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. 2025 Sep 25;19:1649748. doi: 10.3389/fnsys.2025.1649748

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Copyright © 2025 Moneymaker.

This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.

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Diagram of the sleep cycle showing three stages: Light Sleep (1st Stage), Deep Sleep/Dream Sleep (2nd Stage), and Dream Sleep (3rd Stage). Arrows indicate the flow from Initial Sleep through stages, highlighting processes like REM Sleep Assessment, Visual and Non-Visual Memory Evaluation, and Memory Transfer to Long-Term Storage. The center circle focuses on pain/pleasure and emotions. Red arrows outline the cycle’s progression. — The Sleep Cycle image© Vincent B. Moneymaker.