Knutson B, Adams C M, Fong G W, Hommer D
National Institute on Alcohol Abuse and Alcoholism, National Institutes of Health, Bethesda, Maryland 20892-1610, USA.
J Neurosci. 2001 Aug 15;21(16):RC159. doi: 10.1523/JNEUROSCI.21-16-j0002.2001.
Comparative studies have implicated the nucleus accumbens (NAcc) in the anticipation of incentives, but the relative responsiveness of this neural substrate during anticipation of rewards versus punishments remains unclear. Using event-related functional magnetic resonance imaging, we investigated whether the anticipation of increasing monetary rewards and punishments would increase NAcc blood oxygen level-dependent contrast (hereafter, "activation") in eight healthy volunteers. Whereas anticipation of increasing rewards elicited both increasing self-reported happiness and NAcc activation, anticipation of increasing punishment elicited neither. However, anticipation of both rewards and punishments activated a different striatal region (the medial caudate). At the highest reward level ($5.00), NAcc activation was correlated with individual differences in self-reported happiness elicited by the reward cues. These findings suggest that whereas other striatal areas may code for expected incentive magnitude, a region in the NAcc codes for expected positive incentive value.
比较研究表明伏隔核（NAcc）与奖励预期有关，但在奖励与惩罚预期过程中该神经基质的相对反应性仍不明确。我们利用事件相关功能磁共振成像，研究了递增货币奖励和惩罚预期是否会增加8名健康志愿者伏隔核血氧水平依赖对比（以下简称“激活”）。递增奖励预期既引发了自我报告幸福感增加，也引起了伏隔核激活，而递增惩罚预期则两者均未引发。然而，奖励和惩罚预期均激活了不同的纹状体区域（内侧尾状核）。在最高奖励水平（5.00美元）时，伏隔核激活与奖励线索引发的自我报告幸福感的个体差异相关。这些发现表明，虽然其他纹状体区域可能编码预期奖励大小，但伏隔核中的一个区域编码预期正奖励价值。
