David J. Therriault

A latent variable analysis of working memory capacity, short-term memory capacity, processing speed, and general fluid intelligence

Significant relationships exist between general fluid intelligence and each of the following constructs: short-term memory capacity, working memory capacity (WMC), and processing speed. However, the interrelationship among all four constructs has not been investigated. Multiple measures of each of these constructs were obtained from 120 healthy young adults. Structural equation modeling was then performed to determine which construct served as the best predictor of general fluid intelligence. The results suggest that WMC, but not short-term memory capacity or processing speed, is a good predictor of general fluid intelligence in young adults. Possible mechanisms underlying the link between WMC and general fluid intelligence are discussed. D 2002 Elsevier Science Inc. All rights reserved.

The role of color diagnosticity in object recognition and representation

The role of color diagnosticity in object recognition and representation was assessed in three Experiments. In Experiment 1a, participants named pictured objects that were strongly associated with a particular color (e.g., pumpkin and orange). Stimuli were presented in a congruent color, incongruent color, or grayscale. Results indicated that congruent color facilitated naming time, incongruent color impeded naming time, and naming times for grayscale items were situated between the congruent and incongruent conditions. Experiment 1b replicated Experiment 1a using a verification task. Experiment 2 employed a picture rebus paradigm in which participants read sentences one word at a time that included pictures of color diagnostic objects (i.e., pictures were substituted for critical nouns). Results indicated that the “reading” times of these pictures mirrored the pattern found in Experiment 1. In Experiment 3, an attempt was made to override color diagnosticity using linguistic context (e.g., a pumpkin was described as painted green). Linguistic context did not override color diagnosticity. Collectively, the results demonstrate that color information is regularly utilized in object recognition and representation for highly color diagnostic items.

Assessing the influence of dimensional focus during situation model construction.

According to Zwaan, Langston, and Graesser’s (1995) event-indexing model, when comprehending text, readers monitor changes in a series of critical dimensions: space, time, protagonist, causality, and intentionality. In this study, the influence of dimensional focus was assessed during situation-model construction. Participants read narratives and were instructed to specifically monitor a single dimension while their sentence reading times were recorded. Critical sentence reading times were then analyzed for all shift types. Results support the general prediction that at least the time and protagonist dimensions are resistant to task demands, demonstrating that comprehenders routinely perform dimensional updating processes that are context independent. These results are discussed in the context of the event-indexing model.

Verb aspect and perceptual simulations.

Two experiments investigate the influence of verb aspect on situation representations. The results demonstrate that comprehenders use verb aspect as a cue to regulate the activation of ongoing simulations of situations over time. Experiment 1 measured word-by-word reading as well as sensibility judgements on sentences in which a target object word had been replaced by a picture. For the past imperfective sentences, participants were faster to process the picture, the two words following the picture, and the sensibility judgements when objects were pictured in use rather than not in use. However, this in-use facilitation was limited to processing of the picture for the past perfect sentences. Experiment 2 served as a control to ensure that the use effect and its interaction with verb aspect were a result of contextual manipulations rather than surface features of the pictures themselves. The results are interpreted within the framework of perceptual simulations during language comprehension.

Repetition Effects From Paraphrased Text: Evidence for an Integrated Representation Model of Text Representation

The effect of text repetition on reading performance and memory was examined. Participants read a set of short passages, each twice in succession. The second reading was either the same text or a paraphrased version of the original text. Both same texts and paraphrased texts were read faster during the second reading, but the repetition effect was slightly smaller for paraphrased texts. This was reflected by changes in global measures of reading performance (e.g., reduced reading time) and by reduced fixation durations on individual words. The results are consistent with a model of text repetition effects in which wording is represented in an abstract, context-independent manner, whereas the situation described by the text is represented in an episodic, context-dependent manner

Classifying retrieval strategies as a function of working memory.

Strategy selection may help explain performance differences between individuals with high working memory capacity (HWMs) and low working memory capacity (LWMs) (Budd, Whitney, & Turley, (Memory & Cognition, 23, 735–748 1995); Cokely, Kelley, & Gilchrist, (Psychonomic Bulletin & Review, 13, 991–997 2006). We compared the independent and spontaneous strategy use of HWMs and LWMs during a category fluency (retrieval) task that required participants to retrieve animal names. HWMs were more successful at the fluency task under normal conditions, but under increased cognitive load, there were no WM-related performance differences. One strategy (i.e., retrieving animals according to their scientific classification) significantly aided performance, irrespective of cognitive load. Under normal conditions, HWMs were more likely to use the effective strategy; however, under load, WM did not predict strategy use. Use of the classification strategy was more strongly related to retrieval performance than was WM. These results suggest that retrieval strategy use is related to WM capacity, and that employing a successful strategy may make up for WM disadvantages during a demanding retrieval task.

Moving beyond Formulas and Fixations: Solving Open-Ended Engineering Problems.

Open-ended problem solving is a central skill in engineering practice; consequently, it is imperative for engineering students to develop expertise in solving these types of problems. The complexity of open-ended problems requires a unique set of skills. The purpose of this qualitative study was to investigate the approaches used by engineering students when solving an open-ended engineering problem. A think-aloud method was used to collect data about the problem-solving approaches of eight materials engineering students. Through the use of script analysis three approaches to solving the problem were identified, which were consistent with the Reflective Judgment Model of epistemic development. Students who used a linear, systematic approach were most successful at solving the problem. Less successful students were overwhelmed by its open-endedness and/or became fixated on a single aspect of the problem. These results point to a need to develop open-ended problem-solving skills throughout the engineering curriculum.

Reconceptualizing and decentering think-aloud methodology in qualitative research

Most applications of think-aloud protocols have been conducted from theoretical perspectives that prioritize knowledge that is predictable and controlled by the researchers. In this article, we present an augmented form of the think-aloud method in which we aim to gain situated and participant-generated knowledge. The context for our study is examination of the problem-solving processes used by engineering students. We illustrate how our adaptation of traditional think–aloud protocols provides insights into participants’ thoughts and beliefs and how such think-alouds can increase social scientists’ understandings of complex phenomena such as learning or problem solving. In contrast to a typical focus on researcher-defined processes or an analysis of the products generated by students, our approach to think-aloud utilizes think-aloud procedures in combination with follow-up interviews to expand participants’ perspectives and investigate their experiences more deeply.

Processing and Representing Temporal Information in Narrative Text

Abstract According to current theories in discourse research, readers monitor a series of 5 situational dimensions during narrative comprehension (Zwaan, Langston, & Graesser, 1995; Zwaan & Radvansky, 1998). These dimensions are time (e.g., the order of events), space (e.g., locations), protagonist (e.g., main character actions), causality (e.g., how one event influences another event), and intentionality (e.g., goals). These experiments were designed to further explore how readers process and represent time (duration) in situation-model construction. In 3 experiments, we examined how duration-related inconsistencies influenced processing time and processing strategies. Results indicate that readers routinely monitor the duration of events and detect temporal inconsistencies even when temporal information is implicitly presented. This provides evidence for the representation of duration information in situation models.

Multiple Science Text Processing: Building Comprehension Skills for College Student Readers

The goal of this investigation was to determine which reading instruction improves multiple science text comprehension for college student readers. The authors first identified the cognitive processing strategies that are predictive of multiple science text comprehension (Study 1) and then used what they learned to experimentally test the effectiveness of explicit pre-reading instructions (Study 2). Study 1 showed that self-explaining was positively related to comprehension tasks. Study 2 showed that explicitly instructing participants to self-explain while reading multiple science texts enhanced comprehension test performance. These results showed that self-explanation during reading is a successful strategy for enhancing multiple science text comprehension.