Kenji Kobayashi and Ming Hsu
PNAS June 25, 2019 116 (26) 13061-13066; first published June 11, 2019 https://doi.org/10.1073/pnas.1820145116
It is more important than ever to seek information adaptively. While it is optimal to acquire information based solely on its instrumental benefit, humans also often acquire useless information because of psychological motives, such as curiosity and pleasure of anticipation. Here we show that instrumental and noninstrumental motives are multiplexed in subjective value of information (SVOI) signals in human brains. Subjects’ information seeking in an economic decision-making task was captured by a model of SVOI, which reflects not only information’s instrumental benefit but also utility of anticipation it provides. SVOI was represented in traditional value regions, sharing a common code with more basic reward value. This demonstrates that valuation system combines multiple motives to drive information-seeking behavior.
Adaptive information seeking is critical for goal-directed behavior. Growing evidence suggests the importance of intrinsic motives such as curiosity or need for novelty, mediated through dopaminergic valuation systems, in driving information-seeking behavior. However, valuing information for its own sake can be highly suboptimal when agents need to evaluate instrumental benefit of information in a forward-looking manner. Here we show that information-seeking behavior in humans is driven by subjective value that is shaped by both instrumental and noninstrumental motives, and that this subjective value of information (SVOI) shares a common neural code with more basic reward value. Specifically, using a task where subjects could purchase information to reduce uncertainty about outcomes of a monetary lottery, we found information purchase decisions could be captured by a computational model of SVOI incorporating utility of anticipation, a form of noninstrumental motive for information seeking, in addition to instrumental benefits. Neurally, trial-by-trial variation in SVOI was correlated with activity in striatum and ventromedial prefrontal cortex. Furthermore, cross-categorical decoding revealed that, within these regions, SVOI and expected utility of lotteries were represented using a common code. These findings provide support for the common currency hypothesis and shed insight on neurocognitive mechanisms underlying information-seeking behavior.