When the sleepy participants’ eyes closed in “microsleep,” a.k.a. dozing, the researchers saw reduced activity in the thalamus, the part of the brain responsible for relaying sensory and motor signals to other parts of the brain. The thalamus is also responsible for regulating sleep (and the same effect was found in the scans of rested participants) so this part isn’t very surprising.
But more surprisingly, the researchers saw increased activity in the parts of the brain associated with sensory processing, which could account for the vivid images that seem to spring up when you first drop off to sleep. The researchers also observed more activity in the frontal parietal lobe, responsible for helping you pay attention, likely as a result of the brain’s attempt (and failure) to obey the “stay awake” command.
Like most people, my brain starts to fizzle out between 2 and 3pm. According to science, this isn’t due to a lunch hangover but rather a part of our circadian rhythm.
To preempt the inevitable afternoon slothfulness, author Dan Pink proposes to take a nappuccino. He recommends that before you take your 20-minute nap (science shows that more than 20 minutes can make you feel drowsier), you should drink a cup of coffee.
The caffeine won’t fully engage in your bloodstream for about 25 minutes, so drink up right before you lie down.
The pre-nap caffeination will give you an extra boost when you wake up. Your brain will be sharper and more focused. You’ll also receive all the benefits of a nap: lower blood pressure and a stronger heart.
You can read more about the nappuccino productivity hack here.