Sleep and Memory: What’s the Connection? August 31, 2026 Sleep and Memory: What’s the Connection? Have you ever struggled to remember something after a poor night’s sleep, only to feel much sharper after getting some proper rest? There’s a good reason for that - Sleep does much more than help us feel refreshed. It gives the brain valuable time to organise, strengthen and store the information we pick up during the day.1 Scientists have studied the connection between sleep and memory for more than a century. We now know that different stages of sleep play important roles in memory consolidation, the process that helps turn new information and experiences into lasting memories.1 How sleep helps memories stick Creating a memory involves more than simply experiencing or learning something. First, information needs to be encoded by the brain. It then needs to be consolidated so it can be stored and recalled later. Sleep appears to provide particularly useful conditions for this second step. During non-rapid eye movement (NREM) sleep, the brain sorts through information gathered during the day. Important memories are strengthened, particularly during deep, slow-wave sleep, and rapid eye movement (REM) sleep also contributes to memory processing. Together, these sleep stages help the brain decide what information is worth holding onto. Sleep also prepares the brain for learning the next day. When you’re well rested, it’s easier to pay attention to new information.2 During sleep, the brain can effectively “replay” memories from the day, strengthening neural connections and helping new information stick. What happens when you don’t get enough sleep? Most of us recognise the foggy feeling that follows a bad night’s sleep. Concentrating can become harder, learning new information may take more effort, and recalling things you already know can feel surprisingly difficult. Sleep deprivation can interfere with the brain’s ability to consolidate new memories.1 It can also affect attention, learning, decision-making and emotional and behavioural control.1 For adults, getting at least seven hours of sleep per night is generally recommended, although individual sleep needs can vary.1 Could a sleep disorder be affecting your memory? Sometimes, persistent problems with memory or concentration may be connected to disrupted sleep. Untreated sleep disorders can make it harder to remember information and complete everyday tasks.1 Obstructive sleep apnea (OSA), for example, repeatedly interrupts breathing and fragments sleep. Common signs include heavy snoring, choking or gasping during sleep and excessive daytime sleepiness. Research suggests OSA can interfere with memory consolidation, making quality sleep important for both feeling rested and supporting healthy brain function.1 If you regularly wake feeling unrefreshed, struggle with daytime sleepiness, have ongoing memory or concentration problems, or have been told that you snore heavily or gasp during sleep, speak with your doctor. Identifying and treating an underlying sleep problem could help you sleep better and give your brain the rest it needs to work at its best. References 1. Pacheco, Danielle, and Anis Rehman. “How Memory and Sleep Are Connected.” Sleep Foundation, 9 May 2024, https://www.sleepfoundation.org/how-sleep-works/memory-and-sleep. Accessed 27 Aug. 2026. 2. Sisson, Jordan. “Sleep’s Crucial Role in Preserving Memory.” Yale School of Medicine, 15 July 2020, https://medicine.yale.edu/news-article/sleeps-crucial-role-in-preserving-memory/. Accessed 27 Aug. 2026.
