Key to learning and forgetting identified in sleeping brain

https://medicalxpress.com/news/2019-10-key-brain.html

Researchers identify three brain waves associated with learning, during sleep - slow, D, and a sleep spindle. The Sleep spindle comes from the thalamus region; that's coming close to the primitive stem brain region.

Regardless, these "brain waves" reminds me of a strobe light. One can make a rotating object look like it's standing still be tuning a strobe light to the right frequency. Seems that something similar is happening in the brain. Brain waves are locking into perceptions and ideas by tuning to a certain frequency.