240 BOOK REVIEWS

AJazia, by A. Kreindler and A. Fradis, 319 pages, 18 illustrations, 57 tables, Editura Academiei Repu- blicii Socialiste Romfinia, Bucharest, 1970, Lei 22.50.

The purpose of this book is to give a review of classical and modern points of view concerning the pathology of language.

After a brief exposition of the historical evolution of the concept of aphasia, its pathological basis is analysed. The authors reject hypotheses empha- sizing the differences between types of aphasia re- suiting from various focal lesions and from attempts to delimit the "language centres", Considering aphasic disorders as an expression of general disturbances in the interneuronal relationship, they propose a terminological innovation, relating to the effects of so-called "repercussion of neuronal lesion'" on a neuronal circuit.

The physiopathology of aphasia is debated in all respects including the role of apraxia, alexia, internal language, auditory input and cortical dynamics in the genesis of aphasic disorders. Special attention is given to the relationships between

hemispheral dominance and aphasia, In the sections on "Clinical investigations in

aphasia" and "Clinical forms" some original testing methods are presented. The learning disabilities in children and in polyglots are particularly well dts- cussed.

The chapter assigned to neuropsychotogy pro- vides a comprehensive analysis of memory, atten- tion, thinking and temporo-spatial orientation in aphasic patients.

It was hoped that the monograph would stimulate increased cross-communication among diverse scientific disciplines. Thus an attempt to apply methods of information theory 113 the study of aphasic language has given useful information. These studies have allowed expres~on in a quanti- tative form of disturbances at the phonetic level, in paucity of vocabulary' and morphological and syntactical disorders which are specific for aphasia.

The monograph covering modern progress in this field - is indeed an exhaustive source of infor- mation presented in a remarkably clear style.

I 1. Rt~D~

Excitatory Synaptic Mechanisms (Proceedings of the fifth International Meeting of Neurobiologists, Sandet]ord, Norway, 5-17 September 1969), by P. Andersen and J. K. S. Jansen (Eds.), 354 pages, 179 illustrations, 6 tables, Universitetsforlaget, Oslo, Boston, Ma., lt}70, Nkr. 168.---, US $28.00.

Nearly 70 contributors made up the Proceedings of the 5th International Meeting of Neurobiologists which was held in Norway in September, 1969,

The reviewer's task of conveying to possible purchasers his estimate of the worth of such a book could be made easier. By using the convention of the gramophone record critic, he could withou!

hesitation award three stars for performance and three stars for reproduction to this volume of High-. lights of Synaptic Physiology. One may be forgiven some envy of those privileged to attend -the meeting but the book does much to compensate.

Per Andersen and Jan Jansen have edited the contributions of their distinguished workers very well. The discussions are not fragmentary because they too have been specially written and edited rather than transposed from magnetic tape. The result is a highly critical and informative surxey of the anatomy and physiology of synaptic excitation.

1~,. (}. WILLISON

Electrical Signs oJ Nervous Actit'ity. by J. Erlanger and H. S. Gasser, 2nd edition of the first Eldridge Reeves Johnson Foundation Lectures published in t937 by the University of Pennsylvania Press, xiv + 242 pages, 113 illustrations, 4 tables, Oxford University Press, London, 1970, £3.60.

The reprinting of Electrical Signs ol Nervous Activity is a tribute to the enduring quality of its contents. The Johnson lectures were given in 1936 after Erlanger and Gasser had shared the Nobel prize for their electrophysiological studies. The authors had first collaborated in a study of trau- matic shock and then, in 1922. they published the first account of the application of the cathode ray tube to the study of nerve action potentials. Subsequently they described the relationships be- tween nerve fibre diameter, conduction velocity and excitability, the time course of the refractory period, and the different sensitivities of fibres to anoxia and

local anaesthetics. All of these tundamental obser- vations were included in the lectures: the final chapter by Gasser also contains his fascinating studies with Hughes on cord dorsum potentials. The book contains full bibliographies for each author. It is of interest that both Er!angerand Gasser continued laboratory work until well into their seventies and that two of the last papers by Gasser were of great importance. One of these was con- cerned with the ultrastructure of C fibres: the other showed, perhaps ironically, that some of the previously-described elevations in the nerve com- pound action potential were consequences of the recording technique and not due to the existence of distinct fibre groups. Now that this classic work has become available again, many physiologists will wish to have their own copies and no biological department should be without one

A J. McCoMAs

d. neurol. Sci, 1971, I4:237-242