Reward boosts neural coding of task rules to optimize cognitive flexibility

Abstract

Cognitiveflexibilityiscriticalforintelligentbehavior.However,itsexecutioniseffortfulandoften suboptimal.Recentworkindicatesthatflexible behavior can beimproved bythe prospect of reward, which suggeststhat rewards optimizeflexible control processes.Here weinvestigated how different reward prospects influence neural encoding of task rule information to optimize cognitive flexibility. We applied representational similarity analysis to human electroencephalograms, recorded while female and male participants performed a rule-guided decision-making task.Duringthetask,theprospectof reward variedfromtrialtotrial. Participantsmadefaster,more accuratejudgementsonhigh-rewardtrials. Critically, high reward boosted neural coding of the active task rule, and the extent of this increase was associated with improvements in task performance.Additionally,the effectofhigh rewardontask rule codingwasmostpronouncedon switchtrials,where ruleswereupdated relative tothe previoustrial. These results suggestthat reward prospect can promote cognitive performance by strengthening neural coding oftask rule information, helping to improve cognitive flexibility during complex behavior.