Individual differences in working memory capacity and learning: Evidence from the serial reaction time task

High and low working memory (WM) capacity individuals performed the serial reaction time task under both incidental and intentional learning conditions to determine the role of WM capacity in the learning of sequential information. WM capacity differences emerged in conditions of intentional but not incidental learning, indicating that individual differences in WM capacity occur in tasks requiring some form of control, with little difference appearing on tasks that required relatively automatic processing. Furthermore, an index of learning was significantly related to a measure of general fluid intelligence under intentional conditions only. Thus, the degree of learning was significantly related to higher order cognition, but only when intentional processing was emphasized.     

Letter-by-letter reading: natural recovery and response to treatment

The present investigation provides a longitudinal study of an individual (RB) with acquired alexia following left posterior cerebral artery stroke. At initial testing, RB exhibited acquired alexia characterized by letter-by-letter (LBL) reading, mild anomic aphasia, and acquired agraphia. Repeated measures of reading accuracy and rate were collected for single words and text over the course of one year, along with probes of naming and spelling abilities. Improvements associated with natural recovery (i.e., without treatment) were documented up to the fourth month post onset, when text reading appeared to be relatively stable. Multiple oral reading (MOR) treatment was initiated at 22 weeks post-stroke, and additional improvements in reading rate and accuracy for text were documented that were greater than those expected on the basis of spontaneous recovery alone. Over the course of one year, reading reaction times for single words improved, and the word-length effect that is the hallmark of LBL reading diminished. RB's response to treatment supports the therapeutic value of MOR treatment to in LBL readers. His residual impairment of reading and spelling one-year post stroke raised the question as to whether further progress was impeded by degraded orthographic knowledge.     

Working memory span tasks: A methodological review and user’s guide

Working memory (WM) span tasks—and in particular, counting span, operation span, and reading span tasks—are widely used measures of WM capacity. Despite their popularity, however, there has never been a comprehensive analysis of the merits of WM span tasks as measurement tools. Here, we review the genesis of these tasks and discuss how and why they came to be so influential. In so doing, we address the reliability and validity of the tasks, and we consider more technical aspects of the tasks, such as optimal administration and scoring procedures. Finally, we discuss statistical and methodological techniques that have commonly been used in conjunction with WM span tasks, such as latent variable analysis and extreme-groups designs.     

An alternative to Cohen's standardized mean difference effect size: a robust parameter and confidence interval in the two independent groups case

The authors argue that a robust version of Cohen's effect size constructed by replacing population means with 20% trimmed means and the population standard deviation with the square root of a 20% Winsorized variance is a better measure of population separation than is Cohen's effect size. The authors investigated coverage probability for confidence intervals for the new effect size measure. The confidence intervals were constructed by using the noncentral t distribution and the percentile bootstrap. Over the range of distributions and effect sizes investigated in the study, coverage probability was better for the percentile bootstrap confidence interval.     

Argumentation, the Visual, and the Possibility of Refutation: An Exploration

Taking the possibility of visual argumentation seriously, this essay explores how refutation might proceed. We posit three ways in which images can refute and be refuted in a mixed-media environment: (1) dissection, in which an image is broken down discursively; (2) substitution, in which one image is replaced within a larger visual frame by a different image; and (3) transformation, in which an image is recontextualized in a new visual frame. These strategies are illustrated in an analysis of three American documentary films on abortion.     

TouchStat: A Monte Carlo program for calculating sequential touching probabilities

A growing number of child cognition researchers are using an object-manipulation, sequential-touching paradigm to explore young children’s conceptual abilities. Within this paradigm, it is essential to distinguish children’s intracategory touching sequences from those expected by chance. The sequentialtouching approach is congruent with a permutation testing model of statistical inference and is best modeled by sampled permutations as derived from Monte Carlo procedures. In this article, we introduce a computer program for generating Monte Carlo sequential-touching simulations. TouchStat permits users to determine their own specifications to simulate sequential touching to category exemplars across a wide range of task parameters. We also present Monte Carlo chance probabilities for the standard two-category, four-exemplar task, with sequences up to 30 touches long. Finally, we consider broader applications of the TouchStat program.     

Book Reviews

Pastoral Psychology -     

The Role of Counterfactual Thinking and Causal Attribution in Accident-Related Judgments

The effects of counterfactual thinking and causal attribution on accident-related judgments were investigated. Subjects read about a couple who died in an automobile accident where mutability of the outcome was varied. Mutability refers to the extent that a factual event can be mentally altered, with mutable outcomes more easily imagined otherwise than immutable outcomes. In comparison to the immutable scenario, participants reading the mutable scenario saw the accident as more avoidable, ascribed a greater causal role to the accident perpetrator, and perceived the perpetrator having more causal control over the couple's deaths. In addition to increased anger, a harsher financial penalty was levied against the accident perpetrator by participants in the mutable than in the immutable condition. Multiple regression analysis supported the efficacy of attribution theory to explain the affective and behavioral consequences of counterfactual thinking in accident-related judgments.     

Depressive Symptoms in African-American Women

This project examined the prevalence of depressive symptoms in an African-American female college student sample. Concordance rates between two of the most widely used psychometric instruments in clinical settings, the Minnesota Multiphasic Personality Inventory, revised edition (MMPI-2; Hathway & McKinley, 1967) and the Beck Depression Inventory (BDI; Beck, Ward, Mendelson, Mack, & Erbaugh, 1961), were examined. Results revealed that the MMPI-2 was a more conservative scale than the BDI in identifying depressive symptom levels. Both scales, however, identified 12% to 18% of the sample as experiencing severe symptoms. Results were interpreted in light of the stress model of depression. Participants who experienced many symptoms also had high levels of anxiety and passive coping styles. One significant covariate in this sample was mother's education level. Participants whose mothers had college experience had fewer depressive symptoms than their first-generation college-experience peers. Results were interpreted in light of the possible ways mothers inoculate their daughters from stressful environments because of their experiences and possible ways to use this process to assist first-generation college students.