IV. FURTHER ELUCIDATION OF LANGUAGE ACQUISITION THROUGH THE STUDY OF DEFECTIVE CHILDREN
The study of the biological basis of behavior in man is severely handicapped by the impossibility of doing crucial experiments that systematically interfere with physiology. Growth of structure, and development. We must, therefore, take resource to pathological deviations。these，of course，are never controlled situations and therefore introduce inaccuracies, but since we have nothing more exact to study ins place, the experimental shortcomings must be taken into account and accepted as inevitable. Simply to ignore or overlook these phenomena is inexcusable as it may result in theories that are flatly contradicted by pertinent facts in pathology.
It is often said that it is difficult enough to understand the development of behavior in the healthy individual and that we should, therefore, not complicate our task by trying to understand at the same time behavioral development in the presence of disease. Such a statement is based on the false assumption that disease result in more complicated behavior. however, we may consider it axiomatic that disease processes do not usually add to the complexity of structure of behavior. Disease may distort or modify some aspects of behavior；or it may block inhibitions or eliminate balancing components of the behavioral structure, throwing development or performance into disequilibrium, such that one component becomes much more prominent than another；or it may eliminate certain superstructures, thus bringing more primitive layers of behavioral into prominence. But disease will not ordinarily produce behavior that goes beyond the level of complexity which is norm. It might often be dangerous to study merely one disease process and then make generalizations based on this one type of pathology. However，if we view a given behavior pattern in the light of a whole spectrum of pathological modifications, we may be able to attain some insight into aspects of that behavior not ordinarily seen.
(1)Language Lacquisition in the Absence Speech Production
Most psychological theories on language acquisition assume that the conditio sine quo non for this development is presence of an appropriate response system(most recently emphasized by Premack and Schwartz,1966)namely random babbling, that，may be shaped into words，phrases and complete and mature utterances。It is a fundamental assumption here that responding is prior，in a sense，to understanding。however，there is a type of childhood abnormality that contradicts this assumption。These are children with an inborn disability to coordinate their muscles of the vocal tract sufficiently to produce intelligible speech。The disturbance is seen in varying degree ranging from mild impediment to congenital anarthria.
I have had an opportunity to study one such case in great detail over a five-year period。This was a child who was nine years old when seen last。He has never been able to babble or，with advancing age，to say anything at all，but there can be no question that he has complete understanding of English。Over the years much material was collected about this case including detailed medical prenatal and postnatal histories，neurological examinations，family and social histories，laboratory and psychological test results(repeated at various intervals),X-rays and electroencephalography，observations during free play in the child’s home and in my office；records were kept during attempts to train him in speech(unsuccessfully),and a report is available on daily private tutoring throughout one summer。This was conducted as a demonstration project to teach this totally inarticulate child the elements of reading。The latter was relatively successful.*The technique used is of considerable interest；the child demonstrated his ability to read by learning to match pictures to words and simple sentences。Absence of articulation should not be automatically regarded as a hindrance to instructing inarticulate children in the three R’s.
The technical details and background for this case are reported in Lenneberg(1962) and a discussion of the etiology of this condition may be found in Lenneberg(1964).
Some details of the patients communication behavior may be worth reporting here.
His crying and laughter had sounded normal since birth。He was able to make other noises，for instance，short，cough-like grunts，accompanying his pantomimed communications。While playing alone，he would readily make noises that sounded somewhat like Swiss yodeling(though he had never had any experience with these sounds) and which do not resemble any kind of vocalization heard among normal American children。When I first saw him，he appeared to have some difficulty in bringing his voicing mechanism under voluntary control。For instance，he was unable to make the pointer of the VU meter in an Ampex tape recorder jump by emitting grunts into a microphone even though he was fully aware of the logical connection between sound and deflection of the pointer and was fascinated by it。he would hold on to microphone and move his head and lips toward it as if to prompt himself for the action；after a few futile attempts and with signs of rising frustration，he would，in desperation，gesture to the examiners mouth，inviting him to make the needle jump, or else simply resort to clapping his hands and accomplish his end this way。With advancing age he learned to control his vocal apparatus to a greater extent。At the time he was last seen he would repeat-with a considerable show of strain-a few words，but the words were barely intelligible and were never produced without support from the speech correctionist or the mother。They had to say the words simultaneously with him.
Some of the spontaneous sounds emitted by the patient at four years were analyzed spectrographically。The spectrograms are grossly abnormal for a child of this age and resemble those of a neonate in a number of respects，such as the unsteadiness in the formant pattern，the intermittent bursts of nonharmonic overtones，and the almost random change in resonance distribution over the spectrum(Lenneberg,1962).The spectrograms may be interpreted either as grossly immature or as evidence of a fixed central nervous system abnormality implicating the basic mechanisms for speech synergism.
From the patients first visit to the clinic it had been obvious that he had a normal and adequate understanding of spoken language。He has been more than twenty times since then，and full comprehension has been confirmed by neurologists，psychologists，speech therapists，medical residents，and teachers。A number of tape recordings have been made of interviews，including a visit to the patients home。Most of the examinations were done without the presence of his mother。At one time，a short series of instructions were tape recorded and transmitted to the patient through earphones。He followed the instructions without being able to see the examiner.
At the age of eight his capacity to comprehend was fully documented in a 16-millimeter sound film which is publicly available.*The film was not rehearsed and the interviewer had been known to patient by sight only。The demonstration includes the following items：ability to chew，swallow，and suck；sounds emitted while playing at age four；tape recordings of mothers-”conversation”-with subject，recorded during a home visit；following commands and answering questions by nodding；a short story is told followed by questions on it which are couched in complex grammatical constructions.
*1：Carried out in cooperation with the Harvard School of Education；special thanks are to Dr.Helen Popp and Dr.Joel Weinberg.
*2：The Acquisition of Language in a Speechless Child。16-millimeter sound film。Running time is 18 minutes，distributed by cinema register，Pennsylvania State University.