两个维度的价值:多巴胺神经元代表但不是aversiveness奖励

作出决定,我们需要估计的感官刺激和运动行为的价值,他们的“善良”和“坏处”。We can imagine that good and bad are two ends of a single continuum, or dimension, of value. This would be analogous to the single dimension of light intensity, which ranges from dark on one end to bright light on the other, with many shades of gray in between. Past models of behavior and learning have been based on a single continuum of value, and it has been proposed that a particular group of neurons (brain cells) that use dopamine as a neurotransmitter (chemical messenger) represent the single dimension of value, signaling both good and bad.

这里的实验报告表明多巴胺神经元奖励的价值而不是惩罚很敏感(如苦味的aversiveness)。这表明奖励和aversiveness表示为两个离散维度(或类别)。“奖励”是指美好的事物的类别(食物、水、性、金钱等等),和“惩罚”类别的坏事(刺激与对身体的伤害,引起疼痛或其他不愉快的感受或情绪)。

而不是让一个神经递质(多巴胺)代表的是单一维度的价值,目前的结果意味着四神经递质来表示两个维度的存在价值。多巴胺信号依据奖励(“收益”)和其他一些神经递质可能信号证据奖励(“损失”)。同样的,应该有一个神经递质危险的证据,另一个用于安全的证据。有趣的是,有三个类似的其他神经递质多巴胺在许多方面(5 -羟色胺、去甲肾上腺素和乙酰胆碱),它是可能的,他们可以代表其他三个值的信号。