Author Scott Halford says when it comes to the health of your brain, the captain of the ship is sleep. Whether you feel like you have time for it or not, your brain needs you to rest. You severely limit your ability to concentrate and focus when you don’t get enough sleep, and a chronic lack of sleep can even lead to dementia. Sleep is an eraser of stress, and it’s also a consolidator. It allows us to download and consolidate all the thoughts and memories from the day, so we become smarter when we sleep.