CogBlog – A Cognitive Psychology Blog

We live in a world today that is constantly bombarding us with stimuli. Even a simple morning routine of getting to school or work shows how much information we have presented to us. Say we turn on the TV to look at traffic reports; we will see which celebrity is promoting his or her new film, which route to take and the new product we absolutely need to have. We have to make breakfast and get ourselves ready to leave. On the way there, we could run into advertisements on billboards and a new song we like on the radio. By the time we finally arrive, so much has been stored away in our memory. Yet how many times has it happened that we distinctly remembering hearing a specific song on the radio or which person was on the news that morning and someone else confidently tells us we are mistaken? How can we so strongly and vividly remember something when it did not happen at all?

A person’s memory store is a flexible and ever-changing entity. Nothing, absolutely nothing at all, is completely fixed; everything is susceptible to some sort of change whether it be in a positive or negative direction. In his book, the Seven Sins of Memory, leading memory researcher Daniel Schacter outlines some of the ways in which our memories can be altered. In the study of psychology, the memories we have stored away from previous events are our long-term memories. These long-term memories can go as far back as an early childhood memory of the first day of school or as recent as what we ate for breakfast this morning. Short-term memory, or the memories associated with a very recent event, goes through rapid decay; our short-term memory can only hold on to information for 20-30 seconds. In addition short-term memory has limited capacity, meaning that it can only hold so many items, about 7. Memories from the short-term stores get transferred into long-term, where there is an unlimited capacity and duration for memory. However, these memories can be altered. Some of the more relevant “sins” to the problem at hand are misattribution and suggestibility. The “sin” of misattribution states that we can confuse the source of a piece of information; this explains how we might confuse which celebrity was on the TV yet we remember exactly what he or she said. The “sin” of suggestibility reveals that after a memory is made, a false suggestion made by some other person or source can lead us to change our memory; for instance if our friend told us that we heard a specific song on the radio that was not actually played, we might later recall hearing that song on the way to work. We can be confident in our recall of an event, like the events of our morning routine, yet our memory might not be as correct as we think it is!

We undergo so much in the average day that requires us to recall past events. For instance on our drive to work, we remember which turns to take and when to leave before traffic hits. However, do you ever remember making a wrong left turn when making that left seemed like the correct turn to make? Sometimes we simply “remember” something incorrectly, even though it seemed correct in our minds. That brings into question the idea of how recall of memory can change it: how much influence does it really have? A 2013 study conducted by Peggy St. Jacques and Daniel Schacter at Harvard University sought to answer the question of how reactivation, or recall, of specific memories can affect them when we later try to remember them. These researchers had participants take a guided tour of Harvard’s art museum and during this tour, pictures were automatically taken from the perspective of the participant. These photographs represented what the participants actually saw. Subjects were then asked to return 48 hours later for a recall test. In this recall test, subjects viewed a video montage of 4 pictures they had taken and 2 that were of objects in the museum that were not on their tour. The subjects were measured on a yes/no response (that is if they had seen the object on their tour in the photograph) and response time to make that judgment.

The subjects were shown sets of two pictures shown side-by-side; these photographs were either a “match” or a “mismatch”. The former had two pictures that had both been taken by the subject and the latter contained one picture from the subject and one “lure” photograph, an image of an object not seen by the subject. A “hit” was a subject remembering a set of pictures correctly and a “false alarm” was the same subject falsely “remembering” seeing a pair of photographs they had not previously seen. Relating this to everyday occurrences, this setup is similar to being shown the normal way you drive to work and then being shown an alternate way you do not usual use. This process allowed the researchers to test to learn about how often and the manner in which we falsely “remember” something.

A second study was conducted with the same conditions of study 1 but instead of a match and mismatch recall, the subjects were shown just a single photograph at a time. The researchers instead manipulated the perspective of the images. In this study, a “match” was defined as a picture taken by the participant whereas a “mismatch” was a control image in which the perspective had been altered; for instance the “mismatch” could be an image of the same painting you had seen on your tour but instead from the viewpoint of a 12 foot tall person. The subjects were shown “target” and “lure” photographs; the former was a photo of the subject’s museum stops during their tour and the latter was an image of an object not seen on their tour. The participants had about equal percentages correct for both groups, showing there was no difference made by the change in perspective.

Surprisingly subjects were more confident in their memory for false alarms than for hits in the second study. This shows that there is a great deal of inaccuracy the more confident you are about a specific memory. Also the greatest affects of false recall were seen with the increase of recall. In this study, the experimenters also manipulated the number of sets given before a judgment call had to be made on if the participant had seen the object in the photo or not. Thus the more one tries to remember an event without feedback, the more likely one is to make a mistake. For instance once you finally get into work ,you attempt to tell your coworkers whom you had seen on TV that morning. However, it does seem harder to remember when you go over it in your head multiple times, trying to figure out who really was giving that interview.

Retrieval of memories does alter them for later recall. Because memory is a constantly evolving process, retrieval is able to modify memory. A simple retrieval cue can substantially change how we remember something, even inserting a false memory into our stores. This study shows that not all memories are recalled equally. The power of a memory can dictate how reactivation influences modification of that memory.

To summarize no memory is truly safe from being altered. No matter how confident we are that we really remembered something, we can easily falsely “remember” something. The way in which we recall a certain memory is paramount in how it gets retrieved. So next time you have an argument with a friend over a recent event, just remember that your confidence level is not a good indicator of how “right” you might be. Even something that happened a few hours ago could be recalled falsely so be careful before using your first-hand account to win that argument! Every memory that can be retrieved is susceptible to change when we try to remember them but the way in which we “remember” something can predict how true that memory really is.

References:
St. Jacques, Peggy L., and Daniel L. Schacter. (2013) Modifying Memory: Selectively Enhancing and Updating Personal Memories for a Museum Tour by Reactivating Them. Psychological Science