n-back任务下视觉工作记忆负荷研究

实验采用n-back范式,考察了视觉工作记忆负荷与反应时、辨别力和主观评价的关系,以及空间位置记忆负荷与图形记忆负荷的差异。结果发现,随着记忆负荷的增大,反应时延长,辨别力降低,主观负荷提高。视觉图形记忆任务的负荷水平高于视觉空间位置记忆任务的负荷水平;同时也为视觉图形记忆和视觉空间记忆具有不同的加工过程提供了证据。     

Crewmember performance before, during, and after spaceflight

The development of technologies for monitoring the welfare of crewmembers is a critical requirement for extended spaceflight. Behavior analytic methodologies provide a framework for studying the performance of individuals and groups, and brief computerized tests have been used successfully to examine the impairing effects of sleep, drug, and nutrition manipulations on human behavior. The purpose of the present study was to evaluate the feasibility and sensitivity of repeated performance testing during spaceflight. Four National Aeronautics and Space Administration crewmembers were trained to complete computerized questionnaires and performance tasks at repeated regular intervals before and after a 10-day shuttle mission and at times that interfered minimally with other mission activities during spaceflight. Two types of performance, Digit-Symbol Substitution trial completion rates and response times during the most complex Number Recognition trials, were altered slightly during spaceflight. All other dimensions of the performance tasks remained essentially unchanged over the course of the study. Verbal ratings of Fatigue increased slightly during spaceflight and decreased during the postflight test sessions. Arousal ratings increased during spaceflight and decreased postflight. No other consistent changes in rating-scale measures were observed over the course of the study. Crewmembers completed all mission requirements in an efficient manner with no indication of clinically significant behavioral impairment during the 10-day spaceflight. These results support the feasibility and utility of computerized task performances and questionnaire rating scales for repeated measurement of behavior during spaceflight.     

Effects of adaptive cruise control and highly automated driving on workload and situation awareness: A review of the empirical evidence

Adaptive cruise control (ACC), a driver assistance system that controls longitudinal motion, has been introduced in consumer cars in 1995. A next milestone is highly automated driving (HAD), a system that automates both longitudinal and lateral motion. We investigated the effects of ACC and HAD on drivers’ workload and situation awareness through a meta-analysis and narrative review of simulator and on-road studies. Based on a total of 32 studies, the unweighted mean self-reported workload was 43.5% for manual driving, 38.6% for ACC driving, and 22.7% for HAD (0% = minimum, 100 = maximum on the NASA Task Load Index or Rating Scale Mental Effort). Based on 12 studies, the number of tasks completed on an in-vehicle display relative to manual driving (100%) was 112% for ACC and 261% for HAD. Drivers of a highly automated car, and to a lesser extent ACC drivers, are likely to pick up tasks that are unrelated to driving. Both ACC and HAD can result in improved situation awareness compared to manual driving if drivers are motivated or instructed to detect objects in the environment. However, if drivers are engaged in non-driving tasks, situation awareness deteriorates for ACC and HAD compared to manual driving. The results of this review are consistent with the hypothesis that, from a Human Factors perspective, HAD is markedly different from ACC driving, because the driver of a highly automated car has the possibility, for better or worse, to divert attention to secondary tasks, whereas an ACC driver still has to attend to the roadway.     

Representation and misrepresentation: Tufte and the Morton Thiokol engineers on the Challenger

This paper examines the role of the Morton Thiokol engineers in the decisions surrounding the launch of the Challenger, particularly with reference to an analysis of this event by Edward Tufte. The engineers at Morton Thiokol recommended against the launch of Challenger because the projected launch temperature between 26°F to 29°F was far outside their field database of successful launches. The engineers had asked for, but not received, data necessary to determine the cause of massive blow-by on the launch the previous January, and they had informed their managers and NASA that continuing flights could be catastrophic if the cause of the problems with the launches was not discovered. The authors conclude that the engineers thus did what they were ethically as well as professionally obligated to do. This paper came about as a result of an experimental class called ‘The Challenger’ at the Rochester Institute of Technology (RIT) which drew faculty from four different disciplines, teaching about various aspects of the Challenger disaster. Wade Robison was one of those professors, and David Hoeker and Stefan Young were members of the class in their freshman year as engineering students. We all owe thanks to the other professors in the class—Dominique LePoutre (Language and Interpreting Education, National Technical Institute for the Deaf), Erhan Mergen (College of Business), and Rose Marie Toscano (Liberal Arts Support, National Technical Institute for the Deaf). We also need to thank Stan McKenzie, Provost at RIT, and Kit Mayberry, Associate Provost, for their conceiving of the program that supported the class and for their financial and moral support. The paper has been presented at three conferences and circulated widely. We want to thank those who forced us to rework the paper because of their cogent queries, especially Michael Pritchard, David Suits, Steve Warshaw, and an anonymous reviewer.