D. SEUSS

• One of the systems in the brain that wakes us up is the reticular activating system (RAS) - a part of your brain located just above your spinal column that acts like a gatekeeper or filter for your brain, making sure it doesn’t have to deal with more information than it can handle.

We can remain in stage 4 - similar to a coma or brain death - for only about 30 minutes before the brain wakes up and falls back to sleep again. 

Even healthy sleepers wake several times a night, but might not be aware of it.

Your inner monologue is where you tell yourself, "I don't want to get up yet," or "This is a tasty burger."

Aphasia from Ancient Greek means "without speech." Typically aphasia occurs after a stroke. Reduced blood flow or bleeding causes brain cells to start dying...