Budget Amount *help |
¥50,180,000 (Direct Cost: ¥38,600,000、Indirect Cost: ¥11,580,000)
Fiscal Year 2010: ¥19,500,000 (Direct Cost: ¥15,000,000、Indirect Cost: ¥4,500,000)
Fiscal Year 2009: ¥14,690,000 (Direct Cost: ¥11,300,000、Indirect Cost: ¥3,390,000)
Fiscal Year 2008: ¥15,990,000 (Direct Cost: ¥12,300,000、Indirect Cost: ¥3,690,000)
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Research Abstract |
We examined whether the midbrain dopamine neurons encode signals of long-term reward prediction and its error. Three Japanese monkeys performed multi-step choices for 3 rewards. Anticipatory licking during the task performance showed that monkey's expectation did not reflect reward probability of individual trials but precisely reflected reward value (probability x volume) of expected total rewards with future rewards discounted, value function of reinforcement learning. Remarkably, dopamine neuron activity encoded the long-term reward prediction rather than reward value of individual trials. The results suggested that the dopamine signals of long-term reward prediction may play critical roles in update of value signals for directing future goals in the target structures such as the striatum.
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