Language and non-humans

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TALKING WITH THE HANDS

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American Sign Language (ASL), the manual-visual language used by deaf people in the United States, is a full-fledged linguistic system in which the hands and arms communicate by means of location of hands, hand shape, movement and the orientation of the palm. There are about twenty-five locations, forty five ways of shaping the hand, ten distinct movements and ten ways of orienting the palm. The signs of ASL may or may not have an exact English equivalent, but anything said in one language can be translated into the other. Speakers of ASL sometimes supplement their “speech” by finger spelling words, but finger spelling is used primarily for proper names, for borrowed words from English, or to “talk” with someone who is not fluent in ASL.

Signers can refer to other times and other places, and they can combine individual signs into an unlimited number of statements. At one time, linguists assumed that ASL was an incomplete language that lacked function words, but as more linguists fluent in the language, it became clear that function words and syntax are present, although not based on any English equivalent. One example is raised eyebrows to indicate a subordinate clause. Another example is the location of the hand in relation to the face to indicate gender: the sign for “girl” is produced with the hand touching the cheek; the similar sign for “boy” is produced at the forehead. Other markers can change a sign from a verb to a noun, note whether an action is a single or a habitual occurrence, indicate plural, signify past or future, make clear that the sign is being used in a metaphorical sense, or indicate that the signer is coining a new term.

At the university of Hawaii, several female bottle nosed dolphins have shown that they “understand” a variety of sentences conveyed through one of two languages. One is a visual language consisting of hand and arm signals, and the other is an acoustic language consisting of whistle like sounds. The dolphins first learned a small set of signals for simple actions, which the trainers taught them using shaping techniques with reinforcements of fish and the trainer’s approval. As they learned the set of actions, the dolphins also learned signs for categories of objects, such as balls, hoops, pipes and baskets. The objects in each category varied from day to day in color, size and exact shape, so the dolphins were learning to recognize a variety of instances for each concept. The dolphins also learned modifiers as well as to reply “yes” or “no” by pressing the appropriate pane.

All commands were constructed from a simple phrase-structure grammar, which could be used to generate sentences up to five “words” long. These five-word sentences made possible a very large number of combinations of signs, so the researchers were able to train the dolphins on a subset of sentences and to test the dolphins’ understanding of sentences to which they had never been exposed. The dolphins showed evidence of an ability to respond correctly to novel sentences. For example, after a dolphin learned “Hoop fetch surfboard” (which told the dolphin to swim to the hoop and take it to the surfboard), it was able to understand “Hoop on surfboard” (which told it to get the hoop and put it on the surfboard). They usually carried out such actions quickly and without error, despite the presence of distraction objects and other dolphins moving about in the tank. Such findings demonstrate a grasp of syntax.

Clearly, attempts to teach language to non-humans, have produced some impressive results, revealing glimmers of the central characteristics of human language: expressiveness, productivity and displacement.

Дата добавления: 2014-12-27