Most people dream every night, but many do not remember what happened when they wake up. 

While analyzing dreams over the course of a lifetime can be difficult, researchers seem to agree that several themes frequently pop up as we age. 

For a closer look, KCBS Radio's Bret Burkhart and Patti Reising were joined by Kelly Bulkeley. He's a dream researcher and author of the latest book the Spirituality of Dreaming. He's also the founder of the Sleep and Dream Database.

Image Source / Getty Images