Read Kanzi: The Ape at the Brink of the Human Mind Online
Authors: Sue Savage-Rumbaugh
One of the characteristics typical of severely mentally retarded individuals is that they tend to be responders, not initiators of communication. As their vocabularies expanded, each of the three subjects began increasingly to initiate communication with their instructors. Ruth was first, after she had learned four lexigrams. Her first spontaneous request was
soda
, to which she then waited for a response. Connie was the second of the three to begin spontaneous use of her lexigrams, after she had learned eleven of them. Bev began after learning twelve lexigrams, but did so much less frequently than Connie and Ruth. When Mary Ann and her colleagues saw the emergence of
spontaneous communication, they decided to respond as parents do with normal children; they treated the utterances as intentional. They therefore adopted a “What you say is what you get” principle. The unfolding of these various communicative skills as the subjects increased their vocabularies was impressive, and it reveals the power of language as its components become assembled.
Another manifestation of the power of language was an unexpected change in the subjects’ social demeanor. They became more sociable and positive and, instead of waiting for things to be done for them, actively took part in their world. They threw fewer temper tantrums and were able to attend to tasks much longer than previously. “They are happier,” observed Rose. “All of this we think is every bit as important as the communication skills. And basically it all can be traced to the word and sentence skills they acquired.”
9
Stephen L. Watson, director of the Developmental Learning Center of Georgia Regional Hospital, said of Bev, Connie, and Ruth’s transformation: “This is not typical of institutionalized people, who are complacent because they grow accustomed to having their needs met before they ask.”
Rose’s remark in attributing Bev, Connie, and Ruth’s increased engagement with their worlds to the power of language seemed plausible, given that
Homo sapiens
is a creature of language whose social fabric is very much the product of words. But her conclusion went beyond instinct, and included a careful study. The study addressed the possibility that the subject’s change in overall social demeanor might have been the result of the novel interaction to which they were exposed during the program, rather than the acquisition of language skills. Rose, Mary Ann, and Adele A. Abrahamsen compared various aspects of Bev, Connie, and Ruth’s behavior with those of individuals who had been exposed to daily contact with instructors but had not been taught to communicate symbolically.
The individuals in the control group did show an increase in their sociability, as Bev, Connie, and Ruth had, but their intentional communication, rate of attentional shift, and attention complexity did not change. Significantly, neither did that of
Max, who was exposed to symbols, but failed to learn. The improvement in Bev, Connie, and Ruth in these three measures can therefore be seen as a direct result of having acquired a degree of symbolic communication. “The acquisition of lexigrams occurred as part of a larger package of developmental changes in this study,” noted Rose and her colleagues, “which is suggestive that the process of acquiring the new symbols is embedded in a causal structure of changes involving several [cognitive] domains.”
10
This study presents a particularly clear insight into the connectedness of cognitive domains, and the power of language in humans in raising general intellectual achievement. I see a similar pattern of transformed behavior in language-trained apes, who appear to be more reflective, attentive, and sensitive to communication with humans. This is strong evidence, I believe, for the evolutionary continuity of the mental substrate between apes and humans.
By the early 1980s, Duane’s vision of a decade earlier had already paid off. He, and later Mary Ann and her colleagues, had made entirely unexpected progress in teaching augmentative communication skills to severely mentally retarded children, by applying theoretical and practical knowledge gained from our ape-language studies. Individuals for whom all traditional methods of speech and other language training had failed, had learned to communicate for the first time in their lives, using Duane’s computer-based keyboard lexigram system. “The results with the Georgia Retardation Center and Developmental Learning Center projects had exceeded all expectations,” Duane now admits. “Quite simply, most people expected that the children would learn nothing at all, but they ended up learning a lot.”
11
Not only had individuals in the program learned productive competence of a vocabulary of lexigrams, but most of them also generalized that competence to labeling and comprehension, and even to spontaneous communication. Most language intervention programs cannot make such claims.
Despite the surprising efficacy of the Sherman and Austin teaching approach, it did conform to what was believed a necessary aspect of language learning in severely mentally retarded individuals: namely, that language skills had to be drilled into place through some kind of structured teaching. True, since the mid-to late 1970s, language intervention practitioners increasingly emphasized a more naturalistic setting for such instruction, but the acquisition of language itself was not naturalistic. Mary Ann and her colleagues worked thoughtfully to produce a naturalistic teaching environment at the Language Research Center, including lexigram games. Nevertheless, they considered themselves active teachers, putting requesting skills in place and watching as other skills emerged.
When, in the spring of 1983, we began to realize that Kanzi had spontaneously acquired a small vocabulary of lexigrams and comprehension of a few spoken words, we were forced to rethink our hypothesis about the acquisition of symbolic communication in apes. Equally, rethinking would be necessary on the “childside.” In a description of the efficacy of the instructional approach with mentally retarded children, Mary Ann and I had said, “These subjects needed to have language learning broken down into small units, just as Sherman and Austin had.”
12
True, these subjects had learned symbolic communication through having language broken down into small units, but perhaps they too could acquire these skills spontaneously, without teaching, as Kanzi had?
“The observations with Kanzi had an immediate effect on our thinking,” recalls Mary Ann. “I was anxious to be able to apply to mentally retarded individuals what Kanzi was telling us, and I was particularly keen to do it with younger children.”
13
Most of the individuals in the Georgia Retardation Center and the Developmental Learning Center studies had been adolescents or young adults. Everything that linguists have learned about language acquisition in mentally normal individuals indicates the importance of early exposure—the existence of a critical period. Those who try to learn a second language after childhood are aware of the struggle it can be, compared with language acquisition in childhood. Mentally retarded individuals
who are trying to learn a communicative system after childhood are therefore doubly disadvantaged, by age and by their cognitive impairment.
In the spring of 1983, a serendipitous event presented an opportunity for beginning to apply a Kanzi-like paradigm in mentally retarded school children. A group of local schoolteachers who were completing a graduate course at Georgia State University paid a visit to the Language Research Center, to observe the program with Bev, Connie, and Ruth. They were enthusiastic about what they saw, and intrigued by the description of Kanzi and his spontaneous acquisition of symbol use and comprehension. They said: “Have you thought about applying some of this out of the laboratory, to children in school, for instance?” There is often a suspicion of experimental programs in schools, not least because researchers all too frequently treat the exercise as a way of collecting data, and don’t have the long-term interests of the schools at heart. Making an approach to engage in some kind of experimental program therefore has to be done with great diplomacy, but it was something Mary Ann and her colleagues planned to do at some point. The invitation by the teachers who visited that day, therefore, was more than welcome. “It was music to our ears,” recalls Rose.
14
Through further discussions with the teachers and their principals, and a scramble to find funds from various sources, a summer program was set up at the Language Research Center for a small number of students from the Clayton County Public School system. The school system benefited because it could offer a summer program for which it otherwise had no funding, and the Language Research Center benefited, because it was taking its first significant step from research in the laboratory to application in schools. The successful summer program revealed that it was possible to make significant progress with children at this severe level of retardation in an unstructured setting that zeroed in on comprehension rather than production.
After this pilot program, Mary Ann wrote a grant proposal that fully incorporated the Kanzi paradigm along with the idea of studying young children in Clayton County schools. As typically happens in such cases, a grant review committee came for a site visit, to see what the Language Research Center offered,
and to hear the arguments in favor of the proposed work. This was in 1984.
“It was early in the morning,” remembers Rose. “We were in the group room, sitting around a table with the review committee. One person on the committee, a very prominent individual in mental retardation research, was saying very kind things about our work, about how innovative it was, and how important for potentially changing the lives of mentally retarded individuals. He was being just
too
kind, and you knew a giant BUT was coming down the pike. Sure enough, at the end he said, ‘But, there is nothing in my experience nor in the mental retardation literature that would indicate such an approach has any chance of working.’ We spent the rest of the day telling him and his colleagues about the success with the chimps, and about the history of how such successes had always translated to mentally retarded individuals.”
15
Rose and Mary Ann must have made a persuasive case, because the grant was awarded.
The new study began in 1985, with thirteen mentally retarded male students having a mean age of twelve years, four months. None of the children had more than ten intelligible spoken words, and all had failed to acquire communicative skills by other teaching methods. Mary Ann’s grant was for a two-year study, which not only would explore the efficacy of truly naturalistic learning but would also compare the effects of school and home environments. For the first year, therefore, half the children were exposed to lexigram use at home, and half at school. During the second year, they used the system both at home and at school.
Mary Ann called the program the System for Acquiring Language (SAL), and it had five components.
The first was the computerized keyboard, which by this time was smaller and more powerful than previous versions, and now included a speech synthesizer. Portability was a crucial factor, because if the system were to be a feasible part of an individual’s
life, it must not be cumbersome and obtrusive. Initially, the children had a Words+ Personal Voice II System, via a Unicorn touch-sensitive expanded keyboard, attached to a Votrax word synthesizer. Later a SuperWolf was substituted for the Personal Voice II. Technology has been central to the language studies from the beginning, first at Yerkes and then at the Language Research Center, and the program has benefited from the microcomputer revolution that has occurred in the past decade. Compared with what is available these days in terms of sophistication and computing power, the SuperWolf is rather primitive. But it is effective, robust, and inexpensive. No doubt great improvements are possible.
The second component was the vocabulary of lexigrams, the assembly of words that were selected in the beginning. Because teachers and parents would be interacting with the children, the written English equivalent was printed on each of the keys, to facilitate two-way communication.