Control of gaze by brain stem neurons

206 not minimised by the authors of the three chapters on this subject. Nevertheless it is likely that some asymmetry related to the lateralisation of speech function will eventually by confirmed. Turning to speech perception, Chapman and his colleagues and Marsh and Brown are optimistic that their methods will be confirmed as showing differences in EP according to the meaning of the word used as stimulus, clearly a most important finding. More than half the book consists of the description of attempts to demonstrate asymmetry accompanying mental tasks appropriate to the functions of the two hemispheres. The result is simply disagreement. In particular Friedman and his group find no such asymmetry and the inherent difficulties, including underlying asymmetries of the EEG, are emphasised by Donchin. Buchsbaum and Drago conclude their chapter with the statement that: "In experiments where no task is assigned, subjects invent tasks which may influence hemispheric asymmetry in unpredictable ways". Man is indeed a most unsatisfactory experimental animal. The editor is to be congratulated on assembling the discussions summarised in this book which are of great interest and potential importance. It is to be hoped that the attention hitherto paid to the amplitude and form of the variable potentials will not distract attention from other measurements of possible significance, in particular the latency, which in general has proved more valuable in the assessment of subcortical EP. W. B. Matthews

Control of Gaze by Brain Stem Neurons ( D e v e l o p m e n t s in N e u r o s c i e n c e , V o l . 1) ( P r o c e e d i n g s o f a S y m p o s i u m , Paris, 12-15 July, 1977), by R. B a k e r a n d A . B e r t h o z (Eds.), xv + 514 pages, 215 i l l u s t r a t i o n s , 9 tables, E l s e v i e r / N o r t h - H o l l a n d B i o m e d i c a l Press, A m s t e r d a m , N e w Y o r k , 1977, U S $ 59.95, Dfl 147.00. Few areas of neurophysiology can have advanced as rapidly as that concerning the control of eye movement. Neurologists, not to mention workers in the basic sciences, must find the wealth of data on gaze control bewildering. It is therefore valuable to have a volume that summarises the current position succinctly and so clearly separates hypothesis from fact. This book is the result of a symposium held at the Abbaye de Royaumont, in mid 1977, at which leading workers in the field of gaze control reviewed the present position in open forum and enables a much wider audience than could possibly have attended the symposium to benefit from their discussion. The format of the book is a number of sections dealing respectively with descriptions and models of eye movement, the anatomical and physiological organisation of brain stem control of these movements, the importance of vestibular control and the influence of supranuclear factors. Each section is a series of papers by leading workers in the field. Many of these papers take the form of a review rather than dealing with minute areas of the latest work (an irritating feature of many modern symposia). Most of the chapters are an excellent account of the present position concerning virtually all areas of brain stem gaze control and all have an extensive bibliography. The only weakness is the limited coverage of cortical control in the last section--perhaps understandable in a symposium primarily concerned with brain stern events. At the end of each section is a synthesis of the evening workshop in which one scientist summarises the discussion. This is a particularly useful way of presenting the data and avoids the annoying "point scoring" that tends to occur in such workshops which looks trivial in print. This book will be an important text for not only the basic scientist over the next five years, but also for the enquiring neurologist, particularly one interested in neuro-ophthalmology. The editors are to be congratulated in the speedy production of a stimulating and valuable text. Peter Rudge

The Ocular and Cerebrospinal Fluids ( F o g a r t y I n t e r n a t i o n a l C e n t e r S y m p o s i u m , 3 - 6 M a y , 1976, B e t h e s d a , M D ) ( R e p r i n t e d f r o m t h e S u p p l e m e n t t o E x p e r i m e n t a l Eye R e s e a r c h , Vol. 25, 1977), by L. Z. Bito, H . D a v s o n a n d J. D . F e n s t e r m a c h e r (Eds.), xvi +

561 pages, 292 i l l u s t r a t i o n s , 57 tables, A c a d e m i c Press, L o n d o n , N e w Y o r k ,

San F r a n c i s c o , 1977, £ 20.00, U S $ 39.00.