PERFORMANCE UNDER STRESS Human Factors in Defence Series Editors: Dr Don Harris, Cranfield University, UK Professor Neville Stanton, Brunel University, UK Professor Eduardo Salas, University of Central Florida, USA Human factors is key to enabling today’s armed forces to implement their vision to ‘produce battle-winning people and equipment that are fit for the challenge of today, ready for the tasks of tomorrow and capable of building for the future’ (source: UK MoD). Modern armed forces fulfil a wider variety of roles than ever before. In addition to defending sovereign territory and prosecuting armed conflicts, military personnel are engaged in homeland defence and in undertaking peacekeeping operations and delivering humanitarian aid right across the world. This requires top class personnel, trained to the highest standards in the use of first class equipment. The military has long recognised that good human factors is essential if these aims are to be achieved. The defence sector is far and away the largest employer of human factors personnel across the globe and is the largest funder of basic and applied research. Much of this research is applicable to a wide audience, not just the military; this series aims to give readers access to some of this high quality work. Ashgate’s Human Factors in Defence series comprises of specially commissioned books from internationally recognised experts in the field. They provide in-depth, authoritative accounts of key human factors issues being addressed by the defence industry across the world. Performance Under Stress Edited by PETER A. HANCOCK and JAMES L. SZALMA University of Central Florida, USA © Peter A. Hancock and James L. Szalma 2008 All rights reserved. No part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means, electronic, mechanical, photocopying, recording or otherwise without the prior permission of the publisher. Peter A. Hancock and James L. Szalma have asserted their moral right under the Copyright, Designs and Patents Act, 1988, to be identified as the editors of this work. Published by Ashgate Publishing Limited Ashgate Publishing Company Gower House Suite 420 Croft Road 101 Cherry Street Aldershot Burlington, VT 05401-4405 Hampshire GU11 3HR USA England Ashgate website: http://www.ashgate.com British Library Cataloguing in Publication Data Performance under stress. - (Human factors in defence) 1. Psychology, Military 2. Stress (Psychology) 3. Performance I. Hancock, Peter A., 1953- II. Szalma, James L. 355'.0019 Library of Congress Cataloging-in-Publication Data Performance under stress / edited by Peter A. Hancock and James L. Szalma. p. cm. -- (Human factors in defence) Includes bibliographical references and index. ISBN 978-0-7546-7059-9 1. Psychology, Military. 2. Soldiers--Job stress. 3. Combat--Psychological aspects. 4. Stress (Physiology) 5. Stress (Psychology) 6. Performance. 7. Psychophysiology. I. Hancock, Peter A., 1953- II. Szalma, James L. U22.3.P465 2007 355.1'23--dc22 2007026005 ISBN 978-0-7546-7059-9 Printed and bound in Great Britain by MPG Books Ltd, Bodmin, Cornwall. Contents List of Figures vii List of Tables xi Preface xiii Foreword xv 1 Stress and Performance P.A. Hancock and J.L. Szalma 1 2 Contemporary and Future Battlefields: Soldier Stresses and Performance Gerald P. Krueger 19 3 Mitigating the Adverse Effects of Workload, Stress, and Fatigue with Adaptive Automation Raja Parasuraman and P.A. Hancock 45 4 Concentration, Stress and Performance Anthony W.K. Gaillard 59 5 Remote Command and Control, Trust, Stress, and Soldier Performance Kip Smith 77 6 Changes in Soldier’s Information Processing Capability under Stress Wayne C. Harris, Karol G. Ross and P.A. Hancock 101 7 Vigilance, Workload, and Stress Joel. S. Warm, Gerald Matthews and Victor S. Finomore Jr. 115 8 Temporal Regulation and Temporal Cognition: Biological and Psychological Aspects of Time Stress Rene J. de Pontbriand, Laurel E. Allender and Francis J. Doyle, III 143 9 Positive Psychology: Adaptation, Leadership, and Performance in Exceptional Circumstances Michael D. Matthews 163 10 Stress and Teams: How Stress Affects Decision Making at the Team Level C. Shawn Burke, Heather A. Priest, Eduardo Salas, Dana Sims and Katie Mayer 181 11 Mitigating the Effects of Stress through Cognitive Readiness Linda T. Fatkin and Debbie Patton 209 vi Performance Under Stress 12 Fatigue and its Effect on Performance in Military Environments N.L. Miller, P. Matsangas and L.G. Shattuck 231 13 Multi-Modal Information Display under Stress T. Oron-Gilad and P.A. Hancock 251 14 Stress Exposure Training: An Event-Based Approach James E. Driskell, Eduardo Salas, Joan H. Johnston and Terry N. Wollert 271 15 Augmenting Multi-Cultural Collaboration Mary T. Dzindolet, Linda G. Pierce and Melissa W. Dixon 287 16 Individual Differences in Stress Reaction James L. Szalma 323 17 Stress and Performance: Experiences from Iraq LTC J.L. Merlo, CPT Michael A. Szalma, and P.A. Hancock 359 Index 379 List of Figures 4.1 The concentration model, illustrating the influence of the factors that affect cognitive processing 61 4.2 The relation between energy mobilization and directed attention 68 4.3 The level of concentration is determined by the balance between factors that motivate and generate positive energy, and factors such as distraction fatigue, and stress that inhibit or distort energy mobilization and attention 73 5.1 Layout of the paintball assault lane 95 5.2 Mean and standard errors of response times to the order to move for the two sequences of data acquisition, Experiment 1 96 5.3 Mean and standard errors of response times to the order to fire for the two sequences of data acquisition, Experiment 1 96 5.4 Mean and standard errors of response times to the order to move for the two sequences of data acquisition, Experiment 2 97 5.5 Mean and standard errors of response times to the order to fire for the two sequences of data acquisition, Experiment 2 97 5.6 Mean and standard errors of response times to the order to move collapsed across trial sequence, Experiment 3 98 5.7 Mean and standard errors of response times to the order to fire collapsed across trial sequence, Experiment 3 98 5.8 Mean and standard errors of the soldiers’ self-report data on the relative level of trust experienced in the leader-present (collocated), remote, and buzzer conditions showing higher levels of trust in the leader-present condition 99 5.9 Mean and standard errors of response times to the order to move collapsed across trial sequence, Experiment 4 99 5.10 Mean and standard errors of response times to the order to fire collapsed across trial sequence, Experiment 4 100 5.11 Scatter plot and best-fit linear regression function showing the significant negative association between the difference in experienced trust and the difference in move time between the remote- and present-leader conditions 100 7.1 The downs and ups of vigilance. The vigilance decrement as a decline in signal detection over time or an increase in response time to correct detections over time 116 7.2 The rate of gain of workload over time 118 7.3 NASA-TLX workload profile for vigilance tasks 119 7.4a Mean overall workload scores on the NASA-TLX for Control, KR, and Cue groups 121 7.4b Mean boredom scores on the TBS for Control, KR, and Cue groups 121 7.5 The relation between the vigilance decrement and cerebral blood flow velocity 124 7.6 Patterns of stress state change in four studies of vigilance 128 8.1 Three levels of temporal factors 144 viii Performance Under Stress 10.1 Team decision making under stress framework 198 11.1 Timeline for Stress and Readiness Assessment (SARA) methodology for administering RAMS component 212 11.2 Mean (+SEM) MAACL-R Anxiety scores for referent groups collected after specific, challenging events 215 11.3 Mean (+SEM) MAACL-R Depression scores for referent groups collected after specific, challenging events 215 11.4 Mean (+SEM) MAACL-R Hostility scores for referent groups collected after specific, challenging events 216 11.5 Mean (+SEM) MAACL-R Positive Affect scores for referent groups collected after specific, challenging events 216 12.1 Sleep patterns over the lifespan 233 12.2 Sleep stages over a typical eight-hour sleep period 234 12.3 Categories of insufficient sleep 235 12.4 Relationship between stressors, mediating factors and performance 237 12.1 (photo) Soldier sleeping in combat conditions 239 12.5 Fatigue countermeasures 240 12.6 Fatigue Avoidance Scheduling Tool (FAST) 241 13.1 Example of the pictorial, written and verbal WCCOM (top) and the color stimulus (bottom) that elicited the key press response 253 13.2 Presentation by response format interaction for the WCCOM task 255 13.3 Presentation by task demand interaction for the WCCOM 256 13.4 The SAST II facility including the weapon and the visual display 257 13.5 Screenshot from the SAST II displaying the two types of stimuli/targets superimposed on the silhouette stimuli 258 13.6 Interaction between the presence of a target and working memory demand on the secondary task 259 13.7 The effects of working memory demands (secondary task) on shooting accuracy 260 13.8 Mean β by AC group and modality 262 13.9 Mean overall workload rating in each task for low and high AC groups 263 13.10 Box representation of compliance results in Study i) 267 15.1 McGrath’s circumplex of group tasks 288 16.1 The cognitive-adaptive framework, illustrating the “adaptive triangle” of skill, knowledge, and action and the multiple levels of analysis 327 16.2 The Maximal Adaptability Model 329 16.3 The Maximal Adaptability Model with Task Dimensions Included 330 16.4 Response bias (c) as a function of extraversion and white noise exposure.