PubMed HealthSearch

Biomedical subjects

P Morrel-Samuels

Publications and source records attributed to P Morrel-Samuels.

2 recordsLinked to original sources

Do conversational hand gestures communicate?

In 5 experiments, male and female undergraduates viewed gestures and tried to select the words that originally accompanied them; read interpretations of gestures' meanings and tried to select the words that originally had accompanied them; tried to recognize gestures they previously had seen, presented either with or without the accompanying speech; and assigned gestures and the accompanying speech to semantic categories. On all 4 tasks, performance was better than chance but markedly inferior to performance when words were used as stimuli. Judgments of a gesture's semantic category were determined principally by the accompanying speech rather than gestural form. It is concluded that although gestures can convey some information, they are not richly informative, and the information they convey is largely redundant with speech.

Adult

Bottlenosed dolphin and human recognition of veridical and degraded video displays of an artificial gestural language.

2 bottlenosed dolphins proficient in interpreting gesture language signs viewed veridical and degraded gestures via TV without explicit training. In Exp. 1, dolphins immediately understood most gestures: Performance was high throughout degradations successively obscuring the head, torso, arms, and fingers, though deficits occurred for gestures degraded to a point-light display (PLD) of the signer's hands. In Exp. 2, humans of varying gestural fluency saw the PLD and veridical gestures from Exp. 1. Again, performance declined in the PLD condition. Though the dolphin recognized gestures as accurately as fluent humans, effects of the gesture's formational properties were not identical for humans and dolphin. Results suggest that the dolphin uses a network of semantic and gestural representations, that bottom-up processing predominates when the dolphin's short-term memory is taxed, and that recognition is affected by variables germane to grammatical category, short-term memory, and visual perception.

Animal Communication