Tomonaga Masaki
Language and Intelligence Section, Primate Research Institute, Kyoto University, Kanrin, Inuyama, Aichi, Japan.
J Comp Psychol. 2007 May;121(2):156-70. doi: 10.1037/0735-7036.121.2.156.
Humans show a reflexive shift in spatial attention triggered by gaze cues. Chimpanzees (Pan troglodytes) have an excellent ability to follow another's gaze, but they exhibit a limited capacity to engage in triadic interactions based on joint attention, suggesting the possibility of contributions of the different mechanisms underlying joint attention between humans and chimpanzees. The present study thus examined how the chimpanzee's visual spatial attention is triggered by gaze cues. Two chimpanzees showed no clear signs of attention shift triggered by various kinds of nonfacial and facial stimuli with averted gaze under the letter-discrimination tasks but showed significant cueing effects when the head-turning cue was presented in a quasi-dynamic manner. These cueing effects were, however, affected by the predictability of the gaze cue: Highly predictive gaze cues caused stronger cueing effects than less predictive cues. Thus, these results suggest that the shift in spatial attention caused by gaze cues does occur in chimpanzees, but, in contrast to humans, vulnerability against the cue predictability suggests that the voluntary mechanism contributes more dominantly than the reflexive mechanism to this attention shift.
人类会因目光线索引发空间注意力的反射性转移。黑猩猩（Pan troglodytes）具有出色的追随他人目光的能力，但它们基于共同注意进行三元互动的能力有限，这表明人类和黑猩猩共同注意背后的不同机制可能存在差异。因此，本研究考察了目光线索如何触发黑猩猩的视觉空间注意力。在字母辨别任务中，两只黑猩猩在面对各种目光回避的非面部和面部刺激时，未表现出明显的注意力转移迹象，但当以准动态方式呈现转头线索时，出现了显著的提示效应。然而，这些提示效应受目光线索可预测性的影响：高度可预测的目光线索比低可预测性的线索产生更强的提示效应。因此，这些结果表明，目光线索引起的空间注意力转移在黑猩猩中确实存在，但与人类不同的是，对线索可预测性的敏感性表明，在这种注意力转移中，自主机制比反射机制发挥了更主要的作用。
