As someone who sleeps very heavily, I rarely remember my dreams from the previous night. I go to sleep, I black out, I wake up hours later. But for many people, dreams play a huge role in their sleeping habits. And for a lucky few, there occurs the sensation of sharing their dreams with another person - while they're happening. What does it mean if you and your friend have the same dream? Your mutual dreaming may indicate the intense depth of your relationship.
Very little scientific study has been dedicated to "mutual dreaming," for several reasons. First, it's fairly rare. The majority of evidence indicating even the existence of mutual dreaming is anecdotal. Second, it's a phenomenon that's nearly impossible to predict or track. Even if you do end up mutually dreaming with someone, how would you know ahead of time which person in your life that would be? Third, there remains skepticism among scientific communities that the phenomenon even happens at all. Folks often only find out they've shared a dream when mentioning it off-handedly. It's incredibly difficult to quantify or regulate, and then, of course, there's the "power of suggestion." Human minds are wild, huh?
And finally, there's no one, singular consensus as to why humans dream at all. What purpose does it serve? What greater point is dreaming indicative of? Nevertheless, friends, parents and their children, therapists and clients, lovers, twins - all kinds of folks in all kinds of relationships have reported experiencing the same dream at the same time. What does it mean? Let's first go into some REM cycle basics. A little Dreaming 101.
One of the more widely accepted theories regarding what we dream and why posits the phenomenon as our brains working through all the mountains of stuff, of data, basically, that they accumulate over the course of a day. Nighttime is the point of the 24-hour cycle when our minds have the opportunity to convert short-term memories to long-term ones, and discard the bits and pieces they deem unnecessary.
Another popular theory is that, without the intense, singular focus required for daytime tasks — solving a math problem, say, or trying a new recipe for dinner — our brains are essentially out on recess at night. They have the opportunity to make loose connections, to sort through the more difficult emotions we may be experiencing. It's an explanation as to why we have anxiety dreams and nightmares.
But if you've have had a dream-sharing experience with a friend, it's most likely due to a combination of these theories, along with a little bit of BFF magic.