Dr. Jacob M Levenstein

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.    

Background: Habit-based interventions are increasingly used to sustain behaviours supporting healthy aging, yet how older adults form and break habits remains poorly understood. Understanding these processes is critical to designing effective behavior change strategies for aging populations.

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 training to form valuable and nonvaluable stimulus-response (S-R) habits, followed by a test phase creating response conflict to assess habitual interference and goal-directed flexibility.

Results: During training, both age groups learned S-R associations, though these were more robust for valuable trials. At test, habitual interference was comparable for valuable trials across age groups but differed for nonvaluable trials. Older adults showed a behavioral imbalance where habitual responses interfered with goal-directed control, whereas younger adults' poorer accuracy suggested nonvaluable S-R habits were never sufficiently formed.

Conclusions: Rather than reflecting a shift toward habitual control with age, findings suggest behavior across the lifespan is shaped by what is learned and reinforced. This reframes aging as a context of preserved learning potential, where reward history plays a central role in habit formation. These insights provide a more optimistic foundation for designing habit-based interventions that leverage meaningful outcomes to promote adaptive behavior in aging populations.

The ability to sustain attention, thus suppressing or ignoring task-irrelevant stimuli, involves the synchronous firing of neurons in task-relevant networks (1). The EEG power spectrum exhibits a 1/ƒ -like distribution which accounts for aperiodic activity that is thought to be functionally relevant to cognition (2), with recent studies postulating that age-related flattening of the spectrum (decrease in 1/ƒ slope) is linked to declines in cognitive performance (3-5). Here, we examined the association between 1/ƒ activity and sustained attention performance in older adult subjects to illuminate the utility of the spectral slope as a biomarker of attentional decline. 32-channel scalp EEG recordings (sampling rate=1024 Hz) of 86 healthy older adults (50-85 years) were collected in an eyes-closed resting-state condition. We used spectral parameterisation to reveal the aperiodic components (exponent and offset) from the frontal and parietal electrodes, which were selected apriori. Sustained attention was measured using the CANTAB Rapid Visual Information Processing (RVP) task (6). Multiple regression (bootstrapped; 2000 samples, 95% BCa CI) revealed that after controlling for age and gender, frontal aperiodic activity was significantly associated with attentional performance (p = 0.05; R-squared = 0.210). The same association was seen for parietal aperiodic activity (p = 0.03; R-squared = 0.217). These findings indicate that frontal and parietal aperiodic activity may be a biomarker of sustained attention abilities in older adults.