Quantity vs Quality of Sleep and the Timing Relationship Between Sleep States

The quantity and quality of sleep are not equivalent. Sleep disorders can affect the timing and distribution of sleep states, such as REM sleep and deep slow wave sleep. REM sleep is important for learning and emotional processing. In the first half of the night, more time is spent in deep slow wave sleep, while in the second half, more time is spent in REM sleep. Going to bed too late can result in missing out on deep slow wave sleep, while waking up too early can lead to insufficient sleep for memory consolidation and emotional resolution. Our brains have a natural timing for these functions, and if we're not asleep at the right time, we won't get the benefits, even if we adjust our sleep schedule.