By Yana Weinstein

(cover image by Elisa from Pixabay)

I’m very passionate about memory. I’ve dedicated most of my adult life so far to examining how our human memory works. But why?

Well, think about your life. Think about how you define yourself, who you are. Maybe you see yourself as a hard worker. That might be because for many years you have proven yourself through working hard, and you remember working hard a lot.

Maybe you think of yourself as a parent. That conjures up memories of your child’s birth, or adoption, or first bruise that you blamed yourself for, or first day at school when you couldn’t believe they were already that old.

Maybe you think of yourself as kind and helpful to others, and immediately remember that time you drove over to your best friend’s house in the middle of the night to deal with an emergency.

Your very identity is most likely full of things you remember yourself doing. Maybe you also have an identity that is aspirational, partly projected into the future, full of lofty goals – I will get my Bachelor’s degree, I will start my own business, I will retire and live in Florida – but what do we do when we imagine this future? There has been a flurry of research into “future mental time-travel”, and the leading theory is that it involves all the same processes as remembering (1). What we’re actually doing when we’re envisaging our future might involve taking bits and pieces of things we’ve experienced – be it in our own lives, in books, or in movies – and splicing them together to form a new imagined situation (2).

But our self-concept is not the only thing we need our memory for. Actually, I would argue that everything we do requires memory in some form or another. That might seem like an extreme statement, but here are some examples. Note that these are just a few specific examples, and in no way do they encompass all of the ways in which we rely on memory!

• Remembering names. Some of us might say we are “bad with names”, but ultimately most of find that some people’s names – such as those of the members of our family – are much easier to bring to mind, and our ability to recognize our classmates' names remains very high years after we leave school (3). This is because we’ve had many opportunities to practice using those names over and over again in the context of a personal relationship.

• Remembering whether we’ve done something. Has this ever happened to you? You go to take your medicine, but you can’t remember whether you’ve already taken it…uh oh. The process that prevents her from being sure is called interference, and is a very common and serious problem for people (especially older adults) who are on a lot of medications and have poorer memories (4). Interference also comes up in many other real life situations: for example, remembering where you parked your car on a given day, when you park it in the same lot very day (5).

• Remembering to do something in the future. Prospective memory allows us to be able to plan to do something, like take a pill at a certain time in the future, and this particular type of memory is strongly affected in older age (6).

• Being able to comprehend speech. When you are listening to someone speak, you have to integrate the words they are saying one after the other, as you do not hear them simultaneously. If you instantly forgot each word as soon as you heard it, you would just hear a set of individual words that would not come together to create understanding. The process we use for this type of in-the-moment sense-making is called working memory (7).

• Remembering how to do something. Sometimes, you’re able to remember a procedure or set of actions without really being able to describe it. For example, you can play the piano, hit the perfect volley in tennis, or you’re much faster at typing. These skills all require a form of memory, too – implicit memory (8). The infamous amnesic patient H. M. showed us that even when our explicit or declarative memory fails – that is, we cannot describe our memories – implicit memory may remain intact (9) - though the idea that there is a clear distinction between these two systems has been challenged by some (10).

And yet, despite this rich variety of functions, memory has recently come under fire. Some claim that now that we have The Internet, we no longer need to worry about memory. While there’s a lot of hype about the internet replacing our memory, humans have actually been relying on external memory systems for years. Books contain a wealth of information and have been around for centuries, and we’ve been writing memos for ourselves (notes, lists, and reminders) for many, many generations; one does need to be a “digital native” in order to use external memory resources adaptively (11). Having said that, a fascinating line of research is now examining the cognitive consequences to these behaviors, called “cognitive offloading” (12). For example, one set of studies showed that in some situations, we are more likely to forget something we took a picture of than something we just looked at (13).

I recently came across an article that I won’t link to, which posed the following question with respect to the decline of memory: “Ask yourself, why don’t I just use my computer?”. The answer to that question should be obvious: because you can’t use a computer without using your memory first. We might be adapting from remembering information to remembering how to obtain that information from external sources (14) – but that still requires memory!

If you enjoyed this post, you may be interested in some of my other posts on memory:

Are Our Memories Like Libraries?

How long is short-term memory? Shorter than you might think.

References:

(1) Szpunar, K. K., Watson, J. M., & McDermott, K. B. (2007). Neural substrates of envisioning the future. Proceedings of the National Academy of Sciences, 104, 642-647.

(2) Botzung, A., Denkova, E., & Manning, L. (2008). Experiencing past and future personal events: Functional neuroimaging evidence on the neural bases of mental time travel. Brain and Cognition, 66, 202-212.

(3) Bahrick, H. P., Bahrick, P. O., & Wittlinger, R. P. (1975). Fifty years of memory for names and faces: A cross-sectional approach. Journal of Experimental Psychology: General, 104, 54-75.

(4) Insel, K., Morrow, D., Brewer, B., & Figueredo, A. (2006). Executive function, working memory, and medication adherence among older adults. The Journals of Gerontology Series B: Psychological Sciences and Social Sciences, 61, P102-P107.

(5) da Costa Pinto, A. A. N., & Baddeley, A. D. (1991). Where did you park your car? Analysis of a naturalistic long-term recency effect. European Journal of Cognitive Psychology, 3, 297-313.

(6) Brandimonte, M. A., Einstein, G. O., & McDaniel, M. A. (2014). Prospective Memory: Theory and Applications. Psychology Press.

(7) Daneman, M., & Merikle, P. M. (1996). Working memory and language comprehension: A meta-analysis. Psychonomic Bulletin & Review, 3, 422-433.

(8) Roediger, H. L. (1990). Implicit memory: Retention without remembering. American Psychologist, 45, 1043-1056.

(9) Gabrieli, J. D., Milberg, W., Keane, M. M., & Corkin, S. (1990). Intact priming of patterns despite impaired memory. Neuropsychologia, 28, 417-427.

(10) Berry, C. J., Kessels, R. P., Wester, A. J., & Shanks, D. R. (2014). A single-system model predicts recognition memory and repetition priming in amnesia. Journal of Neuroscience, 34, 10963-10974.

(11) Loh, K. K., & Kanai, R. (2016). How has the Internet reshaped human cognition? The Neuroscientist, 22, 506-520.

(12) Risko, E. F., & Gilbert, S. J. (2016). Cognitive offloading. Trends in Cognitive Sciences, 20, 676-688.

(13) Henkel, L. A. (2014). Point-and-shoot memories: The influence of taking photos on memory for a museum tour. Psychological Science, 25, 396-402.

(14) Sparrow, B., Liu, J., & Wegner, D. M. (2011). Google effects on memory: Cognitive consequences of having information at our fingertips. Science, 333(6043), 776-778.