Primatology Centre of Strasbourg University, Fort Foch, 67207, Niederhausbergen, France.
Anim Cogn. 2013 Mar;16(2):155-63. doi: 10.1007/s10071-012-0558-y. Epub 2012 Sep 6.
A pointing gesture creates a referential triangle that incorporates distant objects into the relationship between the signaller and the gesture's recipient. Pointing was long assumed to be specific to our species. However, recent reports have shown that pointing emerges spontaneously in captive chimpanzees and can be learned by monkeys. Studies have demonstrated that both human children and great apes use manual gestures (e.g. pointing), and visual and vocal signals, to communicate intentionally about out-of-reach objects. Our study looked at how monkeys understand and use their learned pointing behaviour, asking whether it is a conditioned, reinforcement-dependent response or whether monkeys understand it to be a mechanism for manipulating the attention of a partner (e.g. a human). We tested nine baboons that had been trained to exhibit pointing, using operant conditioning. More specifically, we investigated their ability to communicate intentionally about the location of an unreachable food reward in three contexts that differed according to the human partner's attentional state. In each context, we quantified the frequency of communicative behaviour (auditory and visual signals), including gestures and gaze alternations between the distal food and the human partner. We found that the baboons were able to modulate their manual and visual communicative signals as a function of the experimenter's attentional state. These findings indicate that monkeys can intentionally produce pointing gestures and understand that a human recipient must be looking at the pointing gesture for them to perform their attention-directing actions. The referential and intentional nature of baboons' communicative signalling is discussed.
指向手势创建了一个参照三角形，将远处的物体纳入信号发送者和手势接收者之间的关系中。指向手势长期以来被认为是人类所特有的。然而，最近的报告表明，圈养的黑猩猩会自发地做出指向动作，猴子也可以学习这种行为。研究表明，人类儿童和大型猿类都会使用手动手势（例如指向）、视觉和声音信号，有意地传达对无法触及的物体的信息。我们的研究着眼于猴子如何理解和使用它们习得的指向行为，探讨这是一种条件反射、依赖强化的反应，还是猴子理解为一种操纵伙伴注意力的机制（例如人类）。我们使用操作性条件反射对 9 只受过训练表现出指向行为的狒狒进行了测试。更具体地说，我们研究了它们在三种不同的人类伙伴注意力状态下，有意传达无法触及的食物奖励位置的能力。在每种情况下，我们都量化了沟通行为（听觉和视觉信号）的频率，包括手势和远处食物与人类伙伴之间的目光交替。我们发现，狒狒可以根据实验者的注意力状态来调节它们的手动和视觉沟通信号。这些发现表明，猴子可以有意地做出指向手势，并理解人类接收者必须看着指向手势，它们才能执行注意力引导动作。我们讨论了狒狒沟通信号的参照性和意向性。
