Table Of ContentElements of Human Performance:
Reaction Processes and Attention
in Human Skill
Elements of Human Performance:
Reaction Processes and Attention
in Human Skill
Andries F. Sanders
Free University, Amsterdam, The Netherlands
~ LAWRENCE ERLBAUM ASSOCIATES, PUBLISHERS
1998 Mahwah, New Jersey London
Copyright C> 1998 by Lawrence Erlbaum Associates, Inc.
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Library of Congress Cataloging-in-Publication-Data
Sanders, A. F. (Andries Frans), 1933-
Elements of human performance : reaction processes and
attention in human skill I Andries Sanders.
p. em.
Includes bibliographical references and index.
ISBN 0-8058-2051-5 (cloth : alk. paper). -ISBN
0-8058-2052-3 (pbk. : alk. paper)
1. Reaction time. 2. Attention. I. Title.
BF317.S34 1997
152.8'3-dc21
97-19997
CIP
Books published by Lawrence Erlbaum Associates are
printed on acid-free paper, and their bindings are chosen
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To H enny, With Love
Contents
Preface ix
Introduction 1
1 Introduction to Reaction Processes 20
2 Reaction Processes: General Properties and Models 30
3 Reaction Processes: Stage Analysis 59
4 Reaction Processes: Effects of Variables 110
5 Reaction Processes: Beyond Traditional Choice-Reaction Time 181
6 Introduction to Attention 215
7 Focused Attention and Search 225
8 Automaticity and Divided Attention 307
vii
viii CONTENTS
9 Energetics, Stress, and Sustained Attention 394
10 The Total Task: Reversal of the Perspective 452
References 507
Author Index 557
Subject Index 569
Preface
This book focuses on two core topics of human performance theory, namely
reaction processes and attention. These were chosen for three main reasons.
First, both fields are neglected in texts on cognitive psychology. Reaction
processes are not discussed at all, perhaps because reaction time tends to be
viewed as a dependent variable rather than as an area of research. As is argued,
it has unique properties that deserve consideration in their own right. Attention
is usually not fully ignored but gets a few pages in a chapter on perception,
presumably because attention has been most often identified with perceptual
selection. This does not reflect present-day views in which attention is related
equally to central processing and to action. The main function of attention
appears to be control and coordination of processes at these various levels of
processing. At the same time, the information flow from perceptual to central
processes and from central to motor processes is the main ingredient of a
reaction process; therefore, the fields are fully intertwined.
The second reason was a wish to describe the present state of the art in the
principal areas of the original "Attention and Performance" symposia (Sanders,
1967a). Some main topics in 1967 were reaction time, dual-task performance,
selective attention, visual search, and vigilance, all of which are therefore
prominent themes in this book. Some have flourished and shown a lot of
progress during recent decades; others suffered from a loss of interest during
the 1970s and 1980s but tended to come back in recent years. I was an active
researcher throughout these years, so the review is biased in favor of my own
research and the research of those with whom I had frequent contacts. In other
words, there is a bias in favor of Dutch contributions, which may actually be of
interest to those who are mainly exposed to American literature.
The third reason was probably the main one and evolved from a growing
concern about the increasing discrepancy between basic and applied research.
Almost all basic research derives from what may be labeled small and simple
laboratory paradigms (Sanders, 1984), artificially created laboratory tasks car-
ix
X PREFACE
ried out by human participants with the aim of uncovering and describing
elementary mental processes. Their advantage is that they allow a systematic
variation of parameters that is indispensable for a more detailed analysis.
However, performance theory has also traditionally been interested in complex
everyday skills, such as typing, driving, flying, monitoring radar or sonar, and
controlling industrial processes. The extent to which evidence from small
paradigms may be generalized and applied to real-life tasks, and from there to
human-factors research, is quite urgent. A few decades ago, this was not felt to
be a problem: The contacts between applied and basic research flourished, and
one may rightly say that at that time, the basic questions about reaction
processes and attention evolved from applied problems.
Since then, increasing doubts have been expressed about the value of
laboratory research to real life (e.g., Flach, 1990). There is the spreading
conviction among applied investigators that basic research is irrelevant to their
purposes. On the other hand, basic researchers have tended to treat applied
problems with some disdain, perhaps stimulated by the anti-industrial political
tide during the 1970s. Researchers who have tried to keep up in both basic and
applied research experience radically different worlds. One consists of detailed
experiments aimed at testing equally detailed hypotheses about human per
formance; the other consists of solving human-factor problems in evermore
complex systems. The applied problems are usually much more composite than
the basic ones that are based on more elementary laboratory tasks. I worked for
many years in a setting that encouraged a combination of basic and applied
research. It used to be traditional policy of most applied laboratories to have a
mixture of applied and related basic research whereas from the 1970s and 1980s
onward, a clear distinction has developed between a basic and an applied type
of investigator. Thus, I found it shocking to hear basic research characterized
as "journal research" somewhere during the mid-1970s. The research programs
of most applied laboratories have now drastically changed. They largely exclude
basic research, and some openly aim at a less academic attitude. What has
happened? Is it merely the shortsightedness of desiring short-term applied
success at the cost of in-depth investment in basic research, or does it reflect
something more serious?
Basic and applied research have different perspectives that may be labeled
process orientation versus task orientation (Schmidt, 1987). An applied prob
lem asks for a solution without bothering too much about theoretical under
pinning . In contrast, basic research asks for experiments relevant to designing
and testing models on the underlying processes. An applied problem arises from
reality; a basic one from theory. Applied issues ask for widely applicable
theoretical concepts, whereas basic problems are concerned with the micro
structure of a process. It is evident that these differences may easily lead to a
schism. Do basic and applied research really need each other? In the natural
sciences, there are various examples of technological discoveries that had little
or no underlying basic theory, yet there are as many examples in which basic
PREFACE xi
science identified key constraints, unlocked progress with modest effort, or
provided new ways for conceptualization. In fact, basic and applied approaches
need each other because they become empty when practiced in isolation.
Moreover, both have their own position, value, and potential that should not
be blurred by designing studies in the middle as a compromise between basic
and applied research. Such attempts usually fail to serve either a basic or an
applied goal. It is a prerequisite for basic research to abstract from reality, which
means that experimental conditions do not aim at simulating a real-life situ
ation. In contrast, applied research needs a simulation of reality, but usually has
little theoretical rationale. Valid as this all may be as a metastatement, there
remains the issue of the ecological validity of the small behavioral paradigm.
The concern is that the small paradigm represents nothing but an artifactual
situation that has little or nothing to say about the richness of reality. If this
were the case, the schism between basic and applied research would obviously
be quite serious.
Most chapters are devoted to basic research and theoretical issues on reaction
processes and attention. Whenever it makes sense, the applied spin-off is
discussed on completion of a theoretical argument. In the last chapter, the
emphasis is task oriented and deals with real-life skills and major applied
techniques in system design. Indeed, this is a radically different world. To what
extent do the applied techniques rely on or need basic research results? Is it
possible to bridge the gap? These questions are discussed within the context of
issues on reaction processes and attention.
ACKNOWLEDGMENTS
The original plan of reviewing these themes became more concrete when I had
the opportunity of spending a sabbatical at the Netherlands Institute for
Advanced Studies (NIAS) at Wassenaar during the academic year 1994 to 1995.
I am grateful for the highly stimulating atmosphere at NIAS, with the result
that I left Wassenaar in the summer of 1995 with a first draft. Then, individual
chapters were sent to various reviewers for critical comments. I wish to thank
them for their highly relevant comments that led to considerable revisions of
most chapters. The reviewers remarks came from the Cognitive Psychology
Unit of the Department of Psychology of the Free University, namely Sander
Los, Mieke Donk, Paul Kess, Dirk Knol, and Floor van der Ham; from the
Psychology Department of the University of Amsterdam, namely,Jo Sergeant,
Maurits van der Molen, and Harold Pashler (on leave from UCSD); and from
the TNO Institute for Human Factors, namely Herke Schuffel, Wim Verwey,
Jan Theeuwes, and Hans Korteling. I am particularly grateful to Eric van
Rossum, who did a splendid job with respect to the artwork. During the final
phase I also had much support from the secretarial staff-Alies, Heleen, and
