When Effort Invigorates: Instrumental Effort History Increases Cue-Evoked Response Vigour While Preserving Outcome-Specific Transfer

Environmental cues can influence action through outcome-related information learned elsewhere, but whether features of the instrumental acquisition history associated with those outcomes remain behaviourally relevant when the outcomes are later predicted by Pavlovian cues is unknown. Across two experiments, one conducted in the laboratory (N = 54) and one online (N = 67), we separated instrumental acquisition under low- and high-effort response requirements from Pavlovian cue learning. Participants first learned that different actions produced outcomes under relatively low or high effort requirements and separately learned cues predicting those same outcomes. Pavlovian-to-instrumental transfer (PIT) was then tested under extinction, with neither outcomes nor response requirements present. In both experiments, reward-predictive cues elicited greater response vigour than a control cue. Critically, cues predicting outcomes previously obtained under high-effort response requirements elicited greater responding than cues predicting outcomes obtained under low-effort requirements. Specific PIT was robust under both acquisition conditions, with cues selectively promoting actions associated with their predicted outcomes. There was also suggestive evidence that high-effort acquisition amplified the magnitude of specific PIT, but this modulation was not consistently supported across experiments or statistical approaches. No corresponding effect emerged for initial outcome-congruent action selection. Overall, response vigour was modulated by instrumental effort history more consistently than outcome-specific action selection, indicating that features of prior effortful instrumental experience can remain behaviourally relevant when the associated outcomes are later predicted by separately learned Pavlovian cues.