Multifactorial assessment of reading disability: identifying the best predictors

A multifactorial diagnostic assessment battery was evaluated using data obtained from 105 reading-disabled children and their matched controls (total N = 210). A stepwise discriminant function analysis selected five nonreading measures from among 16 as the best diagnostic predictors of reading disability. These measures included WISC-R Information and Digit Span, self-reported family histories of reading problems, and tests of symbol-processing speed and letter fluency.     

The Social Psychology of Caregiving: Physical and Psychological Costs of Providing Support to the Disabled1

The emphasis of much of the existing research on social support-health relationships has been on the availability and impact of support on the recipient, but social psychologists have paid little attention to the costs to the caregiver of providing that support. In an earlier study (Schulz & Decker, 1985), we found that the long-term coping of individuals experiencing chronic disability as a result of spinal-cord injury was facilitated by the availability of a primary support person, or caregiver. In this study we examined the determinants of well-being of the primary caregiver of the middle-aged and elderly spinal-cord-injured persons. Psychological well-being, life satisfaction, and depression were the dependent measures. The availability of social support, social contact, and feelings of control over one's life were important determinants of caregiver well-being, even after controlling for health and income. In addition, the amount of time spent each day assisting the disabled person was a strong independent correlate of depression, and the extent to which the caregiver felt burdened by the victim was significantly and negatively related to life satisfaction. These results are discussed in the context of a comprehensive stress-coping model. Since data were available from both disabled individuals and their primary support persons, we had the unique opportunity to compare the perspectives of both those giving and receiving daily care. We found no relationship in levels of psychological well-being and depression reported by the disabled person and caregiver; however, caregivers attributed to the victims affective levels similar to their own.     

Regression analyses as a tool for studying reading processes: Comment on Just and Carpenters eye fixation theory

Just and Carpenter (1980) presented a theory of reading based on eye fixations wherein their “psycholinguistic” variables accounted for 72% of the variance in word gaze durations. This comment raises some statistical and theoretical problems with their use of simultaneous regression analysis of gaze duration measures and with the resulting theory of reading. A major problem was the confounding of perceptual with psycholinguistic factors. New eye fixation data are presented to support these criticisms. Analysis of fixations within words revealed that most gaze duration variance was contributed by number of fixations rather than by fixation duration.     

Simultaneous cognitive operations in working memory after dual-task practice

The authors tested the hypothesis that with adequate practice, people can execute 2 cognitive operations in working memory simultaneously. In Experiment 1, 6 students practiced updating 2 items in working memory through 2 sequences of operations (1 numerical, 1 spatial). In different blocks, imperative stimuli for the 2 sequences of operations were presented either simultaneously or sequentially. Initially, most participants experienced substantial dual-task costs. After 24 sessions of practice, operation latencies for simultaneous presentation were equal to the maximum of times for the 2 operations in the sequential condition, suggesting perfect timesharing. Experiment 2 showed that a reduction of dual-task costs requires practice on the combination of the 2 updating tasks, not just practice on each individual task. Hence, the reduction of dual-task costs cannot be explained by shortening or automatization of individual operations.     

Age differences in working memory— The roles of storage and selective access

Twenty-four young (23 years) and 24 old (71 years) adults performed arithmetic tasks with working memory loads ranging from 1 to 4. Age groups were equivalent in mean accuracy and speed of arithmetic operations under minimal working memory load, but old adults were slower than young with memory demands >1. Access to a new object in working memory as the basis of computation required additional time. This object-switching cost increased with increases in memory demand, but was unaffected by age, indicating that old adults have no deficit in selective access to working memory.     

Differential effects of cue changes and task changes on task-set selection costs

A task-switching paradigm with a 2:1 mapping between cues and tasks was used to separate cue-switching processes (indexed through pure cue-switch costs) from actual task-switching processes (indexed through additional costs in case of cue and task changes). A large portion of total switch costs was due to cue changes (Experiments 1 and 2), and cue-switch costs but not task-switch costs were sensitive to effects of practice (Experiment 1) and preparation (Experiment 2). In contrast, task-switch costs were particularly sensitive to response-priming effects (Experiments 1 and 2) and task-set inhibition (Experiment 3). Results suggest two processing stages relevant during task-set selection: cue-driven retrieval of task rules from long-term memory and the automatic application of rules to a particular stimulus situation.     

Lexical and sublexical semantic preview benefits in Chinese reading

Semantic processing from parafoveal words is an elusive phenomenon in alphabetic languages, but it has been demonstrated only for a restricted set of noncompound Chinese characters. Using the gaze-contingent boundary paradigm, this experiment examined whether parafoveal lexical and sublexical semantic information was extracted from compound preview characters. Results generalized parafoveal semantic processing to this representative set of Chinese characters and extended the parafoveal processing to radical (sublexical) level semantic information extraction. Implications for notions of parafoveal information extraction during Chinese reading are discussed.     

On the ambiguity of interaction and nonlinear main effects in a regime of dependent covariates

The analysis of large experimental datasets frequently reveals significant interactions that are difficult to interpret within the theoretical framework guiding the research. Some of these interactions actually arise from the presence of unspecified nonlinear main effects and statistically dependent covariates in the statistical model. Importantly, such nonlinear main effects may be compatible (or, at least, not incompatible) with the current theoretical framework. In the present literature, this issue has only been studied in terms of correlated (linearly dependent) covariates. Here we generalize to nonlinear main effects (i.e., main effects of arbitrary shape) and dependent covariates. We propose a novel nonparametric method to test for ambiguous interactions where present parametric methods fail. We illustrate the method with a set of simulations and with reanalyses (a) of effects of parental education on their children’s educational expectations and (b) of effects of word properties on fixation locations during reading of natural sentences, specifically of effects of length and morphological complexity of the word to be fixated next. The resolution of such ambiguities facilitates theoretical progress.