| Project/Area Number |
15370033
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| Research Category |
Grant-in-Aid for Scientific Research (B)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Animal physiology/Animal behavior
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| Research Institution | Hokkaido University (2005)
Nagoya University (2003-2004) |
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Principal Investigator |
MATSUSHIMA Toshiya Hokkaido University, Faculty of Science, Associate Professor, 生命農学研究科, 助教授 (40190459)
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| Co-Investigator(Kenkyū-buntansha) |
ヴァロルチガーラ ジョージョ イタリア・トリエステ大学, 心理学部・一般心理学部門, 教授
シラッグ アンドラス ハンガリー, センメルバイス大学・医学部解剖学教室, 教授
カバイ ピーター ハンガリー, 聖イシュトバーン大学・獣医学部生態学科, 教授
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| Project Period (FY) |
2003 – 2005
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| Project Status |
Completed (Fiscal Year 2005)
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| Budget Amount *help |
¥15,200,000 (Direct Cost: ¥15,200,000)
Fiscal Year 2005: ¥3,200,000 (Direct Cost: ¥3,200,000)
Fiscal Year 2004: ¥4,200,000 (Direct Cost: ¥4,200,000)
Fiscal Year 2003: ¥7,800,000 (Direct Cost: ¥7,800,000)
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| Keywords | brain / behavior / emotion / cognition / impulsiveness / memory / striatum / association cortex / 意欲 / 辺縁系 / 鳥 / 基底核 |
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| Research Abstract |
Newly-hatched chicks of precocial birds show choice behaviors based on precise visual discrimination. Taking advantage of these features, we have examined behavioral processes responsible for decision-making, particularly those based on computation of benefit-cost balance. In addition to behavioral experiments and localized brain lesion experiments, we have accomplished a series of neural recording experiments, which lead us to the following conclusions.
1. Basal ganglia (avian homologue of nucleus accumbens) codes proximity of anticipated food reward.
One-to-two weeks old chicks quickly learn to accomplish color-discrimination operant behaviors reinforced by delayed food reward. Localized lesions to the ventral striatum caused a shift toward small-but-immediate (or spatially proximate) reward, away from alternative large-and-delayed (or spatially distant) reward, indicating an enhanced impulsiveness. Choices based on anticipated amount of food remained unchanged. Single-unit recording f
… More
rom this region revealed two populations of neurons, each of which selectively codes either the proximity or the amount, indicating that these two ecological variables are represented in distinct neuronal populations. These results also suggest a strong functional similarity between the avian and mammalian counterparts of the ventral striatum, thus indicating a highly conserved function.
2. Arcopallium (avian anaglogue of association cortex) codes handling cost of anticipated food reward.
Neuronal recordings revealed coding of auditory working memory as well as that of anticipated food reward. Lesions to this area caused a handling-cost aversion without any sign of impulsiveness or the aversion of access time. The arcopallium is a avian-unique structure, which has similar functional roles as the mammalian frontal association cortex. These results suggest convergent evolution of the avian and mammalian telencephalon.
3. Diminishing return and lost opportunity ; laboratory model system of ecologically realistic decision-making.
A novel task has been developed, mimicking the essential features of optimal foraging theory (optimal patch use model) in the laboratory condition using chicks as subject. In particular, the behavioral responses to lost-opportunity have been quantitatively measured, thus allowing us to penetrate into the brain mechanisms underlying the decisions. Less
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