Background: Preserving functional independence in aging populations is a critical global health priority. Habitual behaviours underpin many daily routines supporting independent functioning; however, it is often assumed that aging brings greater reliance on habitual control at the expense of cognitive flexibility, a pattern linked to functional decline and dementia risk. Yet, factors shaping habitual behaviour across aging remain unclear. Understanding how older adults form and execute habits is therefore essential for developing strategies that preserve adaptive functioning across the lifespan.
Method: We examined goal-directed and habitual control in 38 healthy older (Mage=69.03,26F) and 36 younger adults (Mage=23.39,22F) using a novel outcome-revaluation paradigm, the Symmetrical Known-Associations Reversal Task, adapted from the Symmetrical Outcome-Revaluation Task to use semantically associated pairings and two-choice responses rather than Go/NoGo. Participants completed extensive training to form valuable and nonvaluable stimulus-response habits, followed by an outcome-revaluation test phase creating response conflict between habitual and goal-directed control.
Results: During training, both age-groups learned stimulus-response associations, with stronger habit formation for valuable than nonvaluable outcomes, indicating a clear reward asymmetry in habit acquisition. These associations carried forward to the test phase, where they interfered with performance on revalued trials, consistent with habitual responding. Notably, older adults showed comparable habitual interference to younger adults on rewarded trials. Age-related differences were specific to nonvaluable conditions, where older adults continued to demonstrate habitual interference, whereas younger adults’ poorer accuracy suggested nonvaluable stimulus-response habits were never sufficiently formed.
Conclusions: These findings challenge the assumption that aging involves a uniform shift toward habitual control, instead highlighting reward history as a key determinant of habit formation and expression across the lifespan. This has meaningful implications for risk reduction in aging populations, suggesting interventions should target the conditions supporting beneficial habit formation rather than assuming age-related increases in habitual behaviour. The observed value asymmetry highlights habit strength reflects not only repetition, but also how outcomes are experienced, pointing toward approach-oriented programs that leverage positive outcome-associations to build stronger, more durable health-supporting habits. This has direct relevance for designing interventions that support functional independence and promote healthy aging at a population level.