Brain Imaging Centre, Research Centre for Natural Sciences, Magyar tudósok körútja 2, Budapest, 1117, Hungary.
Department of Cognitive Science, Budapest University of Technology and Economics, Egry József utca 1, Budapest, 1111, Hungary.
Sci Rep. 2021 May 12;11(1):10132. doi: 10.1038/s41598-021-89456-1.
Both primarily and recently encountered information have been shown to influence experience-based risky decision making. The primacy effect predicts that initial experience will influence later choices even if outcome probabilities change and reward is ultimately more or less sparse than primarily experienced. However, it has not been investigated whether extended initial experience would induce a more profound primacy effect upon risky choices than brief experience. Therefore, the present study tested in two experiments whether young adults adjusted their risk-taking behavior in the Balloon Analogue Risk Task after an unsignaled and unexpected change point. The change point separated early "good luck" or "bad luck" trials from subsequent ones. While mostly positive (more reward) or mostly negative (no reward) events characterized the early trials, subsequent trials were unbiased. In Experiment 1, the change point occurred after one-sixth or one-third of the trials (brief vs. extended experience) without intermittence, whereas in Experiment 2, it occurred between separate task phases. In Experiment 1, if negative events characterized the early trials, after the change point, risk-taking behavior increased as compared with the early trials. Conversely, if positive events characterized the early trials, risk-taking behavior decreased after the change point. Although the adjustment of risk-taking behavior occurred due to integrating recent experiences, the impact of initial experience was simultaneously observed. The length of initial experience did not reliably influence the adjustment of behavior. In Experiment 2, participants became more prone to take risks as the task progressed, indicating that the impact of initial experience could be overcome. Altogether, we suggest that initial beliefs about outcome probabilities can be updated by recent experiences to adapt to the continuously changing decision environment.
无论是最初的还是最近获得的信息都被证明会影响基于经验的风险决策。优先效应预测，即使结果概率发生变化，奖励最终比最初经历的更为稀疏或更为丰富，最初的经验也会影响以后的选择。然而，尚未研究扩展的初始经验是否会比短暂的经验对风险选择产生更深远的优先效应。因此，本研究在两项实验中测试了年轻人在气球模拟风险任务中是否会在没有信号和意外变化点的情况下调整其风险行为。变化点将早期的“好运”或“坏运”试验与随后的试验分开。虽然早期的试验大多是积极的（更多的奖励）或消极的（没有奖励），但随后的试验是无偏的。在实验 1 中，变化点出现在前六分之一或三分之一的试验（短暂的经验与扩展的经验）之间，没有间歇，而在实验 2 中，它出现在独立的任务阶段之间。在实验 1 中，如果早期试验的特征是负面事件，那么在变化点之后，与早期试验相比，冒险行为会增加。相反，如果早期试验的特征是积极事件，那么在变化点之后，冒险行为会减少。尽管冒险行为的调整是由于整合了最近的经验，但也同时观察到了初始经验的影响。初始经验的长度并没有可靠地影响行为的调整。在实验 2 中，随着任务的进展，参与者变得更倾向于冒险，这表明初始经验的影响可以被克服。总之，我们认为关于结果概率的初始信念可以通过最近的经验进行更新，以适应不断变化的决策环境。
