It is no great secret that a good night's sleep makes us feel better the next day. We've all had nights where we've tossed and turned, and normally we feel groggy or downright moody come the morning.

Serotonin, dopamine, oxytocin, and endorphins are the famous happy hormones that are responsible for feelings like pleasure, bonding, motivation, and even love. Hormones and neurotransmitters are the ...