European Journal of Personality, Vol. 2, 169-170 (1988)

Book review

Origins of Mental Illness. Temperament, Deviance and Disorder. Gordon Claridge. Blackwell, OxfordMew York. 1985. 213 pp.

In the last two decades, interest in personality psychological explanations of mental illness has declined. Current etiological research done by psychologists is mainly directed towards (1) stress, coping and social support, (2) (social) learning of abnormal behavior and (3) disturbed cognitive processes. Origins of Mental Illness is a book written in the tradition of Pavlov, Eysenck, Gray, Mangan and other researchers interested in an experimental foundation of clinical psychology and investigating temperamental bases of personality and abnormal behavior. In this respect Claridge’s book is a most welcome enrichment of prevailing perspectives on mental illness. The book addresses a wide audience and is written in a clear style comprehensible even to nonprofessionals (for that reason it contains no tables, figures or statistical details).

Five major themes run through the book: (1) Individuals differ fundamentally in the kinds of nervous system they possess. (2) Differences in brain organization become manifest in variations in temperament. (3) Biologically based traits of temperament are synonymous with predispositions to differing forms of mental illness. (4) Some of the most important influences responsible for temperamental variations, and hence predispositions to deviance or mental illness, are genetic in origin. (5) There is a continuum ranging from normality over mild deviance t o neurotic or psychotic illness with borderline syndromes forming a class of disturbances sitting between full-blown psychosis, neurosis and the personality variations that predispose to them.

In the first chapters of the book, Claridge proceeds from a discussion of dimensions of temperament, nervous types, and the inheritance of dispositions to an explanation of dysthymic neuroses (phobias, compulsions, neurotic depressions) and more extraverted forms of disturbance (fugues, rogues and histrionics). The dimensions of temperament upon which Claridge bases his arguments mainly comprise Eysenck’s extraversion-introversion, neuroticism and psychoticism traits, Gray’s dimensions of anxiety and impulsivity and Zuckerman’s concepts of sensation-seeking and augmenting-reducing. Claridge emphasises that these dimensions of temperament should not be overlooked in explanations of mental illness, but naturally cannot give a complete account of personality nor of the disorders that arise from them. The chapter on nervous systems is mainly influenced by Pavlov and researchers working in his tradition. Claridge stresses that such theories are limited by paying too little attention to higher nervous functions. For clinical psychologists, the chapters on introverted and extraverted forms of neurotic and personality disorders are most informative since the author tries to answer the difficult question of differential etiology: What determines the form of mental illness from which particular people suffer? Oriented towards an integrative etiological perspective Claridge combines biological arguments with concepts from learning theory, stress research and cognitive psychology (and sometimes even psychoanalysis).

The second part of the book is dedicated to the more severe forms of psychopathology; the psychoses (especially the schizophrenias) and the borderline syndromes. Here the argumentation proceeds downwards from symptoms to etiology. Since searching for the ‘psychotic nervous type’ has preoccupied Claridge for two decades, it is not surprising that these chapters contain a rich collection of valuable clinical material and experimental

0 1988 by John Wiley & Sons, Ltd.

170 Book review

research. The main thesis says that even for psychosis (mainly schizophrenia) there are continuous variations from normality to extreme forms of disturbance. Claridge gives a comprehensive overview on attempts to establish an ‘experimental psychopathology’ and a differential psychology of schizophrenia. He stresses that a crucial feature of the psychotic brain is the loosening, or relative failure, of its homeostatic regulation, and that this explains the extreme variability of psychotic behaviour. Most interesting is the thesis that homeostatic dysregulation not only refers to the vertical or hierarchical but also to the horizontal organization of brain processes. Reviewing a rapidly growing branch of experimental research, Claridge is optimistic that studying the differential functions of the two brain hemispheres will throw some light on disturbed higher nervous processes in schizophrenic patients. At present, the empirical results are difficult to integrate and some hypotheses are diametrically opposed to each other.

For personality psychologists, Claridge’s well-founded critique of Eysenck’s psychoticism dimension is most informative. The author hopes to get nearer to the temperamental basis of psychotic tendencies by developing two new questionnaire scales based on the symptoms of ‘schizotypal personality disorder’ and ‘borderline personality disorder’. Unfortunately, the reader is not informed about the psychometric qualities of these scales and their correlations with Eysenck’s psychoticism scale. So it is not clear whether these new scales tap at the same personality dimension as Eysenck’s psychoticism scale. It may also be doubted whether measures based on symptoms actually deepen our understanding of the basic personality structure of psychotic patients in a noncircular manner.

What about the strengths and weaknesses of the book? It is unique in bringing into contact two disciplines of psychology, personality psychology and clinical psychology, which undoubtedly may profit a lot from each other. After reading the book one gets the firm impression that experimental and genetic research on the temperamental basis of interindividual differences in behaviour should not be overlooked by clinical psychologists trying to explain and to modify abnormal behaviour. Most valuable are those passages in the book where the author integrates personality psychological knowledge with insights from learning theory, family psychology, stress research and psychoanalysis. One might have appreciated even more passages of this type in the book.

Inevitably, some omissions and wants of clearness have to be mentioned. Neither Cattell nor Millon are cited in the book, although both have made some major contributions to the field. Research on the stability of temperamental variables is not considered. Claridge does not discuss whether the high variability in psychotic behaviour to some extent may be an artefact of medication. Readers interested in the therapeutic consequences of the kind of research described in the book get little help from Claridge. The tenor of the book is apt to dampen too much optimism that adult behaviour is easy to alter. For the personality psychologist it remains unclear whether Eysenck’s psychoticism dimension should still be regarded as a temperamental trait characteristic of psychotic patients or whether it should be replaced by a new construct based on new operationalizations. One may regret that Claridge does not include the personality dimensions of intelligence (or coping competencies) among those traits interacting with temperamental dispositions and environmental demands and resources in determining normal or abnormal behavior. One of the main theses of the book would be strengthened if more longitudinal research could be cited showing that certain combinations of premorbid temperamental traits indeed increase the risk of developing particular forms of mental illness. Since such research is very difficult to realize, a partial test of the thesis could be performed by studying the temperamental traits and biological processes of former psychiatric patients during periods of remission.

Concluding, Origins of Mental Illness is a most informative book apt to deepen our understanding of psychopathology by pointing t o some of its important temperamental bases. It deserves to be studied by all people seriously interested in an integrative view of mental illness.

P E T E R B E C K E R University of Trier, FRG