When and How Does Post-Encoding Wakeful Rest Benefit Memory? A Systematic Review and Meta-Analysis

<p>Engaging in short periods of wakeful rest following encoding can benefit later memory retrieval ofencoded material. The magnitude of and mechanisms driving this wakeful rest effect are, however,unclear. Accordingly, this review's main objectives are 1) estimating an aggregate wakeful resteffect, 2) identifying the main experimental determinants of the wakeful rest effect, and 3)synthesizing insights on the mechanisms driving the wakeful rest effect. For this preregisteredmeta-analysis (PROSPERO registration number CRD42023487595), we searched Google Scholar,PubMed, PsycINFO, PsycART, and Web of Science for all peer-reviewed studies of adult healthyand memory-impaired humans, manipulating participants' post-encoding activities to comparedeclarative memory performance between periods of wakeful rest and other activities. Updatesearches were conducted on 20.05.2026. The identified studies were assessed for potential risk ofbias using the RoB 2 tool and synthesized in a three-level meta-regression approach. In total, weincluded 54 studies with 3673 individual participants contributing data. An aggregate wakeful resteffect of g = 0.35 (95% CI [0.23, 0.46], p &amp;lt; .001) was found, indicating substantially better memoryperformance following post-encoding rest compared to active comparator conditions. Our resultsshow that the magnitude of the wakeful rest effect depends on several, partially intercorrelated,experimental characteristics, including population, comparator condition, and memory measure,and reveal a clear pattern: human declarative memory performance benefits from post-encodingwakeful rest when demands on our memory system are particularly high.</p>