Memory is a willful dog. It won’t be summoned or dismissed but it cannot survive without you. It can sustain you or feed on you. It visits when it is hungry, not when you are. It has a schedule all its own that you can never know. Elliot Perlman

My memory works in a fairly consistent way. When I can't remember something, I struggle without success to stop searching for it. This is the hard part. But it’s important to stop, if you want to recall what you’re searching for.

Finally I give up or get distracted and then, after an unpredictable amount of time, out of nowhere it seems, what I’m trying to recall drifts in. It can be in the middle of the night or when I am doing something else, like typing this sentence, taking a shower or not doing much of anything at all.

You just never know when X’s name will pop in. But more often than not it does--eventually—or I forget about what I was searching for. The mind does so much of its work behind the scenes.

Surely you have had similar experiences and I suspect the phenomenon is rather common. Mind-Pops is the subject of Ferris Jabr’s recent article in the Scientific American. Ferris reviews the work of Lia Kvavilashvii who is one of the few who have investigated this aspect of memory.

Kvavilashvili notes, “But once I started recording them, quite often I would notice that what popped into my mind wasn’t entirely accidental. The contents of the mind-pop had been experienced in the recent past.”

Another kind of mind-pop is the unexpected recollection of a previous event. The older you get, the more often this occurs. A childhood experience, a place you visited many years ago, a friend you haven’t thought of in years pops in. These memories are totally involuntary and seemingly unrelated to anything you are doing.

But are these autobiographical mind-pops quite so random? Perhaps they are related to something in your environment or an incident that “primed” them? Ferris writes, “If a psychologist gives a volunteer a list of words including the word “apple” and later asks the volunteer to write a complete word starting with “app,” the subject is more likely to write apple than “appetite” or “application.”

So perhaps the memory of having lunch many years ago with you high school buddy, Phillip popped in because recently you read a short story by Phillip Roth or a blog about him. Kvavilashvili believes that mind-pops are not random; instead they are linked to our previous experiences and knowledge.

She recalls a mind-pop when the word “Acapulco” sprang into her “consciousness.” after throwing a used bag into the trash, She couldn’t figure out why until a family member reminded her that 45 minutes before they had watched a TV program about the Mexican resort city.

Of course, most of the time the chain leading back to the source of the mind-pop cannot be traced. Still the fact that it often can suggests a mind-pop does not simply appear out of nowhere or represent random neuronal firings, even though the long chain of prior associations is not readily retrievable.