| Abstract: | Responses of Atlantic bottle-nosed dolphins (Tursiops truncatus) and of humans were collected and analyzed in order to determine the features required for recognition and discrimination of signs (hand signals) in an artificial gestural communication system. Subjects responded to systematically modified signs in which sign components were contrasted for competitive feature salience. One dolphin, with 6 yrs of training in the language, was shown these modified signs intermixed with normal signs in a linguistic, sentence-comprehension context. A second dolphin, familiar with action signs only and with no sentence-comprehension training, served as a nonlingual control. Human subjects were tested in two parallel tasks. The dolphin with sign-language experience attended to (in order of importance) location, completed temporal pattern, gross motor motion, and direction of motion, as salient features. Fine motor motion, hand shape, and hand orientation were less salient. The non-sign-language dolphin attended to all sign features equally and was unaffected by temporal pattern changes. Humans tested in a linguistic context attended to (in order) gross motor motion, location, and an interaction of fine motor motion, hand shape, and hand orientation. Direction of motion and temporal pattern were not salient. Nonlinguistic-context humans attended to all sign features equally and were unaffected by temporal pattern changes. Results indicate that language experience and/or testing context affect feature salience for sign recognition. (PsycINFO Database Record (c) 2010 APA, all rights reserved) |
