Theories of Sleep: The Role of Slow-Wave Sleep in Memory Consolidation

Introduction Sleep is defined as a loss of unconsciousness, a reversible natural state with reduced responsiveness to external stimuli and relative inactivity 1. Due to the high selection pressure, this inactivation evolved among species. This indicates that sleep plays an important role. Multiple studies have shown that sleep enhances declarative and procedural memory 2, 3. Therefore, memory enhancement is one of the surface functions of sleep.

Note: The dual process theory suggests that certain memory depends on certain sleep states such as REM sleep or slow wave sleep (NREM sleep stage). In sequential processing theory, we think that an orderly sleep stage is necessary for memory. For example, slow wave sleep, then REM sleep. 20 These two theories help to explain how the student's sleep patterns affect learning 21. 22 REM sleep usually occurs every 90-120 minutes, but it is usually done 4-5 times every night. College students in the morning will not be able to reach the last 1-2 REM sleep period and the program memory can be adversely affected because REM sleep period gradually becomes longer and the last episode is approaching the rise .

Several stages of sleep, including depth, slow wave sleep and REM sleep are important for memory consolidation. New research provides more evidence that the multiple stages of non-REM sleep when the brain produces electrical activity called the sleeping axis also are important for preserving memory and later remembering them . Prefrontal cortex - an area of ​​the brain that deals with planning and complex decision-making. You can call for complicated and thorough judgment and you can balance risks and rewards. Especially serious blows due to sleep deprivation. Sleep deprivation, when making decisions is impulsive. Impulsive decisions tend to favor immediate rewards. According to the survey, you are likely to take dangerous actions.

Mander said another trend in the scientific literature on sleep involves strengthening memory. In the past, the role of sleep was thought to be to protect the brain from interference stimuli, thereby strengthening the memory that was predominantly coded during the day. However, in the new study it is suggested that sleep is far from the passive process and sleep is best explained as an active brain condition that optimizes memory consolidation. It consolidates memory by triggering the same set of neurons that are triggered when memory is first formed and this combination occurs during slow wave sleep (Phase 3 and Phase 4).