Effect of workload history on vigilance performance.

Effects of sudden transitions in workload level on performance indices were investigated within the newly emerging paradigm of workload history. It has been previously reported that a sudden decrease in workload level results in a significant immediate decrement in performance (Cumming & Croft, 1973; Goldberg & Stewart, 1980; Matthews, 1986). Study 1 consisted of 198 participants who completed a protocol of training, baseline and test trials designed to examine the effects of workload history on performance. Specifically, this study tested for the reported general decrement in performance and investigated the nature of the decrement. Results indicated that a sudden decrease in workload level results in an immediate significant decrement in response time, total errors, etc., while a sudden increase fails to result in the same immediate decrement. This study reports new findings, i.e., either a sudden increase or decrease could lead to a loss in accuracy and a slowing of response time in a longer time course. An explanation of the decrement is offered in terms of a resource adaptation-depletion model. Study 2 tested whether time on task or fatigue might have been responsible for the decrement in performance following sudden transitions in workload (reported in Study 1). No significant results were found; therefore, it appears that the decrement in performance following workload transitions is a result of something inherent in the workload shift rather than an effect of time on task or fatigue

Effect of Workload History on Task Performance

Objective: This study investigated the effects of workload history (specifically, sudden shifts in workload) on performance. Background: In 1993 the National Research Council identified workload transition as an important concern for human factors researchers. The study of workload history suggests that what an individual has been doing prior to a point in time has an effect on subsequent performance. One trend emerging from workload history studies is that a general decrement in performance is most likely to occur following a decrease in task demand. Method: The 198 participants were randomly assigned to a high-to-low or low-to-high condition. Participants performed a version of the Bakan Vigilance Task while correct responses, response times, and total errors were recorded. Results: Results supported previous research suggesting a workload decrease results in a performance decrement. More importantly, this study reports that either a sudden increase or decrease could lead to a loss in accuracy and a slowing of response time in a longer time course. Conclusion: An explanation of the decrement is offered in terms of adaptation models. In addition, a follow-up study suggested that the decrement is a result of something inherent in the workload shift rather than an effect of fatigue. Application: Workload history (more specifically, a workload shift) has significant implications for many work environments. These implications are particularly salient in occupations where individuals are confronted with varying levels of workload demand, especially safety-sensitive occupations.Yeshttps://us.sagepub.com/en-us/nam/manuscript-submission-guideline

Contentious histories and the perception of threat:China, the United States, and the Korean War- an experimental analysis

Chinese and Korean protests over "revisionist" Japanese histories of World War II are well known. The impact of contested Chinese and US histories of the Korean War on US-China relations today has received less attention. More broadly, there has been little research seeking to systematically explore just how history textbook controversies matter for international relations. This article experimentally manipulates the impact of nation (US/China), of source (in-group/out-group textbooks), and of valence (positive/negative historical narratives) on measures of beliefs about the past, emotions, collective self-esteem, and threat perception in present-day US-China relations. A 2 x 2 x 2 design exposed randomized groups of Chinese and US university students to fictional high school history textbook accounts of the Korean War. Findings reveal significant effects of nation, source, and valence and suggest that the "historical relevance" of a shared past to national identities in the present has a dramatic impact on how historical controversies affect threat perception.Social Sciences, InterdisciplinarySSCI2ARTICLE3433-465