Title: Monkey Plays Pac-Man Using Strategy-based Hierarchical Decision-making

Speaker: Dr. Qianli Yang, Postdoctoral fellow, Institute of Neuroscience, CAS

Time: 14:30-16:00, May 31, 2021

Location: Room 1113, Wang Kezhen Building, PKU


People employ strategies to achieve a challenging goal and make the decision making more manageable. Such behavior has only been anecdotally documented in the animals, including nonhuman primates. To quantitatively illustrate strategy-based decision making is not limited to human, we trained two macaque monkeys to play a faithful reproduction of the classic video game Pac-Man with a few monkey-specific adaptations. We further described the monkeys’ decision making with a dynamic hybrid strategy model consisting of six strategies, each of them only considered a specific aspect of the game and used a selected feature set to determine Pac-Man’s movement directions. This model explains the monkeys’ gameplay with over 90% accuracy. It reveals that the monkeys adopted the Take-the-best heuristic by using a single dominating strategy for their decision making at a time. These strategy patterns can be further corroborated by monkeys’ eye movement and pupil dilation patterns. Finally, we demonstrated that the monkeys formed higher level game plans by assembling the basic strategies to handle particular game situations. Our study demonstrated that strategy using is not limited to humans. With the model, the rich but full quantifiable behavior paradigm provides a new approach to study complex animal cognition in the laboratory setting and allows for future investigations that will reveal the neural mechanisms of cognition at a complexity level that has not been achieved.

Host: Dr. Lusha Zhu