger reflection of the text-based knowledge represented by essays and recall protocols than conceptual knowledge. Both studies also explored a methodological issue pertaining to the use of LSA. Specifically, does LSA have to be “trained” in the particular content area of the text to be analyzed? This question was addressed by running multiple LSA analyses, each performed with differing “semantic spaces” created through training in domain specific or general content areas. We found that LSA performed best when trained in a content area specific to the material to be analyzed. These results are discussed with respect to the application of LSA analyses in the classroom and laboratory.

Priming correct information reduces the misinformation effect

The misinformation effect is a well-established phenomenon in the false memory literature, although the mechanisms that underlie it are debated. In the present study, we explored one aspect of the controversy, the fate of the original memory. We began from an activation-based view of memory, capitalizing on the well-understood processes of associative priming and spreading activation, to test the hypothesis that true and suggested information can coexist in memory. After exposure to misinformation, participants were unknowingly primed with associates of either the true or a suggested item. Misled participants who were primed for the true item performed better on a final memory test than did misled participants primed for neutral information. The results indicated that true and suggested information coexist and that retrieval is influenced by each concept’s activation level at test. Implications for theories of the misinformation effect were discussed.

Repeated recall as an intervention to improve memory performance in heart failure patients

Background: Up to 50% of heart failure patients demonstrate aspects of cognitive impairment, including memory deficit. Novel interventions are needed to address memory deficit among heart failure patients. Aim: The goal of this study was to evaluate the testing effect as an intervention to improve memory performance in heart failure patients. Methods: This was a randomized controlled clinical trial (N=84) comparing the memory performance of heart failure patients with and without mild cognitive impairment after a repeated testing intervention. Memory performance was measured by verbal word pair associates recall scores, between attention control and experimental subjects. Results: Patients had a mean age of 71.7 ± 13.3 years and similar baseline memory (immediate p=.79 and delayed p=.47). Overall, there were no significant differences in memory between experimental and control subjects, respectively (67.2±18.87 vs. 61.9±22.3, verbal word pair associates, t = −1.179, p=.24). In the final hierarchical regression model, age (p=.018) and education (p=.006) were significant predictors of memory performance, with the intervention approaching significance (p=.079). Conclusions: Although not statistically significant, the intervention group reported better memory. Age and education continue to be significant contributors to memory performance in the heart failure population. Continued development of interventions to improve memory performance in heart failure patients is indicated.