Obviously then this book will be more relevant to those interested in computer architecture and the development of addressing schemes for large data bases than to those who want to understand human memory. This book might have some interesting ideas for those interested in theoretical work on human memory, but these ideas are no more than possibilities. To go from possibilities to plausibilities one has to test models and theories against data, and that remains to be done. Bennet Murdock University of Toronto Toronto, Ontario M5S IA1 Canada G. Ljunggren and S. Dornic (eds.), Psychophysics Berlin, 1989.
in Action.
Springer-Verlag,
The blurb describes this book as ‘giving a topical overview of current research’ in ‘different areas of modern psychophysics’. But that is not what the book is intended to be. It is by way of being a festschrift for Gunnar Borg on his sixtieth birthday, and its contents reflect his interests and his associates. The contents prove to be a collection of papers that vary widely in their level and their interest. They range from theoretical discussions to detailed research reports. Borg’s pre-eminent contribution has been the development of his RPE scale for rating perceived exertion, which has gone through more than one version. In using this, the subject is asked to rate his experienced effort by making a numerical response, e.g. in the range 0 to 10, guided by numerical definitions of a number of anchors, such as ‘Extremely weak’, ‘Very weak’, and so on. There are three points of interest about this scale. The first is Borg’s claim that it allows the experiences of different subjects to be matched. It might seem that we cannot say whether the experienced effort that one subject chooses to describe as ‘Moderate’ is the same as the experience that another subject may assign that label to. Borg bypasses this difficulty by assuming that the strongest possible experience of effort is the same for all people: with that level as an anchor other labels can be equated. An equivalent way of expressing this claim is that the range of experience from nothing at all to the maximum possible is the same for all subjects. The second point of interest is the finding that subjects and patients, perhaps after training, may use the scale so that a given label, such as ‘Strong’, corresponds to similar heart-rates across subjects. Third is the practical point that the scale has become popular in clinical work especially in Scandinavia as a means of establishing a common
Book reoiews
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language between physicians and patients that allows degrees of exertion to be specified. This is background, and it is to be regretted that the book does not start with a contribution, preferably by Borg himself, that would summarise the history of the scale and his main positions. What it does start with is a short article by Saga1 which tells us baldly that Borg’s postulate (the equal range postulate above) allows us to obtain scientific knowledge of other minds. However, it does not examine obvious difficulties such as the question whether a claim that purports to be empirical but cannot in any way be tested can be scientifically useful. Seven theoretical and experimental papers follow. Eisler discusses some experimental cases in which different mathematical models make the same predictions. Hellstrom reviews his work on the time order error and extends its application. Hunt and Sams offer a somewhat turgid account of what they call Human Self-Assessment Process Theory. Marks makes the somewhat strange claim that ‘a single general law or rule can govern dozens or even millions of specific cases, providing a looking glass through [sic] which scientists can observe and interpret a Blakean world in a gram of sand’ - laws are not observation or measuring instruments nor can one look through a looking glass - and then presents some interesting data on cross-modal correspondences. Scharf, Possamai’ and Bonnel provide a useful short review of the use of probe signals in studying attention. J.C. Stevens examines how perceived effort increases with time for static and dynamic exertion, and R. Teghtsoonian argues for the importance of examining psychophysical scales for individual observers. The book concludes with four physiological and clinical papers in which the RPE scale is employed. Of special interest is the observation by Robertson and Metz that blood pH rather than lactic acid level determines rated perceptions of exertion. One is left with the general impression one might get from reading through a volume of a journal in the field, but one in which papers have not been refereed and authors have taken varying advantage of this freedom.
Department
M. Treisman of Experimental Psychology University of Oxford South Parks Road Oxford, OX1 3UD UK
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