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Brendan DePue
Most of us have recognized someone as familiar without being able to pinpoint why. Recently, as I was giving a presentation at the University of Colorado, Boulder, I had a nagging feeling of familiarity every time I glanced at a guy sitting in the front row. Where had I seen him before? Should I trust that instinct?
At the end of my talk, he introduced himself as Brendan DePue. I knew the name, as I knew of Brendan’s neuroimaging work on memory suppression effects. The thing was, I was certain that I had never actually met Brendan before.
Memory researchers often use such examples of familiar face recognition to illustrate familiarity-based recognition. In fact, we even have a face-based term for it: The Butcher-on-the-Bus phenomenon. It comes from George Mandler’s example of experiencing familiarity for a face on a bus because the person is actually the butcher, illustrating that feelings of familiarity often stem from seeing a known face outside of its usual context. I often experience this when I see students from my classes outside of the classroom setting.
But face familiarity doesn't always result from seeing someone you know outside of the usual context. Take my familiarity with Brendan DePue for example. When I searched online for his contact information, I found his picture and realized that he looked an awfully lot like Vincent D’Onofrio from Law & Order: Criminal Intent.
“Ah ha!” I thought. “That is why he seemed so familiar.”
Vincent D'Onofrio
In fact, experiences like this are not limited to faces. Take, for example, déjà vu. Researchers have long surmised that déjà vu may be a special case of familiarity-based recognition. Perhaps a situation that is actually new seems familiar because a situation in memory is highly similar to it; you are simply failing to recall the exact situation in memory that is driving that feeling of familiarity.
The experience of familiarity itself may be a form of intuition. In a fascinating study, Bolte and Goschke (2008) reported that people could intuitively tell when a picture fragment came from an intact whole object (like an upright typewriter) as opposed to from a scrambled object, even though they could not identify the object itself. This ability to intuitively recognize patterns is reminiscent of the experience of recognizing a face or scene as familiar without being able to pinpoint why.
What is the purpose of the feeling of knowing something? Is it useful?
In Stieg Larsson’s book, “The Girl with the Dragon Tattoo,” the main character experiences a feeling of familiarity with something while flipping through pages of a photo album searching for clues that will help him crack a case. Larsson writes, “He felt a fresh excitement, and over the years Blomkvist had learned to trust his instincts. These instincts were reacting to something in the album, but he could not yet say what it was.” Many pages later, he writes, “After Berger’s visit in May, he had studied the album again, sitting for three hours, looking at one photograph after another, as he tried to rediscover what it was that he had reacted to.”
Indeed, Blomkvist later had that “ah ha!” moment where he realized what it was, and that piece of information helped him to solve the case.
Perhaps the usefulness of the feeling of knowing is just that: By alerting us to the likely presence of something relevant in memory, it prompts us to continue searching for the answer. At times it might turn out to be something we can laugh at, as in the source of my familiarity with Brendan DePue. But at times it might turn out to be the thing that helps to solve a case or make an important discovery.
