Recent research suggests that reinforcement learning may underlie trait formation in social interactions with faces (Hackel, Doll, & Amodio, 2015; Hackel, Mende-Siedlecki, & Amodio, 2020). The current study investigated whether the same learning mechanisms could be engaged for trait learning from voices. On each trial of a training phase, participants (N = 192) chose from pairs of human or slot machine targets that varied in the 1) reward value and 2) generosity of their payouts. Targets were either auditory (voices or tones; Experiment 1) or visual (faces or icons; Experiment 2), and were presented sequentially before payout feedback. A test phase measured participant choice behaviour, and a post-test recorded their target preference ratings. For auditory targets, we found no effect of reward or generosity on target choices, but saw higher preference ratings for generous humans and slot machines. For visual targets, participants learned about both generosity and reward, but generosity was prioritised in the human condition. These findings demonstrate that (1) reinforcement learning of trait information with visual stimuli remains intact even when sequential presentation introduces a delay in feedback and (2) learning about traits and reward in such paradigms is weakened when auditory stimuli are used.

最近的研究表明，强化学习可能是人脸社交互动中特征形成的基础（Hackel、Doll 和 Amodio，2015 年；Hackel、Mende-Siedlecki 和 Amodio，2020 年）。目前的研究调查了相同的学习机制是否可以用于从声音中学习特征。在训练阶段的每次试验中，参与者 (N = 192) 从成对的人类或老虎机目标中进行选择，这些目标在 1) 奖励价值和 2) 慷慨的支出方面有所不同。目标是听觉（声音或音调；实验 1）或视觉（面部或图标；实验 2），并在支付反馈之前按顺序呈现。测试阶段测量参与者的选择行为，后测试记录他们的目标偏好评级。对于听觉目标，我们发现奖励或慷慨对目标选择没有影响，但看到对慷慨的人和老虎机的偏好评级更高。对于视觉目标，参与者了解了慷慨和奖励，但在人类条件下，慷慨是优先考虑的。这些发现表明，（1）即使顺序呈现引入反馈延迟，特征信息与视觉刺激的强化学习仍然完好无损；（2）当使用听觉刺激时，对此类范式中特征和奖励的学习会减弱。