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Morantin, M.

Publications and source records attributed to Morantin, M..

2 recordsLinked to original sources

Aging effects on retrospective and naturalistic encoding of time and their relationship with memory.

In everyday life, attention is not explicitly directed toward time. Yet, we can reconstruct how long an experience lasted from the memory traces it left behind, a process intertwined with episodic memory and subjective experience. As both memory and temporal processing change with advancing age, investigating aging effects could provide critical insights on these reconstructive processes. In this study, 31 younger (aged 24{+/-}3) and 36 older (aged 69{+/-}6) healthy adults completed two EEG sessions: 1) a resting-state recording followed by an unexpected retrospective time estimation, and 2) a video-based prospective duration estimation task where participants encoded and judged the duration of 50 naturalistic videos (2-32s) varying in eventfulness. Using a cycle-by-cycle burst analysis of alpha (: 8-12 Hz), we examined oscillatory correlates of both retrospective temporal judgement and prospective temporal processing. Behaviorally, both groups reconstructed short intervals similarly, but older adults produced longer prospective duration estimates than younger adults for longer video clips (16-32s), particularly under low-eventfulness. Regression analyses also showed that individual differences in older adults' prospective duration judgments were influenced by both their retrospective time estimation and episodic memory abilities, especially for longer videos. At the neural level, resting-state -burst dynamics were higher in older adults and predicted, with -power, longer retrospective estimates in older adults. Additionally, resting-state -burst activity predicted -burst during video encoding in both groups. Together, these findings reveal that individual -power and -burst dynamics could constitute memory-based time-tracking mechanism that aging reshapes in ways that manifest behaviorally under naturalistic conditions.

neuroscience↗

How aging reshapes implicit learning: behavioral and oscillatory evidence from an EEG-adapted Fast Mapping paradigm.

Most of everyday memory formation occurs without deliberate intent, yet the neural mechanisms supporting implicit encoding and their reorganization with age remain poorly understood. The present study investigated age-related changes in implicit learning using an EEG-adapted Fast Mapping paradigm (the Disjunctive Inference Implicit Learning Test, DIILT) in 31 younger and 35 older adults, paired with a comprehensive neuropsychological assessment and a one-month delayed recognition measure. Behaviorally, younger adults rapidly acquired novel implicit associations across the learning phase, whereas older adults showed persistent reliance on familiar items and limited improvement for novel associations. Critically, both groups successfully retained novel associations after one month, with implicitly learned associations showing greater long-term stability than explicitly encoded ones regardless of age. At the neural level, younger adults exhibited early posterior theta engagement for novel compared to familiar items, which disappeared by the end of learning, consistent with novelty-driven associative encoding. Older adults showed no such theta modulation for novel items, pointing to reorganization of the neural mechanisms supporting implicit encoding. Theta dynamics predicted immediate recognition in younger adults but not in older adults who rather showed theta association with processing speed, suggesting an age-related shift from memory-specific binding to domain-general cognitive resource allocation, consistent with neural maintenance frameworks of cognitive aging. These findings demonstrate that implicit encoding produces durable memory traces across the lifespan but relies on reorganized oscillatory dynamics in aging, with implications for understanding how cognitive aging reshapes everyday memory formation.

neuroscience↗