Department of Psychology and Center for Brain Science, Harvard University, 52 Oxford St., room 295.05, Cambridge, MA 02138, USA.
Lawrence Berkeley National Laboratory, Berkeley, CA, USA.
Neuropsychologia. 2018 Nov;120:97-104. doi: 10.1016/j.neuropsychologia.2018.10.009. Epub 2018 Oct 19.
In order to maximize long-term rewards, agents must balance exploitation (choosing the option with the highest payoff) and exploration (gathering information about options that might have higher payoffs). Although the optimal solution to this trade-off is intractable, humans make use of two effective strategies: selectively exploring options with high uncertainty (directed exploration), and increasing the randomness of their choices when they are more uncertain (random exploration). Using a task that independently manipulates these two forms of exploration, we show that single nucleotide polymorphisms related to dopamine are associated with individual differences in exploration strategies. Variation in a gene linked to prefrontal dopamine (COMT) predicted the degree of directed exploration, as well as the overall randomness of responding. Variation in a gene linked to striatal dopamine (DARPP-32) predicted the degree of both directed and random exploration. These findings suggest that dopamine makes multiple contributions to exploration, depending on its afferent target.
为了最大化长期回报，主体必须在开发（选择收益最高的选项）和探索（收集可能有更高收益的选项的信息）之间取得平衡。尽管这种权衡的最优解是难以捉摸的，但人类会使用两种有效的策略：有选择地探索不确定性高的选项（定向探索），以及在不确定时增加选择的随机性（随机探索）。我们使用一个可以独立操纵这两种探索形式的任务，表明与多巴胺相关的单核苷酸多态性与探索策略的个体差异有关。与前额叶多巴胺（COMT）相关的基因的变异预测了定向探索的程度，以及反应的整体随机性。与纹状体多巴胺（DARPP-32）相关的基因的变异预测了定向探索和随机探索的程度。这些发现表明，多巴胺根据其传入靶位对探索做出了多种贡献。
