What do dreams mean? I was dumped 10 months ago. I couldn't stop thinking about him. Now I barely do, but last night, I dreamed I broke in to his apartment, found him in bed with this gorgeous girl, and punched her in the face. Does this mean I'm not over him?

--Wanna Start Dating

Follow your dreams -- and end up doing five to 10 in the pen for home invasion and assault!

The widely believed myth that dreams are filled with meaningful symbolism is an unfortunate form of what I call Freud reflux -- the "I Dream of Penie" version of a questionable burrito that keeps repeating on you. The assumption that Freud knew what he was talking about comes not from any solid evidence for his claims but, as I wrote in a previous column, probably in part because he "accessorized so credibly, with the cigar, the iconic eyewear, and the groovy Viennese fainting couch."

Psychologist William Domhoff, on the other hand, has done decades of rigorous research on dreaming. He finds there's really no good scientific evidence that dreams have any importance for guiding our lives -- no evidence that they have any function or useful meaning for us (save for the guy in the turban and kohl eyeliner outside the food co-op, for whom dreams are the stuff that timely rent payments are made of).

Domhoff explains dreaming as "intensified mind-wandering" that leads to "imaginative but largely realistic simulations of waking life." Brain imaging of people in REM sleep (a sleep stage often accompanied by vivid dreams) suggests our capacity to dream is "an accidental byproduct of our waking cognitive abilities" and may be a "subsystem" of the "default mode network" of the brain.

This is simply the network of neurons the brain "defaults" to when you aren't doing targeted thinking, like trying to solve some complicated equation or remember some word in French. Your brain doesn't just shut down between these targeted thinking jags. It does what I think of as "background processing," gnawing at problems you were previously focused on -- but it does it beneath your conscious awareness while you're, oh, washing a dish or having sex.

So, in a way, dream time seems to be a kind of cognitive autopilot. In brain scans of people in REM sleep, neurobiologist Yuval Nir sees decreased self-awareness, attention, and memory. There's also reduced "voluntary control" of action and thought -- which is why, when dreaming, we cannot control "the content of the dream," like by changing the channel from HesWithSomeHussy!TV. Nir also finds that there's often -- surprise, surprise -- greater emotionality when dreaming. (Presumably, you don't go around punching your ex-boyfriend's dates in your waking life.)

However, Domhoff says that in many instances, dreams "dramatize ongoing emotional preoccupations." These are sometimes unhealthy or at least unhelpful. You'd think you could just try to avoid thinking those thoughts during your waking hours. Unfortunately, research by the late social psychologist Daniel Wegner suggests otherwise.

Wegner, famously, instructed research participants, "Try not to think of a white bear." This is a failed proposition from the start, because your mind sweeps around to check whether you're avoiding bear-pondering -- thus leading you to think about the bear. In short, Wegner found that trying to suppress thoughts made them come back with a vengeance. The same was true when he later had subjects try to suppress thoughts just before going to sleep. These subjects were much more likely to have those thoughts be all "We're baaaack!" in their dreams.

But -- good news -- there is a way to outsmart your brain's yanking you back into the same old abyss. Psychologists Jens Forster and Nira Liberman found that you can probably keep yourself from endlessly revisiting a thought if you simply admit that not thinking of it is hard. As I explain in my new book, "Unf*ckology: A Field Guide to Living with Guts and Confidence," their solution "probably sounds too simple to be real, but it makes sense. Removing the need to patrol your thoughts also removes the mental sticky note that tells you to keep going back into Thoughtland ... to see how well you're doing."

In general, you should try to avoid ruminating -- pointlessly rechewing the past, like your mind's a sadistic TV station always showing the same disturbing rerun. Moving forward takes thinking about the past in "forward" ways -- basically, by making meaning out of it. So when you find yourself reflecting on this relationship, remind yourself to put the right spin on it: looking at it from the standpoint of what you've learned -- what you'll apply to make your relationships work better in the future. Before long, you could be on a date again -- and I don't mean one of his, with binoculars from a car across the street.