How well you remember contextual details after learning may depend less on how many hours you slept and more on how continuous that sleep was – and this holds true across age groups, according to new research posted as a preprint on bioRxiv.
A team led by Chuu Nyan and Audrey Duarte at Georgia Tech used actigraphy and electroencephalography (EEG) to track naturalistic sleep in younger and older adults after they encoded object-scene pairs. After a 96-hour sleep-filled delay, participants were tested on both matching and mismatching pairs while event-related potentials (ERPs) were recorded. The goal was to see whether natural variations in post-encoding sleep quality – outside any lab-controlled deprivation or manipulation – predicted how well people remembered contextual information.
Most sleep and memory research has focused on total sleep time or used sleep deprivation protocols. Far fewer studies have examined how naturalistic, uninterrupted sleep relates to memory retrieval and the brain activity that supports it, especially across the adult lifespan where sleep fragmentation becomes more common.
The results showed that greater sleep continuity after encoding predicted better context memory accuracy specifically for mismatching object-scene pairs – the condition that places the highest demand on accurate contextual recollection. This effect was observed across both younger and older adults, suggesting that sleep continuity benefits memory regardless of age.
On the neural side, higher sleep continuity was also associated with larger ERP differences between correct context hits and context misses for matching pairs. These ERP effects mapped onto post-retrieval monitoring processes – the brain activity that occurs after a memory is retrieved, when we evaluate whether the details fit. Again, this pattern held across both age groups.
“What is notable about these findings is that they emerged from naturalistic sleep variation, not from an experimental manipulation,” the researchers note. “Individual differences in how continuous someone’s sleep is after learning appear to matter for both memory behavior and the neural signatures of retrieval monitoring.”
The findings add to a growing body of evidence that sleep fragmentation – even in the absence of total sleep loss – may impair memory consolidation. For older adults, who typically experience more disrupted sleep, this raises the possibility that interventions targeting sleep continuity (rather than sleep duration alone) could support episodic memory in aging.
This is a preprint and has not yet been peer reviewed.
Source: Chuu Nyan, Aiden Wachnin, Soroush Mirjalili, Sahana Ram, Masoud Seraji, Audrey Duarte. “Individual differences in post-encoding sleep continuity predict context memory accuracy and supporting ERPs in younger and older adults.” bioRxiv [Preprint]. 2026 Jul 10. DOI: 10.64898/2026.07.06.736892. PMID: 42465289.