Sleep thoughts

Now let's consider the relationship between sleep stages and mental activity.

When people are awakened during slow-wave sleep (Stages 2, 3, or 4), about half the time they report that nothing was happening. In the other 50 to 60% of the cases, they report that they were thinking about something. These thoughts or experiences are called sleep thoughts and usually involve some issue or event that the person had been concerned about during the previous day.

Sleep thoughts are not considered to be genuine dreams because they lack the vivid, action-packed quality of a dream.