A research team asked two groups of subjects to sleep in the sleep lab for one night, the first group was arranged to sleep late, thus reducing the total sleep time; the second group was arranged to go to bed early, but was woken up many times in the sleep process  After the second night, the results showed that the positive mood of the second group of testers was seriously affected  Their energy levels are low and positive emotional indexes such as compassion and friendliness have declined  According to this, some researchers believe that being awakened causes the testers not to get enough slow-wave sleep, which is the key to restoring energy
Most of the second batch of testers have not been in a positive mood for a long time
 However, some researchers question the credibility of the study