Biology subjects

Aaron M Bornstein

Publications and source records attributed to Aaron M Bornstein.

2 recordsLinked to original sources

bioRxiv2015

What’s past is present: Reminders of past choices bias decisions for reward in humans

We provide evidence that decisions are made by consulting memories for individual past experiences, and that this process can be biased in favor of past choices using incidental reminders. First, in a standard rewarded choice task, we show that a model that estimates value at decision-time using individual samples of past outcomes fits choices and decision-related neural activity better than a canonical incremental learning model. In a second experiment, we bias this sampling process by incidentally reminding participants of individual past decisions. The next decision after a reminder shows a strong influence of the action taken and value received on the reminded trial. These results provide new empirical support for a decision architecture that relies on samples of individual past choice episodes rather than incrementally averaged rewards in evaluating options, and has suggestive implications for the underlying cognitive and neural mechanisms.

Neuroscience↗

bioRxiv2015

Putting value in context: A role for context memory in decisions for reward.

How does experience inform decisions? In episodic sampling, decisions are guided by a few episodic memories of past choices. This process can yield choice patterns similar to model-free Reinforcement Learning (RL); however, samples can vary from trial to trial, causing decisions to vary. Here, we show that context retrieved during episodic sampling can cause choice behavior to deviate sharply from the predictions of RL. Specifically, we show that, when a given memory is sampled, choices (in the present) are influenced by the properties of other decisions made in the same context as the sampled event. This effect is mediated by fMRI measures of context retrieval on each trial, suggesting a mechanism whereby cues trigger retrieval of context, which then triggers retrieval of other decisions from that context. This result establishes a new avenue by which experience can guide choice, and as such has broad implications for the study of decisions.

Neuroscience↗