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A few weeks ago, I had the pleasure of giving a talk on Déjà vu at the Museum of Contemporary Art Denver’s “Mixed Taste” series. The series, “Mixed Taste: Tag Team Lectures on Unrelated Topics,” is a fun, gimmicky series in which two speakers on seemingly disparate topics give lectures back-to-back, and the audience attempts to connect the two. My talk, “Déjà vu,” was paired with a talk on Harry Houdini by the Denver magician, “The Amazing Dave Elstun.”
At first glance, it might seem like these two topics have nothing at all in common. Or, it might even seem like what they have in common is something in the realm of the supernatural. Indeed, some people came in expecting “supernatural” to be the link, and were surprised at the major connections that actually emerged in the Q&A session. In fact, I thought that some really neat connections between the two emerged in the session. Here are some of them:
Connection #1: There is a logical explanation for the seemingly mysterious
One connection made between déjà vu and Houdini was that things that seem mystical or mysterious usually have a logical explanation. With déjà vu, it’s a strange sensation that gives a person the sense of a prior experience with what is happening in the present moment, or even a sense of what will happen next, for seemingly no explicable reason. Because the experience is often filled with certainty about having previously experienced the present event while at the same time having knowledge that this situation is actually new, people often wonder if déjà vu is related to past lives or could mean that they are psychic and having a premonition about what will happen next. However, as I have argued here previously, déjà vu is explainable in terms of memory processes, such as the feeling of familiarity, that can operate even when we fail to retrieve something. With Houdini, it’s that he seems to have had this phenomenal ability to escape from situations that should not have been humanly possible. In fact, Sir Arthur Conan Doyle believed that Houdini had paranormal abilities that enabled him to make his fantastic escapes. However, Houdini himself was not a big believer in psychic abilities or the paranormal. In fact, in the later years of his career he made efforts to debunk paranormal claims as well as people who claimed to be psychics. His expertise as a magician enabled him to expose the tricks and techniques of those who were able to fool people into believing that they had paranormal abilities. He writes about this in his book, "A Magician Among the Spirits."
Connection #2: Memory for spatial layouts may be useful for escape
Clearly, Houdini was a master of escape, so this is an interesting connection. As reviewed in Dr. Alan Brown's book, déjà vu most commonly occurs with places. People commonly report déjà vu as a feeling that they’ve been someplace before. In my lab, we have shown that an unrecalled memory of a previously-experienced spatial layout can contribute to déjà vu with places. Undoubtedly, remembering the layout of places is helpful for identifying an escape route. But what about when people fail to recall the previous experience with the current layout and only have a sense of déjà vu? It’s possible that having a mere memory-driven sense about the space can be helpful in having a hunch about which way to go. In this way, déjà vu and similar memory-driven feelings and hunches could potentially sometimes be useful, maybe even adaptive, insofar as having a hunch about how to escape a space could be useful.
Connection #3: Failing to “see” what is going on in the periphery
Magicians (and sometimes pickpockets, as described in this article) often capitalize on people’s attentional abilities and what people are likely to fail to notice going on in the periphery. To link this to déjà vu is interesting, and maybe not a far a stretch when considering that some evidence suggests that memory retrieval itself is a form of attention. Given that attention can be outward- or inward-focused, what is retrieved from memory is what is within the current focus of a person’s inward-turned attention. If déjà vu represents a case of retrieval failure, perhaps it actually is a good example of something in the periphery of your mind, so to speak, that is not within the focus of your attention in that you have not “found” it to retrieve it. In the case of déjà vu, the feeling itself is alerting you by drawing attention to the possibility that something relevant is there in your memory, and that you should keep searching to try to find out what it is. In other words, something in memory that has failed to reach the focus of your attention may be signaling its presence nonetheless.
Connection #4: Does it take away the “joy” to know the why and how?
Is it better to relish in the mystery of it than to find out the why and how of things like how magicians perform their tricks or why we sometimes experience déjà vu? Dave Elstun told the story of someone who had once, after seeing a very cool magic trick, said, “Wait, don’t tell me how you did that. Just let me enjoy this moment.” Perhaps there is something to be said for enjoying the mystery of not understanding something. Of course, as a scientist, I find the most fun part to be discovering the why and how of things.
