The first diagnostic category in DSM-IV is mental retardation, which embraces those individuals at the lower end of the intelligence spectrum. Intelligence is defined by psychologists as the ability to solve problems, adapt creatively to changing circumstances, and generally manage one’s affairs successfully and functionally. No definition of intelligence can truly do justice to the complexity of the matter, but various standardized tests exist, and within certain philosophical and practical limitations, they all provide reasonably accurate estimates of an individual’s general intellectual ability, as well as identifying areas of particular strength and weakness.
What’s not generally recognized, however, is that the cutoff point for mental retardation is arbitrarily set at the 2½ % ile mark. In other words, if a person’s measured IQ places him or her within the bottom 2½% of the population, then that person is considered retarded. On the other hand, a person scoring barely above this cutoff is considered to be not retarded. The DSM definition of mental retardation also requires that the individual shows some functional impairment in major life areas, but in practice the diagnosis is driven primarily by the IQ scores, which in the hypothetical cases mentioned above are too close to reliably say that one is more intelligent than the other. Nevertheless the former individual comes out of the testing situation with a diagnosis of mental retardation, the latter does not.
The need for a sharply defined cutoff is driven primarily by bureaucratic concerns. The Social Security Administration, for instance, considers mental retardation a disability, and there is an obvious need for clear answers when people apply for disability benefits. In addition, the federal, state, and many local authorities provide funding for services to people in this category, and there is a need for clear answers as to who qualifies and who does not. Schools receive a great deal of additional funding for each child with mental retardation enrolled in their programs, and formal procedures and cutoffs are clearly needed unless another way of conceptualizing these matters and funding these kinds of services is developed.
When the average citizen is asked about mental retardation, he or she generally conjures up a picture of a child or adult with Down’s syndrome or one of the other physical conditions that causes low intelligence (e.g., microcephaly). What’s not generally appreciated, however, is that about fifty percent of individuals who carry this diagnosis have no detectable physical problem or anomaly. This is a direct result of the arbitrariness of the cutoff point. Other things being equal, intelligence is “spread” or distributed through the population. There will be a small number of geniuses (people with very high IQ’s), most of us will lie somewhere in the middle, and there will be a relatively small number of people who are not very bright. This would be the case even if there were no people with Down’s syndrome or other obvious physical conditions that impact this matter.
By diagnosing mental retardation purely on the basis of IQ and functional limitations, we are lumping together two extremely different groups of people: people with clear neurological deficits and people who simply aren’t very bright. The former have something wrong with their brains, the latter do not. Their brains are fine, they are just not as efficient as those of brighter people, in just the same way, for instance, that one person’s lungs, heart, muscles, etc., might work better than another’s.
The practice of labeling these people as “retarded” has a number of important effects, particularly in the area of diminished expectations. Consider a parent being told, “Your child is not very bright. In fact, in an average group of a hundred children, he would come pretty close to last in intellectual matters. There is nothing wrong with him, as such, it’s just the way he is, in the same way, for instance, that another child might be very short, etc..” Contrast this to, “Your child is retarded,” which is what this parent would be told under the present DSM system of diagnosis, labeling, and categorization. Quite apart from the unpalatability of the message, there is an almost inevitable tendency on the part of the parent to diminish expectations and to assume the child will be incapable of learning various material, much of which is, in fact, well within his or her potential. A great deal has been learned over the past fifty years concerning the negative effects of this kind of stigmatizing labeling, but this body of research is routinely ignored by those who promote and maintain the DSM categorization system.
These kinds of diminished expectations occur also in the classroom. When a teacher has been told that a particular child is retarded, he/she is more likely to accept a lower standard of work from that child than would have been the case had the “retarded” label not been applied.
Another problem with the “diagnosis “ of mental retardation is that it promotes the notion that the problem lies exclusively within the individual – a lack of “intellect.” This kind of thinking goes back to pre-scientific speculation about human activity. Today we know that there is no such thing as intellect. Rather there is behavior which is more or less adaptive – more or less intelligent. And we also know that behavior is always the result of an endlessly dynamic interaction between an individual and his/her environment. The fact is that some home environments are more fostering of intelligent behavior than others, and it is likely that many children currently labeled “mildly retarded” could be helped significantly in this area with some focus of attention on the home environment. The “diagnosis” of “retarded,” however, militates against this kind of intervention, in that the deficiency is presumed to lie within the child rather than in the child’s environment. Because the “diagnosis” appears to be an explanation of the poor performance, it stifles genuine exploration into the true nature of the problem.
Even with regards to the individuals who do have a physical etiology, similar observations apply, and in general mental retardation programs in recent decades have discovered that there is a great deal of untapped potential in their clients, much of which had been obscured in the past by the stigmatizing effects of the label.
Public attitudes towards people of low intelligence have softened markedly in recent decades, probably largely as a result of deinstitutionalization, and the fact that these individuals are routinely obtaining gainful employment in fast food restaurants, grocery stores, and other locations. In many areas despite the DSM label, mental retardation programs have tackled the problems of their clients creatively and energetically, and in many respects have managed to overcome some of the stigma and other negative consequences of the diagnosis.
In the 50’s and 60’s the term “retarded” gradually replaced the earlier technical terms, which were moron, imbecile, and idiot, and at the time represented a clear improvement. “Retardate,” however, has now become a term of disparagement, especially among school children, and the time for terminology update seems overdue.
Because the concept of retardation has been widely accepted in our society, there is a tendency to see it as an explanation for an individual’s low level of functioning. When a teacher, for instance, asks, “Why is Johnny so slow? Why can’t he learn this stuff?” the school psychologist replies, “Because he’s retarded. His IQ is only 65.” Like most mental disorder diagnoses, this looks like an explanation and is generally accepted as such by parents, teachers, and other concerned professionals. Nothing, however, could be further from the truth. The label “retarded” explains nothing. It just means that Johnny scored below a certain cutoff on a test. In other words, he’s not low-functioning because he’s retarded, but rather he’s called retarded because his level of functioning (as measured by this test) is low. This is a very important distinction, because the diagnosis of mental retardation provides the impression that the matter has been explained, and often removes the incentive for any further in-depth investigation or exploration of the individual’s problem. Despite the gains in recent decades, retardation is still widely regarded as an irremediable condition, and the label still carries heavy overtones of hopelessness and diminished expectations.