Known And Unknown Causes Of Mental Handicap

Press, Volume CIII, Issue 30541, 9 September 1964, Page 24

Known And Unknown Causes Of Mental Handicap

(CONTRIBUTED) President Kennedy, in 1962, when appointing the President’s Panel on Mental Retardation, said: “Both wisdom and humanity dictate a deep interest in the physically handicaped, the mentally ill and the mentally retarded. Yet, although we have made considerable progress in the treatment of physical handicaps, although we have attacked, on a broad front, the problems of mental illness, although we have made great strides in the battle against disease, we, as a nation, have far too long postponed an intensive search for solutions to the problems of the mentally retarded. That failure should be corrected. Our obligation is to search for the secret of the human mind and to share our knowledge with the world.”

What is- meant by mental retardation or intellectual handicap, as we call it in this country? What causes it? How common is it?

It means the impairment of intellectual functioning as the result of structural or biochemical abnormality of the brain, together with impaired social adaptation. The term is a descriptive one and consideration of its causes embraces a wide field of medicine, although at the present time, the precise cause can be stated in only the minority of cases. There are probably 5000 to 7000 I.H. children and adults in New Zealand today and another 200 to 250, say three per thousand, bom each year. Nor do these figures include the mildly retarded, who number 10 times as many but who mostly achieve independence. Good Homes And Bad

Nor does intellectual handicap strike only a certain type of family; the I.H. child is to be-found in good homes and- in bad, in the homes of the well-to-do and of the poor, of the famous and of the obscure, of the well-educated and of. the ignorant. He is born to careful, devoted parents as well as to careless, lazy and indifferent parents, into small families and into large families, into any sort of family at all. The causes of intellectual handicap can facetiously be divided into two—the known and the unknown. Probably all causes are genetic or environmental, the latter composed of those causes operating before birth, those operating at birth, those operating in childhood and in later life. Standards of living and individual patterns of living are rare environmental causes of intellectual handicap in this country, although older maternal age and poor maternal health may increase the chances of prematurity, and the really premature baby is more likely to be physically and mentally handicapped. The role, during pregnancy, of drugs and illnesses causing intellectual and physical handicap is well known, particularly of certain infectious fevers like German measles, which, infecting early in pregnancy women who have not previously had the dis-

ease, may produce blindness, deafness, heart disease, intellectual handicap or a combination of them. The intelligent and restricted use of drugs, which is important enough at any time, is all the more important during pregnancy. Difficult births or delay in breathing at birth, with resulting anoxia (lack of oxygen supplied to tlie brain), hemorrhage inside the skull at birth, may also cause intellectual handicap, although a word of warning is needed here. It may be easy enough —and it may be quite wrong —to lay intellectual handicap, later recognised, at the door of a difficult birth or of a poor beginning of breathing at birth, whereas in fact, it may be quite the other way round. Environmental causes after birth include severe head injuries and infections such as encephalitis and meningitis. Genetic Causes

Genetic causes can be established in perhaps 15 to 20 per cent of cases, although with increasing knowledge and better understanding, this figure is likely to rise. In the vast majority of these the parents are completely normal, although latent transmitters of the genetic abnormality. It is likely that many normal men and women are similarly latent transmitters of genetic abnormalities although parents of healthy, normal children. The disease P.K.U., a rare disease characterised by an inborn chemical abnormality, illustrates this point. It is found that once in 20,000 births and yet the gene responsible for it is carried by one in 70 of the general population. There are some 20 to 30 known conditions, all quite rare, transmitted similarly by genes—the genes carried by perfectly normal men and women. Such harmful genes can also arise spontaneously, in a person whose forbears had none of it —a mutation —or from such causes as excessive radiation. Mongols

Mongolism accounts for about one-third of all cases of intellectual handicap but in only perhaps three to five per cent of Mongols is there a true genetic cause. Mongolism is the result of extra chromosomal material in the foetal cells and nearly always this takes the form of an extra chromosome and is a quite unpredictable occurrence, related more closely to the age of the mother than to any other recognised cause at present. Thus, the young pregnant woman, in her early twenties, has perhaps a one in 1500 chance of having a Mongol baby, whereas the older pregnant woman, in her mid-forties, has a one in 50 chance.

In perhaps 3 to 5 per cent of cases of Mongols however, the mother of the child, although apparently quite normal, has a chromosomal abnormality too, with extra chromasomal material in her cells, although the number of her chromosomes is normal. This is not merely a point of academic distinction be-

cause such a mother, whatever her age, has a one in two chance of producing a Mongol child at' each subsequent pregnancy. Moreover, the condition in this mother can be diagnosed by examination of the chromosomal material of her cells. This is a most important development, as it means that the mothers of all Mongol children should have this study done, although 95 per cent or more of them would be quite normal. In New Zealand as yet, there are no easily accessible facilities for this test which is an essential investigation into the cause and potentially a method of prevention of intellectual handicap. Reactions To Presence Reactions to the presence of an intellectuallyhandicapped child vary. With modern values, putting emphasis on the desirability of youth, beauty, self-assurance, bodily perfection, conformity, it is difficult for the outsider to adopt the right attitude to the I.H. child, between the extremes of sentimentality and hostility or indifference. The ideal is that with compassion we come to a clear understanding of the I.H. child’s needs and of his possibilities and help him towards realistic goals of achievement in social relationships, family life, training, work and play. For the parents, the problem is of a different dimension altogether. Some deny the existence of the problem, with false hopes built on false foundations, until time eats them away; some accept with resignation or with feelings of guilt and recriminations, the old quarrels are gone over and the old wives’ tales are trotted out again; some accept with depression; some accept with resentment and aggressiveness, determined to prove the doctor wrong, putting impossible demands upon the child and ultimately creating such tensions that the child does less well than he might otherwise have done. Some overcompensate, even to harming the child by over-protection and neglecting the other children, failing to give them the time and affection that they are entitled to. The real aim should be the acceptance of the diagnosis, the acceptance of the child and adjustment to the realities of the situation. Suitable counselling services can help here, medical, nursing, psychological, but most valuable is the help and experience of mature parents of I.H. children who have faced and come to terms with the same problem themselves. Behaviour Patterns

The behaviour patterns and •thinking of the I.H. child resemble those of the young child in the lack or normal development of logical and consequential thinking, in irresponsibility. Learning processes are slow and depend upon much repetition. Some children are highly distractible, restless, concentrating poorly, over-active. Nevertheless, lack of vitality and drive are commoner than

hyper-excitability, although there is a wide variation between the extremes even at times in the one individual. The general experience of life of the I.H. child is of inadequacy, failure, rejection, and it is not surprising that irritability and aggressiveness mav occur unless it is realised that learning and advance is more difficult for them than for the normal child and that situation needs to be more controlled for them. Nevertheless, given understanding and a suitable environment, most present few behaviour problems. The traditional view as to the capabilities of I.H. children was based on superficial observation but the scientific literature .on intellectual handicap has in recent years emphasised that their capacity has been badly underestimated. For the I.H. adult, with adequate training, incentive and reward, their employment under sheltered conditions is possible and economically sound. One eminent authority in Britain writes: “There is always a great danger of using a low IQ as an excuse for inaction rather than as a startingpoint for planned training and treatment,” and again, “The main distinction between imbecile and normal performance on simple skills is not so much the final level of achievement as the time taken to reach that level.” Opportunity workshops then, are an integral part of any comprehensive programme for the care and training of the intellectually handicapped. The aim of such care and training is that the handicapped, within their capabilities, should be fitted ; for a life of useful work in society, from which comes happiness, contentment, selfconfidence and self-respect and pride, and in the relatives, the lifting of burdens of care, ' doubt and fear, the preserva- : tion of families, the prevention of further anxiety and ’ stress. Such sheltered work- ' shops, within the community, ! are widely accepted in Bri- ' tain and in Scandinavia and ; reach their highest level in 1 Holland. In a limited way but ' with increasing diversity, such . workshops have been functioning under the care of the , I.H.C. Society from Dunedin 1 to Whangarei. : The question may still be 1 asked, although much less fre- ; quently nowadays as to whether any of this is worth- ’ while. A realistic judgment ; would admit that perhaps one ; in every six or seven I.H. ‘ children is so severely affected ; as to be unlikely to benefit , from any scheme of training : and to require only nursing care, warmth, food, cleanliness, clothing, but the great

majority can achieve varying degrees of independence, personally and economically, can experience sorrow and joy, fear and pain and love, pride in achievement, satisfaction from even a simple job well done, and as Pearl Buck says: “The test of any civilisation or any culture is its attitude towards its weakest members. When even the weak have their rights and their opportunities, there is hope for all.”