"Color Vision - from genes to perception" edited by Karl R. Gegenfurtner and Lindsay T. Sharpe. Cambridge university Press, Cambridge, 1999.
Upon receiving this book from the Nathan Library (Victorian College of Optometry), I got a bit nervous about the ambitious title: "... from Genes to Perception"! Indeed, this promises coverage of a vast scientific landscape conventionally considered more or less as separate islands of speciality. Even highly motivated readers not coerced to review would surely balk at a treatise spanning fields as diverse as molecular genetics and recombinant gene technology, in vivo high resolution retinal imaging, neuro-anatomy, histology and serial electron micrograph reconstruction, intensive computer modelling, retinal and cortical physiology (intracellular and extracellular), and psychology. In this volume however, Gegenfurtner and Sharpe have managed to direct 35 leaders in each of these fields to construct 20 comprehensive yet comprehensible review chapters and have used the common theme of color vision to draw these islands together. Reading this book, an archipelago now can be envisioned: on clear days, views may be gleaned from one island to the next.
The stated aim of this book is to "take a snapshot of our understanding about the visual neuroscience of color vision". This interesting story is told in 4 sections: Part 1 concentrates on photoreceptors and includes a well-presented discussion of the genes involved in coding the protein opsins fundamental to color vision - what happens normally and how things can go awry for color-deficient observers. Details of how light is transduced by the cones to provide the initial biophysical signal for vision is next discussed, followed by presentation of new evidence about how (using adaptive optics) and why (from an evolutionary viewpoint) different cones are distributed in the manner observed within the retinal matrix. Part 2 focuses on retinal circuitry and how the synaptic connections are made between each type of neurone (that we know about!) from the photoreceptors to the ganglion cells. The discussion always highlights the functional point of view: how the essential purpose of color-vision is served by the observed retinal wiring. In a tacit admission that we lack appreciation of the significance, if any, of the thalamus for color (or any other visual aspect), Part 3 jumps straight to cortical processing. Here results from psychophysical, electrophysiological and neuroimaging experiments are considered, allowing a glimpse of how the higher-order neurones of the brain might concertedly act to process information about the chromatic properties of the seen world. Finally, Part 4 considers our perception of color, including current thoughts on how and why things appear they way they do; the subtleties of chromatic illusions and how these may be manifestations of a visual system changing its operating characteristics in order to work most efficiently.
It is often disappointing that books about color vision fail to incorporate color pictures which do the topic justice - this is an exception. The glossy hard cover suggests an attention to detail in production that is immediately borne out upon opening - the quality of the text layout is superb as are the many reproductions of photographs and diagrams.
I really like this book - its scope is broad but happily in an easy-to-read form that is accessible to the interested and moderately informed lay reader. It makes a welcome contribution to the literature that has been calling for a review since the dating of such "classics" as Robert Boynton's "Human color vision". This book is undoubtedly the next classic in the color vision field, and is a real asset to any library.
Andrew Metha
13 June 2000.
