*Is the Purpose of Sleep to Let Our Brains “Defragment,” Like a Hard Drive?*
….the effect of sleep on for the brain overall may be more like disk
defragmentation, according to this idea.
After heavy use, hard disks tend to get “fragmented.” This is because when
data gets stored, it is written to wherever there happens to be free space
on the disk. This makes it inefficient to keep track of it all as files may
be split and written in many different places. A defrag consolidates the
same data into a more logical order. Defragmentation is a taxing chore for
the computer, so many people schedule it to happen overnight. In the same
way, sleep may serve to reorganize and reconsolidate memories. The
mechanics of how this defragmentation works remain unclear; synaptic
scaling might be just one of several processes at work.
Defragmentation is not an exact analogy, however. The process could also be
likened to archiving your emails to make room in your inbox, or compressing
data into zipped files, to free up room on the disk.