Memory lapses during a pandemic: Differential associations between COVID-stress and daily memory lapses?

The policies related to COVID-19 pandemic such as stay at home orders and social distancing increased daily stress and associated impairments in mental health. This study examines the association between COVID-related stress and cognitive functioning by examining two different types of daily memory lapses, those related to prospective memory (i.e., memory for future plans) and retrospective memory (i.e., memory for past information) as well as the perceived emotional and functional consequences of daily memory problems. As part of a larger study, 58 adults (18 men; 22 ± 3 years) completed a web-based version of the daily inventory of stressful events including stress related to COVID-19 and positive/negative affect for eight consecutive days between 8 September 2020 and 11 November 2020. Findings showed that prospective lapses were positively correlated with COVID-19 stressors (r = 0.41, p = 0.002). At the within-person level, daily COVID-19 stressors were significantly associated with the number of prospective lapses (b = 0.088, SE = 0.040). COVID-19-related stressors were not significantly related to retrospective lapses (all ps > 0.05). Our findings suggested that more daily COVID-19 stressors were related to greater numbers of prospective lapses in daily life even among healthy younger adults. Thus, future research should address long term relations of COVID-19 stress and cognitive functioning in addition to the specific cognitive impairments related to COVID-19 infection.     

A general rotation criterion and its use in orthogonal rotation

Measures of test parsimony and factor parsimony are defined. Minimizing their weighted sum produces a general rotation criterion for either oblique or orthogonal rotation. The quartimax, varimax and equamax criteria are special cases of the expression. Two new criteria are developed. One of these, the parsimax criterion, apparently gives excellent results. It is argued that one of the most important factors bearing on the choice of a rotation criterion for a particular problem is the amount of information available on the number of factors that should be rotated. This research was supported by the National Research Council of Canada research grant 291-13 to Dr. G. A. Ferguson.     

The influence of perceptual and motor factors on bimanual coordination in a polyrhythmic tapping task

Summary In this study the role of perceptual and motor factors on the motor organization (integrated versus parallel) adopted by musically skilled and unskilled subjects in a polyrhythmic tapping task was investigated. Subjects tapped a 3:2 polyrhythm to match the timing of two isochronous tone trains, one tone train for each hand. Perceptual factors were examined by the manipulation of the frequency difference between the tone trains to produce either an integrated or a streamed percept. Motor factors were examined by comparison of performance on two versions of the 3:2 polyrhythm. In one (simultaneous) version, each cycle of the polyrhythm began with a simultaneous left- and right-hand tap. In the other (shifted) version a 100-ms interval was introduced between the initial left and right taps in each cycle. Examination of the pattern of variances and covariances among intertap intervals suggested that most of the subjects in this study adopted an integrated motor organization that involved interleaving the timing of the two hands. Further analysis revealed that a serial chained model described the pattern of covariances best for the simultaneous pattern, whereas a hierarchical organization described the pattern of covariances for the shifted pattern best. The finding that performance was more accurate with integrated tones than with streamed tones provides some support for a perceptual-motor facilitation hypothesis.     

On the distinction between artifacts and information

Sperling, Landy, Dosher, and Perkins (1989) argued that all previous research on the kinetic depth effect has been contaminated by stimulus artifacts, and they developed a new task that they believe can successfully overcome this problem. The present discussion offers a counter-argument that artifacts are not as pervasive in previous research as Sperling et al. imply and that their proposed method is subject to precisely the same limitations as earlier studies. Also discussed are some general guidelines of experimental design in this type of research to minimize the possibility that subjects will adopt an inappropriate response strategy that does not truly reflect their visual perceptions of three-dimensional form.     

Visual perception of smoothly curved surfaces from double-projected contour patterns

This research was designed to examine how human observers are able to perceive the 3-dimensional structure of smoothly curved surfaces from projected patterns of surface contours. Displays were generated by using a method of double projection that made it possible to cover a surface with a wide range of contour patterns of varying geometric structure and to eliminate systematic variations of image shading. The compelling impression of 3-dimensional form from these patterns provides strong evidence that the ability of observers to perceptually interpret surface contours is considerably less restrictive than would be reasonable to expect on the basis of existing computational models. Results suggest that the perceptual analysis of surface contours is able to exploit statistical regularities of contour structure over appropriately large regions of visual space.     

Understanding the Determinants of Consumer Composting Behavior1

This study compared 3 models of waste management behavior: (a) a theory of reasoned action model, (b) an environmental belief-behavior model, and (c) an integrated waste management model which is based on the theory of planned behavior. The three models were compared using data from a sample of over 1,400 individual respondents who each completed a survey and a 2-week diary of their consumer composting activities. Overall, the results suggest that while the environmental beliefs-behavior model and the integrated waste management models both fit the data well, the integrated waste management model provided better predictive power and offers significant insight into the factors that influence composting behavior.     

Unification,Reduction, and Non-Ideal Explanations

Kitcher's unification theory of explanation seems to suggest that only the most reductive accounts can legitimately be termed explanatory. This is not what we find in actual scientific practice. In this paper, I attempt to reconcile these ideas. I claim that Kitcher's theory picks out ideal explanations, but that our term explanation is used to cover other accounts that have a certain relationship with the ideal accounts. At times, versions and portions of ideal explanations can also be considered explanatory.