2026-04-21 京都大学
結果の概要：ニホンザルは「ほどよく不確実」な刺激を探索する傾向を示した。作成：壹岐朔巳（一部GPT-5.4を使用）
＜関連情報＞
- https://www.kyoto-u.ac.jp/ja/research-news/2026-04-21-0
- https://www.kyoto-u.ac.jp/sites/default/files/2026-04/web_2604_Iki-e1e5a66963717beb484f330f8d2a5e65.pdf
- https://www.cell.com/iscience/fulltext/S2589-0042(26)01195-8
- https://www.cell.com/iscience/pdf/S2589-0042(26)01195-8.pdf
マカクザルにおける中程度の不確実性を伴う事象の本質的な再現 Intrinsic recreation of moderately uncertain events in macaques
Sakumi Iki ∙ Haruhiko Iwaoki ∙ Yuko Hattori ∙ Ikuma Adachi
iScience Published:April 18, 2026
DOI:https://doi.org/10.1016/j.isci.2026.115820
Highlights
- A reward-free touchscreen game was developed for Japanese macaques.
- Two buttons triggered puppet appearances with different noise levels.
- Choice bias shifted toward selecting the intermediate-noise button.
- The intermediate-noise button was reselected more quickly.
Summary
Curiosity drives information-seeking without extrinsic incentives. Prior studies using looking-time measures suggest that curiosity peaks at intermediate uncertainty. Yet developmental and comparative research often reports that increased looking does not necessarily translate into action, leaving open whether animals intrinsically take overt actions generating intermediate uncertainty. Here, we show that monkeys are biased not only to look longer, but also to spontaneously interact with their environment in ways that recreate intermediate uncertainty. In a reward-free, hide-and-seek-like touchscreen game, Japanese macaques (Macaca fuscata) chose between two buttons that produced puppet appearances with different levels of spatial noise: intermediate vs. low (Experiment 1) and vs. high (Experiment 2). When noise variation was perceptible rather than imperceptible, macaques shifted their choice bias toward the intermediate-noise button by 9.6% (Experiment 1) and 13.5% (Experiment 2), and reselected it faster. Such intrinsic tendencies may optimize information gain by promoting engagement with stimuli offering maximal learning opportunities.
