Dissociating the components of switch cost using two-to-two cue-task mapping

In the task switch paradigm, a switch of task is typically accompanied by a change in task cue. It has been proposed that the performance deficit usually observed when switching tasks is actually the result of changing cues. To test this possibility, we used a 2:2 cue-task mapping in which each cue indicated 2 different tasks. With advance presentation of a cue, the cost associated with changing cues disappeared, though a substantial task switch cost remained. Without advance cues, the relative contributions of task switch cost and cue change cost differed by transition frequencies. The results suggest that task execution contributes to switch cost independent of cue changes.     

Optimal sequences of trials for balancing practice and repetition effects

This paper describes procedures for generating trial sequences to balance out practice effects and intertrial repetition effects in experiments consisting of repeated trials. In the sequences presented, each stimulus appears an equal number of times, is preceded equally often by itself and by each other stimulus, and is distributed in a “balanced” manner throughout the block of trials. Two criteria for balance are employed. One criterion aims to equalize the average position of each stimulus in the sequence. The second criterion maintains, as much as possible, a uniform interval between appearances of each stimulus in the sequence. For each criterion, optimal or near-optimal sequences are presented for experiments involving from three to nine different stimulus conditions. Suggestions are included for extending (e.g., doubling or tripling) the length of the sequences.     

School-Aged Children’s Attachment Dismissal Prospectively Predicts Divergence of Their Behavioral and Self-Reported Anxiety

Recent studies on attachment in middle childhood suggest that dismissing children tend to underreport their psychological distress relative to physiological indices of distress. However, this has yet to be examined in the context of behavioral indicators of distress. In this longitudinal study, a community sample of children (N?=?34, M _age?=?9.59 years) completed the Child Attachment Interview at Time 1. Three years later, they returned and completed the Trier Social Stress Task for Children (TSST-C), providing ratings of their state anxiety before and after the stressor. Four raters coded children’s behavioral signs of anxiety (e.g., non-signaling gestures, eye movement, posture, facial expression) on a 7-point scale during the storytelling and arithmetic tasks in the TSST-C. Hierarchical linear regressions revealed that greater attachment dismissal was associated with greater behavioral anxiety in both the story and math tasks, but was not associated with greater increases in self-reported anxiety. Dismissal prospectively predicted increased divergence of behavioral and self-reported anxiety, such that higher dismissal was associated with higher divergence scores (i.e., underreporting of anxiety relative to behavioral indicators). We discuss these results in terms of their contribution to understanding attachment and emotion in an understudied developmental phase.     

The effect of highly concentrated oxygen administration on cerebral activation levels and lateralization in visuospatial tasks

This study investigated what effect a 30% oxygen administration had on visuospatial cognitive performance and cerebral activation and lateralization using fMRI. Eight college students were selected as the subjects for this study. An oxygen dispenser that provided 21% and 30% oxygen at a constant rate of 8L/min was developed. In order to measure the performance level of visuospatial cognition, two psychological tests were also developed. The experiment consisted of two runs, one for a visuospatial cognition task with normal air (21% oxygen) and the other for a visuospatial cognition task with hyperoxic air (30% oxygen). Functional brain images were taken with a 3T MRI using the single-shot EPI method. The results of the visuospatial behavioral analysis reveal that accuracy rates were enhanced with 30% oxygen administration when compared to 21% oxygen. There were more activations observed at the bilateral occipital, parietal, and frontal lobes with 30% oxygen administration. However, decreased cerebrum lateralization was observed with 30% oxygen administration in the same regions compared with 21% oxygen administration. Thus, it is concluded that the positive effect on the visuospatial cognitive performance level by the highly concentrated oxygen administration resulted from an increase of cerebrum activation and a decrease of cerebrum lateralization.     

The Role of the Quality of College‐Based Relationship on Social Media in College‐to‐Work Transition of Korean College Students: The Longitudinal Examination of Intimacy on Social Media,Social Capital,and Loneliness

This study investigated the mediation effects of social capital on the associations between the quality of relationship, intimacy in particular, with college friends on social media and loneliness during college‐to‐work transition of Korean college students. Longitudinal data were collected from three surveys with a 6‐month interval. The first wave of the survey was completed by 521 participants; 110 graduates participated in the second wave, and 175 in the third wave. Latent growth modeling analysis revealed that the linear growth function produced a better fit than the no‐growth models for intimacy on social media, social capital, and loneliness. While intimacy on social media and bonding capital increased during the three‐time interval, bridging capital and loneliness decreased. In addition, the slope of intimacy on social media was positively related to the slopes of bridging and bonding capital, both of which, in turn, had a negative association with the slope of loneliness. These findings indicate the beneficial role of the quality of relationship on social media in college‐to‐work transition.     

The Effect of Highly Concentrated Oxygen Administration on Cerebral Activation Levels and Lateralization in Visuospatial Tasks

This study investigated what effect a 30% oxygen administration had on visuospatial cognitive performance and cerebral activation and lateralization using fMRI. Eight college students were selected as the subjects for this study. An oxygen dispenser that provided 21% and 30% oxygen at a constant rate of 8L/min was developed. In order to measure the performance level of visuospatial cognition, two psychological tests were also developed. The experiment consisted of two runs, one for a visuospatial cognition task with normal air (21% oxygen) and the other for a visuospatial cognition task with hyperoxic air (30% oxygen). Functional brain images were taken with a 3T MRI using the single-shot EPI method. The results of the visuospatial behavioral analysis reveal that accuracy rates were enhanced with 30% oxygen administration when compared to 21% oxygen. There were more activations observed at the bilateral occipital, parietal, and frontal lobes with 30% oxygen administration. However, decreased cerebrum lateralization was observed with 30% oxygen administration in the same regions compared with 21% oxygen administration. Thus, it is concluded that the positive effect on the visuospatial cognitive performance level by the highly concentrated oxygen administration resulted from an increase of cerebrum activation and a decrease of cerebrum lateralization.     

Suicides around Major Public Holidays in South Korea

A dip and peak pattern of suicide around major public holidays has been found in developed countries and explained by the broken promise effect. Focusing on two major holidays in South Korea (New Year's Day and Thanksgiving Day, both on the lunar calendar), replication of the dip and peak pattern was done by analyzing individual information on all suicides from 1997 to 2014. The replicated pattern revealed the most vulnerable group to be married men aged 50+ in nonmetropolitan areas in 2006–2014. Families, friends, and policy makers can use these findings to save the vulnerable.     

Comprehension‐Based Skill Acquisition

We present a comprehension‐based computational model of UNIX user skill acquisition and performance in a training context (UNICOM). The work extends a comprehension‐based theory of planning to account for skill acquisition and learning. Individual models of 22 UNIX users were constructed and used to simulate user performance on successive command production problems in a training context. Comparisons of model and the human empirical data result in a high degree of agreement, validating the ability of UNICOM to predict user response to training.