Decision-making is guided by memories of option values. However, retrieving items from memory renders them malleable. Here, we show that merely retrieving values from memory and making a choice between options is sufficient both to induce changes to stimulus-reward associations in the hippocampus and to bias future decision-making. After allowing participants to make repeated choices between reward-conditioned stimuli, in the absence of any outcome, we observe that participants prefer stimuli they have previously chosen, and neglect previously unchosen stimuli, over otherwise identical-valued options. Using functional brain imaging, we show that decisions induce changes to hippocampal representations of stimulus-outcome associations. These changes are correlated with future decision biases. Our results indicate that choice-induced preference changes are partially driven by choice-induced modification of memory representations and suggest that merely making a choice - even without experiencing any outcomes - induces associative plasticity.

决策是由期权价值的记忆引导的。然而，从内存中检索项目使它们具有可塑性。在这里，我们表明，仅仅从记忆中检索值并在选项之间做出选择就足以引起海马体中刺激-奖励关联的变化并影响未来的决策。在允许参与者在没有任何结果的情况下在奖励条件刺激之间做出重复选择后，我们观察到参与者更喜欢他们之前选择的刺激，并忽略之前未选择的刺激，而不是其他相同价值的选择。通过功能性脑成像，我们发现决策会导致海马体对刺激-结果关联的表征发生变化。这些变化与未来的决策偏差相关。我们的结果表明，选择引起的偏好变化部分是由选择引起的记忆表征修改所驱动的，并且表明仅仅做出选择——即使没有经历任何结果——也会引发联想可塑性。