The effect sleep deprivation has on your memory

A typical college student. (http://www.theprepperjournal.com/wp-content/uploads/2014/04/SleepDeprivation.jpg)

We’ve all done it. Staying up late at night to cram for a test or to finish last-minute homework is a common student occurrence (Perhaps you are even doing it now to finish your SC200 blog posts). To perform well academically, however, perhaps we should all seriously consider not procrastinating and sleeping more hours.

A typical college student’s to do list. (http://www.paulthecounsellor.com.au/wp-content/uploads/2011/08/why-do-people-procrastinate.jpg)

A 2014 study authored by Steven J. Frenda, Lawrence Patihis, and Elizabeth F. Loftus of the University of California and Holly C. Lewis and Kimberly M. Fenn of Michigan State University shows that sleep deprivation can increase the risk of false memories. 

To preface, Frenda et. al noted that memories are derived from multiple sources and do not play back like a recorded movie. Thus, false memories can be easily created. For example, 40% of Americans remember the details of the 9/11 terrorist attack incorrectly. In a 2015 follow-up study of 9/11, participants recounted the events after 1 year, 2 years, and 10 years. Despite the participants’ confidence in their abilities to remember what they experienced that day, the results of the study showed that they increasingly added flashbulb memories (affected by media outlets) to their stories. So, it must be emphasized that memories are not consistent.

The Experiment

In the 2014 sleep deprivation and false memory study, 198 undergraduate students with a mean age of 20.3 years were participants.

Null hypothesis: Sleep deprivation has no effect on memory.

Alternative hypothesis: Sleep deprivation has a negative affect on memory.

Before any of the study session was performed, the participants kept sleep diaries for a week.

A week later:

In the news portion of Experiment 1, the participants were asked to read a passage about the 9/11/2001 crash in Shanksville, Pennsylvania. The participants then answered questions based on the passage. The passage also falsely stated that video footage of the crash was spread across the Internet and news. Video footage of the crash had, in fact, not been captured or shared. A polar question on the questionnaire asked whether or not the participants had seen a ground witness’ video footage of the crashing plane. Researchers also interviewed the participants to assess their memories of the recorded incident. The researchers then asked again whether or not the participants had seen footage of the plane crash.

In the misinformation portion of Experiment 1, 2 sets of 50 pictures each were presented at the speed of 35 seconds per photograph to each participant. The first set showed a man burglarizing a parked car, while the second set showed a woman getting her wallet stolen by a thief. About 40 minutes later, participants read a passage for each photo set explaining the pictures. Each passage contained 3 piece of information that contradicted what was shown in the pictures. Participants were not told there would be false information within the passages. About 20 minutes later, the participants then took a multiple choice assessment to test their memories about the pictures. The 3 multiple choices of each question were created so that one was true to the photographs, one was true to the passages, and one was neither true from the photographs or the passages.

Next, another assessment was given to determine whether they believed they learned the information asked in the question from the pictures, the passages, or whether they simply guessed. Thus, researchers could determine if the participants had noticed or remembered seeing conflicting information.

The participants were then divided into groups based on the amount of sleep they acquired over the past week. Thirty-three participants that had an average of 6.8 hours of sleep were in the restricted sleep group, while the 165 other participants were the control group.

The news portion of the experiment yielded mixed results. Based on the questionnaire, only 33% of the control group said they remembered seeing videos of the crash, while a whopping 54% of the sleep-deprived group remembered seeing footage of the crash. These results are significant. However when asked by the researcher directly, 21% of those in the restricted sleep group continued to say they had seen the video, while 20% of those in the control group also continued to say they had seen the video. This 1% difference is not significant.

The misinformation portion of the experiment showed that 38% of the restricted sleep group included misinformation in their responses. Meanwhile, only twenty-eight percent of the control group included misinformation in their responses. These results narrowly missed significant.

Overall, the false memory rate of the control group was at 13%, whereas the false memory rate of the sleep deprived group was at 18%. This is not significant.

This study was meaningful and well-executed because the demographics were random and not extreme in any way. The pool of participants were also of decent size, making the data more reliable. However, the researchers themselves noted that many studies have been done on this topic, and the results are generally mixed. I believe this could be a part of the file-drawer problem we discussed in class, where researchers are not publishing information that does not deliver “interesting” results. This study was not much different from previous studies in that the results are small and only slightly suggest that sleep deprivation affects false memories.

It would be nice if, in the coming years, a meta-analysis is created for this study. As of now, however, few studies have delved into this specific topic. Thus, there is no definitive concensus about whether or not the POV view is true.

If you need another incentive for getting more sleep, this related study of 171 women suggests that sleep increases sexual desire in women. Just another reason to get more sleep!

Personally, I know I forget copious amounts of information on exams if I am lacking sleep, even if (or especially if) I studied the entire night before. So what does this study mean? As a student, you should compare your gains to your losses. If sleeping more (and procrastinating less!) can potentially improve your studying accuracy and retention, then you should seriously consider doing so–especially if the loss is watching one less episode on Netflix!

A typical college student’s mantra. (http://s2.favim.com/orig/150331/episode-fangirl-netflix-obsessed-Favim.com-2610933.jpg)

3 thoughts on “The effect sleep deprivation has on your memory

  1. Grace Anne Walker

    Good post! The study that you chose to share was very interesting with what they chose to be tested on. I was not surprised that lack of sleep affects memory because when your sleep deprived your body is not functioning regularly. One fault that the study had was both groups should have had the same amount of people so that the results are more accurate. This is a link to an article describing why seven hours of sleep will be the best for your health. http://www.wsj.com/articles/sleep-experts-close-in-on-the-optimal-nights-sleep-1405984970

  2. Jessy Severino

    Its funny that this is a blog post topic. My friend and I were talking about how every time he doesn’t get enough sleep the next day he isn’t able to concentrate on what he’s doing and often forgets certain things. I believe that yes lack of sleep can interfere with your memory on a short term scale because our bodies need to rest in all aspects and if you deprive your body of sleep you aren’t going to be functioning and your mind isn’t going to be as sharp as it would if it were rested. Overall this was an interesting post reading the part of media having an influence on people on how certain events played out was pretty cool.

  3. Jackie Michelle Tremblay

    I agree that it is better to get enough sleep and that sleep affects memory. However I don’t think that sleep affects long term memory as much. I think memory in general is unreliable, and whether or not some one is able to correctly recall something that happened far in the past, can be due to any of number of things, and sleep is probably not the main factor. I think sleep probably affects the short term memory more. This post is very interesting, especially the part about media affecting how people recall events.

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