Sleep has a great effect on my mood. However, sometimes I have good days when I have had a terrible time sleeping. Researchers have found that lack of sleep removes depression. However, the depression reappears when the person does get some sleep. This connection has been known for many years. However, it is not of much use for it only lasts for a day. But, it does comfort me to know that if I can't sleep, I may be happy the next day--happy, but tired.
Jim S