A recent scientific study (made on fruit flies) has shown that sleep actually kills some synaptic connections in the brain:
“There are a number of reasons why the brain can’t indefinitely add synapses – including the finite spatial constraints of the skull. We were able to track the creation of new synapses in fruit flies during learning experiences – and to show that sleep pushed that number back down”
This makes an awful loot of sense. Upon birth, it has been proven that babies have the synaptic potential to adapt to any kind of environment. During growth, the synaptic/neuronal system adapts to its environment by nurturing the cells that are often called up, and letting the unwanted cells starve to death. Killing unwanted synapses is a way to polish our nervous system to make us more fit to survive in the environment we live in. In other words, refining our nervous sytem makes us smarter.
The study mentioned above shows that this refinement happens during sleeping hours. More interesting in this study is the previous finding from the same research group that fruit flies were getting more sleep when they had richer social interactions:
Shaw’s lab had previously determined that fruit flies sleep longer following social interactions, rather like a human who has been through a busy day.
In other words, interacting with others boosts your synaptic activity, which in turn makes you tired, to finally doze off and kill all that unnecessary nervous mass that slurps your precious proteins. So poke around and write on walls and make new friends: Your brain cells will love you for it!