A new study published in Nature has found that pupil dilation during sleep may indicate memories being replayed, while contraction suggests new learning. Researchers used advanced eye-tracking technology and EEG to monitor mice’s brain activity while navigating a maze and sleeping. The data revealed two substages of NREM sleep, one where pupils dilated for past experiences and the other where they contracted for new memories. This finding could provide a solution to the problem of “catastrophic forgetting” in memory consolidation, potentially leading to better memory enhancement techniques and artificial intelligence.
Source: https://www.ndtv.com/science/pupil-size-indicates-which-memories-we-relive-in-dreams-study-7388360