Publishing study results, videos and information about Kumamoto Sanctuary.
When we watch a movie, we anticipate what will happen next, get excited about ongoing events, and learn from what we saw in the movie. This is because we spontaneously use our advanced cognitive and emotional skills when we watch movies. Do nonhuman animals do the same as we do? Using state-of-the-art sensor technologies such as eye-tracking and thermo-imaging, I found that they indeed do as we do. Based on their understandings about the story plots in movies, they anticipatorily look at, and emotionally respond to, the actions and events described in movies.
To what extent are the cognitive abilities of nonhuman animals similar to ours and how are they different from ours? I have challenged this question using state-of-the-art sensor technologies such as an eye tracker.
I did my PhD (supervised by Dr. Masaki Tomonaga) at Primate Research Institute, Inuyama, Japan. There, I have started the eye-tracking projects with great apes. Since then, I’ve been fascinated by what is revealed by their eye movements; perception, cognition, and emotion. I did my post-doc (supervised by Dr. Josep Call) at Max-Planck Institute for Evolutionary Anthropology, Germany. There, I met my recent interests; how apes anticipatorily look at the other individuals’ actions and the impending events in movie stories. At present, I’m working at the Kumamoto Sanctuary of Kyoto University, located in Kumamoto, Japan, where we have 50+ chimpanzees and 6 bonobos. This is one of a few research institutes in the world that owe a large number of great apes. Here, I’m continuing the same line of research as well as developing new research paradigms such as thermo-imaging.
In our recent experiment, we made a movie (directed by ourselves) in which an aggressive ape-like character jumped out from one of the two tunnels. Bonobos and chimpanzees watched this movie only once on the first day. Twenty-four hours later, they watched the same movie again. We used an eye-tracker to record their spontaneous eye movements while they were watching the movie. We found that, on the second day, they anticipatorily look at the same tunnel before the ape-like character jumped out. This indicates that the great apes spontaneously remember what they have seen at least over a day, an ability which is similar to episodic memory in humans. Right now, using a similar paradigm using story movies, we are investigating whether great apes anticipate the actions of a movie character based on their understandings about the character’s “intentions”; in a so-called “false-belief” task. Previous research have shown that great apes understand the intention of other individuals. However, one remaining question is whether they can predict the other individual’s actions even when this individual has a false belief. I’m very excited about the coming results, and what can be revealed by our novel research paradigm in future.
In our recent experiment, we presented to bonobos and chimpanzees various snapshot pictures depicting faces and bodies of conspecifics and compared between the species their spontaneous eye movements while they were observing those pictures. What we have discovered was quite striking. Bonobos and chimpanzees showed species-specific eye movement patterns. An analysis revealed that a randomly-chosen individual from the tested population can be correctly identified for her/his species over 80% accuracy (that is, either a bonobo or a chimpanzee) only from her/his eye movement patterns. Of particular interest was that bonobos viewed the depicted eyes in the pictures significantly longer than did chimpanzees. It is interesting to observe such large differences among very closely-related species, and this suggests that such differences are likely to have evolved in a short period of phylogenetic time. I believe that discovering more of such differences between bonobos and chimpanzees would shed light on the evolution of human mind as we ourselves have evolved from the common ancestor of bonobos and chimpanzees.
Currently, I’m planning to expand my research interests to a wider variety of animal species, including non-primates. I’m doing a collaborative work with researchers at Oxford University to investigate how a flock of birds use their vision to coordinate their group flights. I believe that, as we learned so many things from the eye movements of great apes, we will discover many exciting facts in this new study.