Author(s): KRAFT, V.1, WANNER, P.2, ROIG, M.3, HERMSDÖRFER, J.1, STEIB, S.2, Institution: TECHNICAL UNIVERSITY OF MUNICH, Country: GERMANY, Abstract-ID: 1878

INTRODUCTION:
Whether and how healthy aging affects motor memory formation remains under discussion. Across paradigms, older adults typically start at a lower performance level, yet studies vary considerably in whether they report reduced or preserved motor memory formation in older compared to younger adults [1]. To interpret these inconsistencies, it is important to distinguish encoding motor information during practice from consolidation, i.e., stabilization or strengthening following practice [2]. Heterogeneity across studies likely reflects differences in task type, amount of practice, retention interval, and participant characteristics, or how motor memory formation is operationalized. We therefore aim to synthesize the literature on age-related differences in motor memory formation by quantifying effects on (i) encoding and (ii) consolidation, and by examining potential moderators.
METHODS:
We conducted a systematic literature search in MEDLINE (PubMed), Web of Science, SPORTDiscus, and PsycINFO from database inception to April 2024, reported following PRISMA guidelines. We included peer-reviewed studies that compared healthy older (≥50 years) to younger adults (18-49 years), without additional interventions targeting motor memory formation. Two authors independently screened the retrieved records by examining titles, abstracts, and evaluating the full texts of those not considered out of scope. Additionally, the reference lists of included articles were reviewed. The same authors extracted data to compute effect sizes.
RESULTS:
The comprehensive search yielded 3,629 individual records, of which 344 are eligible for qualitative synthesis after screening. Of these, 180 experiments investigated consolidation measures in addition to encoding. The qualitative analysis revealed substantial heterogeneity across studies, with younger adults more likely to outperform older adults in encoding or consolidation measures. The overall ambiguity emphasizes the variety of study designs and the need for further analysis. Thus, a quantitative synthesis is currently being prepared to estimate pooled effects and potentially explain variability via moderators.
CONCLUSION:
This review will help to clarify whether aging differentially affects motor memory encoding and consolidation, and under which conditions (e.g., task type, retention interval) age-related differences are most pronounced. Beyond helping to explain some of the observed variability, our findings may support tailored recommendations to enhance motor memory formation across various contexts for older adults.

References
[1] Voelcker-Rehage, C. (2008). Motor-skill learning in older adults-a review of studies on age-related differences. European Review of Aging and Physical Activity, 5(1), 5–16.
[2] Krakauer, J. W., Hadjiosif, A. M., Xu, J., Wong, A. L., & Haith, A. M. (2019). Motor learning. Comprehensive Physiology, 9(2), 613–663.