Department of Psychology, Virginia Tech, Blacksburg, VA 24061, USA.
Department of Health Education and Behavior, University of Florida, Gainesville, FL 32611, USA.
Neuroimage. 2017 Nov 15;162:186-198. doi: 10.1016/j.neuroimage.2017.08.071. Epub 2017 Sep 4.
Behavioral studies using delay and social discounting as indices of self-control and altruism, respectively, have revealed functional similarities between farsighted and social decisions. However, neural evidence for this functional link is lacking. Twenty-five young adults completed a delay and social discounting task during fMRI scanning. A spatiotemporal partial least squares analysis revealed that both forms of discounting were well characterized by a pattern of brain activity in areas comprising frontoparietal control, default, and mesolimbic reward networks. Both forms of discounting appear to draw on common neurocognitive mechanisms, regardless of whether choices involve intertemporal or interpersonal outcomes. We also observed neural profiles differentiating between high and low discounters. High discounters were well characterized by increased medial temporal lobe and limbic activity. In contrast, low discount rates were associated with activity in the medial prefrontal cortex and right temporoparietal junction. This pattern may reflect biological mechanisms underlying behavioral heterogeneity in discount rates.
使用延迟和社会折扣作为自我控制和利他主义的指标的行为研究分别揭示了远见和社会决策之间的功能相似性。然而，缺乏这种功能联系的神经证据。二十五名年轻成年人在 fMRI 扫描期间完成了延迟和社会折扣任务。时空偏最小二乘法分析表明，这两种折扣形式都可以很好地用包括额顶叶控制、默认和中脑边缘奖励网络在内的区域的大脑活动模式来描述。无论选择涉及时间或人际结果，这两种形式的折扣似乎都依赖于共同的神经认知机制。我们还观察到区分高折扣者和低折扣者的神经特征。高折扣者的内侧颞叶和边缘活动明显增加。相比之下，低折扣率与内侧前额叶皮质和右颞顶联合区的活动有关。这种模式可能反映了折扣率行为异质性的生物学机制。
