Roger S. Fouts

Acquisition and Testing of Gestural Signs in Four Young Chimpanzees

Two male and two female chimpanzees were each taught ten signs of American Sign Language. The acquisition rates of the signs were compared on the basis of the number of minutes required in training to reach a criterion of five consecutive unprompted correct responses. After the ten signs had been acquired, the chimpanzees were tested in a double-blind procedure for nine of the signs. All four chimpanzees acquired all of the signs. Some signs were consistently easier to acquire than others, and individual differences between the four chimpanzees were found in the acquisition rates and tests.

Acquisition of American sign language by a noncommunicating autistic child.

Experiments in the perception and language abilities of autistic children indicate that the children have auditory-visual association problems. These findings, combined with the findings that autistic communication is primarily gestural, led to the teaching of elements of American Sign Language to a 5-year-old nonverbal autistic boy. Results after 20 hours of training indicate that the child did acquire signs, that increasing signing led to increasing vocal speech, and that the child has rudimentary English syntax. The use of Ameslan signs spontaneously generalized to other situations and the training resulted in increased social interaction.

Language: Origins, definitions and chimpanzees

Abstract Language and its evolutionary origins are examined in the light of empirical data from studies on artificial language acquisition, human language acquisition in the chimpanzee and the definitional problems surrounding language. Rather than providing solutions, questions are raised in regard to the various approaches to the problems of language origin and definitions of language.

Approach and escape to conspecific odors of reward and nonreward in rats

A three-compartment box was used, and a reward odor, or nonreward (extinction) odor, produced by another rat, was present in the middle compartment. Two control odor procedures were also used. The results showed that rats will approach a location in which another rat has previously been given reward more rapidly than they will escape from that location, but showed the opposite effect when the odor was produced by a rat undergoing extinction. The mere presence of an odor associated with another rat had the effect of producing much slower locomotion as compared to a no-odor control condition.

Transfer of signed responses in American Sign Language from vocal English stimuli to physical object stimuli by a chimpanzee (Pan)

Abstract A chimpanzee was taught 10 signs of Ameslan (American Sign Language) using only vocal English words as stimuli. The corresponding physical objects were items found in the subjects home environment, and which he frequently encountered during daily activities. Reference was not made to these items during teaching sessions. Each teaching session was followed by a test session in which the objects were silently presented to the subject and the question What that? was signed to him. The subject acquired all 10 signs in response to the English word stimuli and then successfully transferred these signs to their physical object referents during testing.

Conjugate lateral eye movements in Pan troglodytes.

Abstract The direction of conjugate lateral eye movements was assessed in four juvenile and four adolescent chimpanzees ( Pan troglodytes ). A significant bias in favor of left eye movements was found in the two older adolescents. Neither the two younger adolescents nor the four juveniles revealed a significant asymmetry in the direction of conjugate lateral eye movements. The data suggest that mature members of this species so closely related to man may demonstrate a bias in hemispheric activation similar to that demonstrated by Homo spiens .

Man-Chimpanzee Communication

This chapter traces the scientific inquiries into two-way communication with chimpanzees from the early attempts to establish vocal communication to ongoing research in gestural and symbolic languages. We shall begin by selectively reviewing the historical speculation concerning the possibility of teaching chimpanzees to speak. This will be followed by a review of early experiments in raising chimpanzees in a human home environment, and by a discussion of the more recent experiments concerning the use of gestural languages and symbols in establishing two- way communication.

The maternal behavior of a home-reared, language using chimpanzee

The purpose of this study was (1) to evaluate general maternal behavior and (2) to determine if the presence of a human observer altered the maternal behavior of the home-reared, language using chimpanzee towards an adopted infant. The results showed that the subject,Washoe, was responsive to the behavior of the infant and was an adequate care-giver. However, the style of care-giving behavior was substantially altered by the presence of a human observer.

DISCUSSION PAPER: COMPARISON OF SIGN LANGUAGE PROJECTS AND IMPLICATIONS FOR LANGUAGE ORIGINS

At present there are several different research projects examining language-like behavior in chimpanzees. These studies have been reported in the literature in addition to several more that have been reported by the popular press. Although the projects being performed by established investigators are different from one another in their methodology, it is encouraging to note that in spite of the methodological differences many of the conclusions concerning the capacities of chimpanzees to engage in language-like behavior have been similar. In addition to the similar findings by the different researchers, there have been different findings that may be because of the different methodologies used or particular questions the experimenters were examining. Their differences, however, are complimentary to one another in terms of understanding the chimpanzees’ cognitive capacities. In this paper I shall attempt to point out a few of the differences between two projects using American Sign Language; the project directed by R. Allen Gardner and B. T. Gardner in Nevada, and the sign language project of which 1 am in charge at the Institute of Primate Studies at the University of Oklahoma. First, the Gardners’ project I can be classified as a long-term longitudinal study, examining the development of Sign in chimpanzees. They have been using an immersion technique; i.e., immersing their chimpanzees in an environment of sign language and raising them in much the same fashion as a human child would be raised. At the same time, they were quantifying and recording the sign development by the chimpanzees. In regard to this technique I have heard criticism from individuals who have seen films of the Gardners’ first chimpanzee, Washoe. The criticisms concentrate on the fact that in the films Washoe was constantly being drilled and her environment was full of experimenter-imposed contingencies requiring Washoe to use sign language. This criticism comes from individuals who have not read the many published reports by the Gardnersl or myself3 concerning the project. The purpose of the Gardners films were to record what a chimpanzee looked like when producing signs. I t was not intended to represent a day in Washoe’s life. If it had been, then only a very small percentage of it would have been concerned with drilling, data collecting, and testing. The vast majority of time I spent with Washoe, perhaps over 90% was spent signing to Washoe about such things as breakfast, lunch, tea, dinner, changing diapers, cleaning up potty mistakes, brushing teeth, cleaning the trailer, playing hide and seek, playing go-games, playing in the sand box, and so on. Relative to the signing occurring in the regular routine the time spent in establishing and recording sign reliability data was small indeed. In regard to contingencies imposed on Washoe, these were, in my experience, not unlike those contingencies I place on my own children in regard to language. If my son points to and makes a grunting sound in regard to a glass of milk, even though the meaning of his actions is clear, I require him to ask for it in a correct and polite