Rat anterior cingulate cortex continuously signals decision variables in a patch foraging task [article]

Gary A Kane, Morgan H James, Amitai Shenhav, Nathaniel D Daw, Jonathan D Cohen, Gary Aston-Jones
2021 bioRxiv   pre-print
In patch foraging tasks, animals must decide whether to remain with a depleting resource or to leave it in search of a potentially better source of reward. In such tasks, animals consistently follow the general predictions of optimal foraging theory (the Marginal Value Theorem; MVT): to leave a patch when the reward rate in the current patch depletes to the average reward rate across patches. Prior studies implicate an important role for the anterior cingulate cortex (ACC) in foraging decisions
more » ... based on MVT: within single trials, ACC activity increases immediately preceding foraging decisions, and across trials, these dynamics are modulated as the value of staying in the patch depletes to the average reward rate. Here, we test whether these activity patterns reflect dynamic encoding of decision-variables and whether these signals are directly involved in decision-making or serve a more general function such as monitoring task performance or allocating cognitive control. We developed a leaky accumulator model based on the MVT that generates estimates of decision variables within and across trials, and tested model predictions against ACC activity recorded from rats performing a patch foraging task. Model predicted changes in MVT decision variables closely matched rat ACC activity. Next, we pharmacologically inactivated ACC to test the contribution of these signals to decision-making. Despite ACC inactivation, rats still followed the MVT decision rule, suggesting that foraging decision variables represented in the ACC are used for a more general function such as regulating cognitive control or motivation.
doi:10.1101/2021.06.07.447464 fatcat:rhwcxo7gczfhjn77nxs4xpcp6i