- Email: [email protected]
A study on the origins of mental retardation
462
BOOK REVIEWS
A Study on the Origins of Mental Retardation (Clinics in Developmental Medicine. No. 51), by M. IIVANAINEN. X--173 pages. 56 illustrations. 51 tables, appendices. Spastics International Medical Publications. 1974. available from HeinemannMedical Books. Tadworth, Surrey, and Lippincott, Philadelphia, Pa., £4.40.
The strengths of this study are the range o f the author's reading (Chapter 1~, and the meticulousness of his m e a s u r e m e n t of neurophysiotogical variables. For these alone, the book is well worth buying as a source of references. However, the literature review itseff shows that the present study was unlikely to contribute either to prevention of further cases or to treatment of existing cases of mental retardation. The author poses two questions. As interpreted by the reviewer they are : {1) Given clinical and aetiological data on mentally retarded people, bow do these correlate ? {2) Given clinical and aetiological data without neuro-radiological data. what additional information on aetiology can be obtained by means of neuro-radiological investigations? These questions were posed in "the belief that the successful treatment and prophylaxis in, cases of mental retardation depend on an understanding of the aetiology and clinical signs" (p. 171 Selection of cases The author selected 880 patients still alive from a m o n g the 1000 who had been admitted to the Rinnekoti Institution over 23 years before 196Z Following physical, cytogenetic. EEG and echoencephalographic investigauons. 368 were selected for neuro-radiological investigation on the basis that pneumoencephalography and cerebral angiography were indicated, or rather not contra-indirated. Parent permission was obtained for 338 patients. The so-called indications a m o n g those selected were: epilepsy with or without cerebral palsy (60~o}, malformation (17%); cerebral palsy (12°o), EEG abnormality alone (3°:g), large head ( 2 ~ ) , miscellaneous 6 /o,/ . The patients selected ranged in age from 1 to 49 years old and 94°0 had IQ < 52. Data collection The following procedures were carried out on the 338 people: (1) Historical information 21 items. (2) Physical examination 53 items. {3) IQ test scores. (4) Functional behavioural ratings. (5) Cerebrospinal fluid examinations. (6) Laboratory tests - biochemical - 10 items. (7] C h r o m o s o m e - venous blood 123 cases skin ? smears 15cases.
(8} Auditory evoked potentials ~>.~cases IP. 22) or 94 cases (p. 41 I. 191EEG 583 records on 323 cascy. {10] Skull X-rays 4 views on 331 cases selma turcica pictures-- 323 cases - cranial volume - 286 cases,
( I 1 ) Echoencephalography 7t) cases, [12} Cerebral angiography 90 cases !under general anaesthesia). (13) Pneumoencephalography 334 cases lunder general anaesthesia ). {14) Brain scanning 5 cases lunder general anaesthesia). (151 Neuropathologtcal investigatmns 6 cases [under general anaesthesiak Manipulations oJ data collected In each o f the 338 cases, the author (Chapter 4J inferred from the above data the "'primary aetiotogy'" o f the mental retardation. He then ascribed the case to one of 5 categories {Yannet t 945) relating to the likely time of the brain damage [prenatal 450,.0 : perinatal 12°'o: postnatal 18~':,: more than category 5"/, undeterminable 20" ~) and to one of 10 categories ( W H O 1968. following Heber 1961) (Infection and Intoxication 17 ° : T r a u m a or Physical Agents 14".-o , Disorders of Metabolism 3°<'o, Gross Brain Disease 3"~,; U n k n o w n Perinatal Influence . 1o, , . C h r o m o s o m e Aberrations 4 , Prematurity t~ o; Major Psychiatric Disorder 0: More than one Probable Cause "' Other and Unspecified Causes 20"~,). No details are given of ho~ the cases were allocated to the Yannet categories, and there is no complete cross-tabulation of the two classification systems. This presents the reader with problems m interpreting the subsequent correlations which are presented according to both classifications. The classification involved selectior~ from and appraisal of the historical data (pp. 28 and 58-64'1 and despite the author's plea for standardisation of cnterta, no reliability figures are given. In addition, it is acknowledged on p. 116 that neuro-radiological and other clinical data were used in arriving at the aetiological categories. This leads to problems of interpretation later when the aetiologicat categories are treated as independent variables with clinical and neuro-radiological signs as dependent variables. No reliability data or criteria for radiological classification are presented either, The author [p. 20} is aware of the weaknesses ol
BOOK REVIEWS
the historical data abstracted from case records, interviews and questionnaires to relatives (not described). Having mentioned these weaknesses they are not referred to later when results confirm the author's predictions (p. 30-31) but are referred to in order explain inconsistencies with the author's main arguments (p. 27). The cases had been classified prior to this study according to Heber (1961). After his additional investigations the author reclassified 196 cases (p. 102). Again, no details are presented on the reliability (repeatability) of the reclassification, or on the characteristics of the reclassified cases. However, cases originally categorised: " T r a u m a or physical agents" were reduced from 28% to 15~'/o; "'Uncertain cause with functional reaction alone manifest" (i.e. without observable signs of neurological abnormality) were reduced from 1 2 ~ to 1%; "Uncertain cause with structural reactions manifest" (i.e. with observable signs of neurological abnormality) were increased from 1 8 ~ to 220/o; "'Unknown pre-natal influence" were increased from 21% to 370/o. Conclusions The author concludes that with respect to people for whom "the aetiology had been completely unknown .... the finding that the majority had suffered cerebral insult before birth was in itself an important stepfi~rward*. It is to be hoped that, with more careful studies of babies in the perinatal period and more detailed collection of historical data, we shall, in future, be able to make more definite diagnoses of the causes of some of these pathological conditions". (p. 102). Since no treatment or preventive procedures can be undertaken as a result of collecting the data, the relevance of its collection remains obscure. The author concludes (p. 146) with the following advice : (i) other scientists and clinicians should undertake studies of this sort; (ii) in addition to the investigations recommended by Richards (1963) to be undertaken in individual cases of mental retardation "every available m o d e m technique.., such as chromatography, cytogenetic studies..." the author recommends that "neuro-radiological studies should be added" and that investigations should be performed as early as possible "to ensure that they are of the greatest possible benefit to the patient himself". Thus the therapist will be able to choose suitable treatment or rehabilitation; and given such an "understanding of the causes of mental retardation" the doctor can provide the patients with "deft'niter' information as to theprobable ~' cause of their child;s retardation". The parents "are more likely to have
*Reviewer's emphasis.
463
confidence in him and less likely.., to spend time and money going from doctor to doctor or from quack to quack in search of an answer". However, it is not evident from this study that the above is true. Only one individual a m o n g the 338 studied received treatment as a result of a finding revealed by this battery of investigations: a boy aged 14 (p. 88) retarded from infancy: "At the time of the investigation he was having ten to twenty fits per month, and had transient ataxia (due to phenytoin intoxication) and dysphasia. Subsequent to the present investigations a grade II astrocytoma has been removed and the boy's condition has improved markedly". On these indications, however, this boy would appear to be one of the few for whom full investigation ought to be done in any case; he hardly justifies pneumoencephalography for everyone. The data presented in the review had shown clearly that it would be possible to detect brain pathology in 80-90% of severely retarded subjects. What additional aetiological data was likely to be obtained from the neuroradiological investigations ? If these data could not have been used in treating individuals, could they have been helpful in preventing future cases arising? As shown in many studies reviewed by the author, and in an important study that he does not mention (Berg and Kirman 1959), preventable causes can be definitely identified as causal in only a small proportion of clients, and then only after the event. The author's own literature review should also have made it clear that treatment and care of individual patients is very seldom made more effective or specific by identifying the detailed morphology, the pathology, the time period at which the cerebral insult took place, or the causal agent responsible for the neuropathology in the few patients in w h o m this can be identified. There are now available effective forms of educational care and treatment of people with behavioural deficits and excesses. These educational methods do not depend on detailed knowledge of the neuro-pathology or of the history. However. their effectiveness does depend on correction of correctable organic defects which seriously limit adaptive responses, e. 9. vision and hearing defects, contractures, convulsions and correctable metabolic disorders. Their effectiveness also depends on the availability of rich social and physical environments in which existing skills can be maintained and developed. On the one hand, given barren environments with little material to contact and few adults with whom to interact, useful skills will be lost and disagreeable skills will be acquired by many patients irrespective of their neuropathology or their histories. Money spent on staff and technical equipment to identify neuropathology and infer aetiology
464
BOOK REVIEWS
cannot also be spent to educate people who have neuropathological lesions, or on stall" or equtpmerit to remedy the long-term effects of the pathology. Instead. the barren environments may not even allow patients to wear hearing-aids or spectacles or to use walking aids. This seems to be true in Finland as well as Britain: for example, the 4~ million total population served by the Rinnekoti Hospital appears to have only 20 residential places and 16 day care places per 100,000 total population [p. 20). In Britain the recommendations for each type of prowsion are around 150 per 100,000 total population. A low nurse-pauent ratio ~s suggested both by the description of methods of acquiring the very scanty data on the functional ability of the subjects and the author's anxieties about its usefulness (P. 21 ). ]'he lack of staff to assess the clients' sight and hearing in the ordinary living environment led to the use of the sophisticated but mapproprmte method of Auditory Evoked Potential. The lack of psychiatric data is highlighted and psychiatric manifestations of behaviour are confused with "causes" (p. 1441 It seems reasonable to speculate that it ~s unsausfactory "treatment" environments and unhelpful advice that sends patients searching for help "from doctor to doctor or from quack to q u a c k (p. 146). The investigations undertaken also ratse the problem of "informed consent". The indications for neuro-radiological investigations quoted in the literature review appear to be related to a high probability that treatable organic conditions are present. Indeed. with respect to pneumo-encephalographic investigations, Spitz et al. {1962} are quoted on p. 13 as saying that the patient should have lived for "a minimum of 9 m o n t h s . . i n an environment oftherapeutically oriented group living". The author seems to see no need for safeguards against possible abuse by clinicians or scientists motivated by curiosity. Nor do the statistical associations reported help to clarify any outstanding scientific issues. The reviewer found much of the discussion of these associations confusing and this was compounded by the problem of inter-relating the Yannet and WHO categories. Much of the discussion is highly speculative and does not appear to present leads towards fruitful research, therapy or preventive action. In Chapter 3 the results for each item are compared either with results for some sample of the normal Finnish people or with results of other surveys of mental retardation. Often. where results appear to disagree with the author's predictions, he infers that this is likely to be due to "selection" or to "'unreliability of parental informants". Where results appear to agree, these problems are not mentioned. Thus (p. 261 a family history of retar-
dation ~s regarded as agreemg well with Penrose [ 1938 ) - no mention is made of whether the relative~ are mildly retarded or severely retarded although this is likely to affect the interpretation of the data. Similarly. (p. 27) despite the fact that evidence of abnormalities during pregnancy was only sought when the abnormalities were likely to be ot causal significance, toxaemm is reported as significantly more frequent than among the general population of Finnish mothers. In Chapter 4, the author has reduced the number of cases in which toxaemia is likely to have been causal from 55 to 15 tpp. 5" and 89). Elsewhere (p. 1421 the author appears to be unaware of the possibility that differences might be due to selection of different proportions of mildly and severely retarded subject. The data on low birthweight Ip. 22j are said to agree well with other studies but are difficult to interpret. Drittien [1968)and McDonald 11967) have shown increased prevalence of severe retardation at birthweight less than 1800 g but here the lowest birthweight category is 2500 g or tess. [n Chapter 5 the findings are presented of the associauons between the categories of the Yannel and WHO aetiological classifications and each of the dependent variables. These results are discussed systematically in Chapter 6. Many of the resulting correlations are difficult to interpret and the speculations offered are inconsistent, even when credible; see for example the guesses about unmarried mothers on pp. 108 and 128 When researchers collect data on large numbers of individuals, average them. and manipulate them statistically in search of relationships between independent and dependent variables, spuriou~ correlations may be generated, and genuinely important ones may be obscured. This is more likely to occur when the variables are composite indices for very complex characteristics, and when the categories used are composttes or complexes of suheategories. The aetiologtcal categories used by the author have these feature~ It would be useful if the a u t h o r s very considerable skills in data collection might in future be harnessed to solving clearly defined research or clinical probIems. Until such problems are more clearly defined il would be in everyone's mterest not to collect routinely more data of this type. These procedures, in addition to involving the patients in considerable inconvenience and discomfort Isee p. 78 for a description of head shaving to identify possible cases of curls verticts gyrata) if not risks tP, 1421, also divert resources and stall effort from the prtmary task of arranging the environment of handicapped people to maintain and develop their behavioural repertoires. AI.BER t ]'~USHIA~ K
BOOK REVIEWS REFERENCES BERG, J. M. AND B. H. KIRMAN(1959) Some aetiological problems in mental deficiency, Brit. reed. J., 2:848 852. DR1LLIEN, C. M. (1968) Studies in mental handicap, Part 2 (Some obstetric factors of possible aetiological importance), Arch. Dis. Childh., 43 : 283. HEBER, R. (1961) A Manual on Terminolooy and Classification in Mental Retardation, Monograph No. 2 of Amer. J. ment. Deficiency, Vol. 66. McDONALD, A. (1967) Children o f Very Low Birth Weiyht A Survey of1128 Children with a Birth Weight o/'4 lb (1800 9) or Less (Research Monograph, No. 1 ), Spastics Society with Heinemann Medical, London.
465
PENROSE, L. S. (1938)A Clinical and Genetic Stud), of 1280 Cases o f Mental Defect ( M R C Special Report Series, No. 229), Her Majesty's Stationery Office, London. R1CHARDS, B. W. (1963) Mental retardation Methods of diagnosis and some recently described syndromes, Canad. reed. Ass'. J., 89: 1024. SPITZ, E. B., W. C. ADAMSONAND W. L. NOE (1962) Criteria for pneumoencephalography in differential diagnostic study of mental subnormality, Amer. J. ment. Deficiency, 66: 561. WORLD HEALTH ORGANIZATION (1948, 1968) The International Classification o f Diseases, World Health Organization, Geneva. YANNET, H. (1945) Diagnostic classification of patients with mental deficiency, Amer. J. Dis. Child., 70: 83.
Roentyen Diaonosis of the Craniovertebral Reyion, by A. WACrO~NHEIM,xxii+601 pages, 500 illustrations, Springer-Verlag, Berlin, Heidelberg, New York, 1974, DM 368.00, US$ 150.20. What a beautifully illustrated book this is! The logical first reaction of an editor was to pass it for review to a colleague working in neuroradiology, but the more emotional second reaction of a neurologist was to possess it personally as a work of reference, so that ultimately emotion triumphed over logic. This is a typically superb Springer production, clearly printed and logically arranged. With 500 illustrations (clinical photographs, diagrams and above all superb reproductions of radiographs) and over 1000 references, Professor Wackenheim has contributed a volume on the radiology of the cra-
nio-vertebral junction which is sure to have a firm and favoured place in all of those neurological and neuroradiological reference libraries which can afford it. The text is clear and concise, if at times controversial (conventional pneumoencephalography is dismissed in two lines as being valueless and there are other idiosyncrasies which may arouse dispute a m o n g neuroradiologists). Nevertheless, the book is a mine of verbal and visual information and " A thing of beauty".
JOHN N. WALTON
Central Nervous System - - Studies on Metabolic Reyulation and Function (based on Symposium on Metabolic Regulation and Functional Activity in the Central Nervous System, 16-17 September, 1972, Aosta, Italy), by E. GENAZZANIAND H. HERKEN (Eds.), viii + 249 pages, 121 illustrations, 55 tables, Springer-Verlag, Berlin, Heidelberg, New York, 1974, DM 79.00, US$ 30.50. This book comprises the papers read at a symposium on metabolic regulation and functional activity in the central nervous system which was held at St.-Vincent, Italy in September 1972, and was sponsored by the Accademia di Medicina di Torino. The object of the symposium was to cover the general field of the relationship between metabolism and function, and to provide a forum for scientists from m a n y c o u n t r i e s to present their latest research. As it transpired most of the participants were from Italy and France, a small number
coming from other European countries and the U.S.A. The editors say that they intended to avoid consideration of topics in detail, but it would perhaps be more accurate to say that each paper provides a fairly detailed consideration of its own topic, but there is no more than one paper on each topic. The papers are divided into three groups, the first dealing with metabolic pathways in relation to central nervous function. The second relates to membrane function and neurotransmission. In fact
BOOK REVIEWS
A Study on the Origins of Mental Retardation (Clinics in Developmental Medicine. No. 51), by M. IIVANAINEN. X--173 pages. 56 illustrations. 51 tables, appendices. Spastics International Medical Publications. 1974. available from HeinemannMedical Books. Tadworth, Surrey, and Lippincott, Philadelphia, Pa., £4.40.
The strengths of this study are the range o f the author's reading (Chapter 1~, and the meticulousness of his m e a s u r e m e n t of neurophysiotogical variables. For these alone, the book is well worth buying as a source of references. However, the literature review itseff shows that the present study was unlikely to contribute either to prevention of further cases or to treatment of existing cases of mental retardation. The author poses two questions. As interpreted by the reviewer they are : {1) Given clinical and aetiological data on mentally retarded people, bow do these correlate ? {2) Given clinical and aetiological data without neuro-radiological data. what additional information on aetiology can be obtained by means of neuro-radiological investigations? These questions were posed in "the belief that the successful treatment and prophylaxis in, cases of mental retardation depend on an understanding of the aetiology and clinical signs" (p. 171 Selection of cases The author selected 880 patients still alive from a m o n g the 1000 who had been admitted to the Rinnekoti Institution over 23 years before 196Z Following physical, cytogenetic. EEG and echoencephalographic investigauons. 368 were selected for neuro-radiological investigation on the basis that pneumoencephalography and cerebral angiography were indicated, or rather not contra-indirated. Parent permission was obtained for 338 patients. The so-called indications a m o n g those selected were: epilepsy with or without cerebral palsy (60~o}, malformation (17%); cerebral palsy (12°o), EEG abnormality alone (3°:g), large head ( 2 ~ ) , miscellaneous 6 /o,/ . The patients selected ranged in age from 1 to 49 years old and 94°0 had IQ < 52. Data collection The following procedures were carried out on the 338 people: (1) Historical information 21 items. (2) Physical examination 53 items. {3) IQ test scores. (4) Functional behavioural ratings. (5) Cerebrospinal fluid examinations. (6) Laboratory tests - biochemical - 10 items. (7] C h r o m o s o m e - venous blood 123 cases skin ? smears 15cases.
(8} Auditory evoked potentials ~>.~cases IP. 22) or 94 cases (p. 41 I. 191EEG 583 records on 323 cascy. {10] Skull X-rays 4 views on 331 cases selma turcica pictures-- 323 cases - cranial volume - 286 cases,
( I 1 ) Echoencephalography 7t) cases, [12} Cerebral angiography 90 cases !under general anaesthesia). (13) Pneumoencephalography 334 cases lunder general anaesthesia ). {14) Brain scanning 5 cases lunder general anaesthesia). (151 Neuropathologtcal investigatmns 6 cases [under general anaesthesiak Manipulations oJ data collected In each o f the 338 cases, the author (Chapter 4J inferred from the above data the "'primary aetiotogy'" o f the mental retardation. He then ascribed the case to one of 5 categories {Yannet t 945) relating to the likely time of the brain damage [prenatal 450,.0 : perinatal 12°'o: postnatal 18~':,: more than category 5"/, undeterminable 20" ~) and to one of 10 categories ( W H O 1968. following Heber 1961) (Infection and Intoxication 17 ° : T r a u m a or Physical Agents 14".-o , Disorders of Metabolism 3°<'o, Gross Brain Disease 3"~,; U n k n o w n Perinatal Influence . 1o, , . C h r o m o s o m e Aberrations 4 , Prematurity t~ o; Major Psychiatric Disorder 0: More than one Probable Cause "' Other and Unspecified Causes 20"~,). No details are given of ho~ the cases were allocated to the Yannet categories, and there is no complete cross-tabulation of the two classification systems. This presents the reader with problems m interpreting the subsequent correlations which are presented according to both classifications. The classification involved selectior~ from and appraisal of the historical data (pp. 28 and 58-64'1 and despite the author's plea for standardisation of cnterta, no reliability figures are given. In addition, it is acknowledged on p. 116 that neuro-radiological and other clinical data were used in arriving at the aetiological categories. This leads to problems of interpretation later when the aetiologicat categories are treated as independent variables with clinical and neuro-radiological signs as dependent variables. No reliability data or criteria for radiological classification are presented either, The author [p. 20} is aware of the weaknesses ol
BOOK REVIEWS
the historical data abstracted from case records, interviews and questionnaires to relatives (not described). Having mentioned these weaknesses they are not referred to later when results confirm the author's predictions (p. 30-31) but are referred to in order explain inconsistencies with the author's main arguments (p. 27). The cases had been classified prior to this study according to Heber (1961). After his additional investigations the author reclassified 196 cases (p. 102). Again, no details are presented on the reliability (repeatability) of the reclassification, or on the characteristics of the reclassified cases. However, cases originally categorised: " T r a u m a or physical agents" were reduced from 28% to 15~'/o; "'Uncertain cause with functional reaction alone manifest" (i.e. without observable signs of neurological abnormality) were reduced from 1 2 ~ to 1%; "Uncertain cause with structural reactions manifest" (i.e. with observable signs of neurological abnormality) were increased from 1 8 ~ to 220/o; "'Unknown pre-natal influence" were increased from 21% to 370/o. Conclusions The author concludes that with respect to people for whom "the aetiology had been completely unknown .... the finding that the majority had suffered cerebral insult before birth was in itself an important stepfi~rward*. It is to be hoped that, with more careful studies of babies in the perinatal period and more detailed collection of historical data, we shall, in future, be able to make more definite diagnoses of the causes of some of these pathological conditions". (p. 102). Since no treatment or preventive procedures can be undertaken as a result of collecting the data, the relevance of its collection remains obscure. The author concludes (p. 146) with the following advice : (i) other scientists and clinicians should undertake studies of this sort; (ii) in addition to the investigations recommended by Richards (1963) to be undertaken in individual cases of mental retardation "every available m o d e m technique.., such as chromatography, cytogenetic studies..." the author recommends that "neuro-radiological studies should be added" and that investigations should be performed as early as possible "to ensure that they are of the greatest possible benefit to the patient himself". Thus the therapist will be able to choose suitable treatment or rehabilitation; and given such an "understanding of the causes of mental retardation" the doctor can provide the patients with "deft'niter' information as to theprobable ~' cause of their child;s retardation". The parents "are more likely to have
*Reviewer's emphasis.
463
confidence in him and less likely.., to spend time and money going from doctor to doctor or from quack to quack in search of an answer". However, it is not evident from this study that the above is true. Only one individual a m o n g the 338 studied received treatment as a result of a finding revealed by this battery of investigations: a boy aged 14 (p. 88) retarded from infancy: "At the time of the investigation he was having ten to twenty fits per month, and had transient ataxia (due to phenytoin intoxication) and dysphasia. Subsequent to the present investigations a grade II astrocytoma has been removed and the boy's condition has improved markedly". On these indications, however, this boy would appear to be one of the few for whom full investigation ought to be done in any case; he hardly justifies pneumoencephalography for everyone. The data presented in the review had shown clearly that it would be possible to detect brain pathology in 80-90% of severely retarded subjects. What additional aetiological data was likely to be obtained from the neuroradiological investigations ? If these data could not have been used in treating individuals, could they have been helpful in preventing future cases arising? As shown in many studies reviewed by the author, and in an important study that he does not mention (Berg and Kirman 1959), preventable causes can be definitely identified as causal in only a small proportion of clients, and then only after the event. The author's own literature review should also have made it clear that treatment and care of individual patients is very seldom made more effective or specific by identifying the detailed morphology, the pathology, the time period at which the cerebral insult took place, or the causal agent responsible for the neuropathology in the few patients in w h o m this can be identified. There are now available effective forms of educational care and treatment of people with behavioural deficits and excesses. These educational methods do not depend on detailed knowledge of the neuro-pathology or of the history. However. their effectiveness does depend on correction of correctable organic defects which seriously limit adaptive responses, e. 9. vision and hearing defects, contractures, convulsions and correctable metabolic disorders. Their effectiveness also depends on the availability of rich social and physical environments in which existing skills can be maintained and developed. On the one hand, given barren environments with little material to contact and few adults with whom to interact, useful skills will be lost and disagreeable skills will be acquired by many patients irrespective of their neuropathology or their histories. Money spent on staff and technical equipment to identify neuropathology and infer aetiology
464
BOOK REVIEWS
cannot also be spent to educate people who have neuropathological lesions, or on stall" or equtpmerit to remedy the long-term effects of the pathology. Instead. the barren environments may not even allow patients to wear hearing-aids or spectacles or to use walking aids. This seems to be true in Finland as well as Britain: for example, the 4~ million total population served by the Rinnekoti Hospital appears to have only 20 residential places and 16 day care places per 100,000 total population [p. 20). In Britain the recommendations for each type of prowsion are around 150 per 100,000 total population. A low nurse-pauent ratio ~s suggested both by the description of methods of acquiring the very scanty data on the functional ability of the subjects and the author's anxieties about its usefulness (P. 21 ). ]'he lack of staff to assess the clients' sight and hearing in the ordinary living environment led to the use of the sophisticated but mapproprmte method of Auditory Evoked Potential. The lack of psychiatric data is highlighted and psychiatric manifestations of behaviour are confused with "causes" (p. 1441 It seems reasonable to speculate that it ~s unsausfactory "treatment" environments and unhelpful advice that sends patients searching for help "from doctor to doctor or from quack to q u a c k (p. 146). The investigations undertaken also ratse the problem of "informed consent". The indications for neuro-radiological investigations quoted in the literature review appear to be related to a high probability that treatable organic conditions are present. Indeed. with respect to pneumo-encephalographic investigations, Spitz et al. {1962} are quoted on p. 13 as saying that the patient should have lived for "a minimum of 9 m o n t h s . . i n an environment oftherapeutically oriented group living". The author seems to see no need for safeguards against possible abuse by clinicians or scientists motivated by curiosity. Nor do the statistical associations reported help to clarify any outstanding scientific issues. The reviewer found much of the discussion of these associations confusing and this was compounded by the problem of inter-relating the Yannet and WHO categories. Much of the discussion is highly speculative and does not appear to present leads towards fruitful research, therapy or preventive action. In Chapter 3 the results for each item are compared either with results for some sample of the normal Finnish people or with results of other surveys of mental retardation. Often. where results appear to disagree with the author's predictions, he infers that this is likely to be due to "selection" or to "'unreliability of parental informants". Where results appear to agree, these problems are not mentioned. Thus (p. 261 a family history of retar-
dation ~s regarded as agreemg well with Penrose [ 1938 ) - no mention is made of whether the relative~ are mildly retarded or severely retarded although this is likely to affect the interpretation of the data. Similarly. (p. 27) despite the fact that evidence of abnormalities during pregnancy was only sought when the abnormalities were likely to be ot causal significance, toxaemm is reported as significantly more frequent than among the general population of Finnish mothers. In Chapter 4, the author has reduced the number of cases in which toxaemia is likely to have been causal from 55 to 15 tpp. 5" and 89). Elsewhere (p. 1421 the author appears to be unaware of the possibility that differences might be due to selection of different proportions of mildly and severely retarded subject. The data on low birthweight Ip. 22j are said to agree well with other studies but are difficult to interpret. Drittien [1968)and McDonald 11967) have shown increased prevalence of severe retardation at birthweight less than 1800 g but here the lowest birthweight category is 2500 g or tess. [n Chapter 5 the findings are presented of the associauons between the categories of the Yannel and WHO aetiological classifications and each of the dependent variables. These results are discussed systematically in Chapter 6. Many of the resulting correlations are difficult to interpret and the speculations offered are inconsistent, even when credible; see for example the guesses about unmarried mothers on pp. 108 and 128 When researchers collect data on large numbers of individuals, average them. and manipulate them statistically in search of relationships between independent and dependent variables, spuriou~ correlations may be generated, and genuinely important ones may be obscured. This is more likely to occur when the variables are composite indices for very complex characteristics, and when the categories used are composttes or complexes of suheategories. The aetiologtcal categories used by the author have these feature~ It would be useful if the a u t h o r s very considerable skills in data collection might in future be harnessed to solving clearly defined research or clinical probIems. Until such problems are more clearly defined il would be in everyone's mterest not to collect routinely more data of this type. These procedures, in addition to involving the patients in considerable inconvenience and discomfort Isee p. 78 for a description of head shaving to identify possible cases of curls verticts gyrata) if not risks tP, 1421, also divert resources and stall effort from the prtmary task of arranging the environment of handicapped people to maintain and develop their behavioural repertoires. AI.BER t ]'~USHIA~ K
BOOK REVIEWS REFERENCES BERG, J. M. AND B. H. KIRMAN(1959) Some aetiological problems in mental deficiency, Brit. reed. J., 2:848 852. DR1LLIEN, C. M. (1968) Studies in mental handicap, Part 2 (Some obstetric factors of possible aetiological importance), Arch. Dis. Childh., 43 : 283. HEBER, R. (1961) A Manual on Terminolooy and Classification in Mental Retardation, Monograph No. 2 of Amer. J. ment. Deficiency, Vol. 66. McDONALD, A. (1967) Children o f Very Low Birth Weiyht A Survey of1128 Children with a Birth Weight o/'4 lb (1800 9) or Less (Research Monograph, No. 1 ), Spastics Society with Heinemann Medical, London.
465
PENROSE, L. S. (1938)A Clinical and Genetic Stud), of 1280 Cases o f Mental Defect ( M R C Special Report Series, No. 229), Her Majesty's Stationery Office, London. R1CHARDS, B. W. (1963) Mental retardation Methods of diagnosis and some recently described syndromes, Canad. reed. Ass'. J., 89: 1024. SPITZ, E. B., W. C. ADAMSONAND W. L. NOE (1962) Criteria for pneumoencephalography in differential diagnostic study of mental subnormality, Amer. J. ment. Deficiency, 66: 561. WORLD HEALTH ORGANIZATION (1948, 1968) The International Classification o f Diseases, World Health Organization, Geneva. YANNET, H. (1945) Diagnostic classification of patients with mental deficiency, Amer. J. Dis. Child., 70: 83.
Roentyen Diaonosis of the Craniovertebral Reyion, by A. WACrO~NHEIM,xxii+601 pages, 500 illustrations, Springer-Verlag, Berlin, Heidelberg, New York, 1974, DM 368.00, US$ 150.20. What a beautifully illustrated book this is! The logical first reaction of an editor was to pass it for review to a colleague working in neuroradiology, but the more emotional second reaction of a neurologist was to possess it personally as a work of reference, so that ultimately emotion triumphed over logic. This is a typically superb Springer production, clearly printed and logically arranged. With 500 illustrations (clinical photographs, diagrams and above all superb reproductions of radiographs) and over 1000 references, Professor Wackenheim has contributed a volume on the radiology of the cra-
nio-vertebral junction which is sure to have a firm and favoured place in all of those neurological and neuroradiological reference libraries which can afford it. The text is clear and concise, if at times controversial (conventional pneumoencephalography is dismissed in two lines as being valueless and there are other idiosyncrasies which may arouse dispute a m o n g neuroradiologists). Nevertheless, the book is a mine of verbal and visual information and " A thing of beauty".
JOHN N. WALTON
Central Nervous System - - Studies on Metabolic Reyulation and Function (based on Symposium on Metabolic Regulation and Functional Activity in the Central Nervous System, 16-17 September, 1972, Aosta, Italy), by E. GENAZZANIAND H. HERKEN (Eds.), viii + 249 pages, 121 illustrations, 55 tables, Springer-Verlag, Berlin, Heidelberg, New York, 1974, DM 79.00, US$ 30.50. This book comprises the papers read at a symposium on metabolic regulation and functional activity in the central nervous system which was held at St.-Vincent, Italy in September 1972, and was sponsored by the Accademia di Medicina di Torino. The object of the symposium was to cover the general field of the relationship between metabolism and function, and to provide a forum for scientists from m a n y c o u n t r i e s to present their latest research. As it transpired most of the participants were from Italy and France, a small number
coming from other European countries and the U.S.A. The editors say that they intended to avoid consideration of topics in detail, but it would perhaps be more accurate to say that each paper provides a fairly detailed consideration of its own topic, but there is no more than one paper on each topic. The papers are divided into three groups, the first dealing with metabolic pathways in relation to central nervous function. The second relates to membrane function and neurotransmission. In fact