Where memory and emotion meet
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Blog: Memory Lane

Blog: Memory Lane

Learn about memory, emotion, aging, and other topics in this blog written by Boston College students and members of the CANLab

 

Why are Emotional Memories Easier to Remember (by Shea O’Malley)

If I were to ask you to recall some of the most prominent memories in your life, where do you think your mind would go first? Would it be what you ate for breakfast exactly 5 days ago or would it be that time that you got lost as a child? Most people can remember where they were and what they were doing on 9/11, or what the weather was like when their first child was born. However, nobody remembers what they were doing on September 10th, 2001, or if it was sunny on a random day over 20 years ago. Now, this isn’t some grand discovery. Everyone is aware that certain memories stick in our brains because they hold more importance than others. But what exactly makes one memory more important than the next? Emotion. Memories linked with strong emotions often become seared in the brain. René Hen, PhD, professor of psychiatry and neuroscience at Columbia University claims that, “It makes sense we don’t remember everything…We have limited brain power. We only need to remember what’s important for our future well-being” (Columbia). Therefore, all the repetitive and mundane everyday actions that occur are erased from our memory after a short period of time because there is simply no room to store them.

People generally remember moments or experiences of fear in their lives even if it occurred in their childhood. This is due to the fact that fear is not just a momentary feeling as many believe it to be. In fact, fearful emotions serve as learning experiences that are critical to us on a survival level. When we encounter a fearful situation, the neurons in our brain record the details so that we can remember to avoid similar situations in the future. For example, if you had a near-death experience by almost drowning in the ocean, your brain will tell you to be cautious or avoid swimming because it remembers the fear that you had in that moment.

In addition to emotions such as fear or extreme joy, our brains tend to remember highly surprising events with great detail. Dr. Elizatbeth Kensinger introduces the concept of the “flashbulb memory,” a term coined by Brown and Kulik in 1977. These two authors argued that surprising and abnormal events trigger a special memory mechanism in the hippocampus that causes the moment to be recorded with picture-perfect accuracy. A study was conducted to prove this by interviewing people fourteen years after President Kennedy was assassinated. Nearly everyone that participated in the study was able to recall minute details about their day including where they were, what they were doing, and how they heard the news. It is important to note that there is no true way to check for the accuracy of these memories. The important part, however, is that these people believed they remembered these facts with great confidence and vividness.

While these eyewitness accounts are said to be remembered with considerable accuracy, even emotional memories are subject to distortion. Dr. Kensinger discovered in her studies on emotional memories that people’s reports of these events are subject to change over time, often without them realizing. Despite this, the individual’s confidence in their memory does not waiver leading to the conclusion that the “hallmark of an emotional memory may be the subjective vividness with which it is remembered rather than the accuracy with which the event is retained” (Kensinger).

Even after many years of research, scientists are still unsure about why these memories recorded by the brain’s hippocampus become so strong. It is evident that they do, but why? In an attempt to find out, Hen and Jessica Jimenez from Columbia University placed mice into a foreign environment and recorded the activity of hippocampal neurons that reach out the amygdala. Then, they recorded the neural activity a day later when the mice tried to retrieve the memories of their experience. They discovered that these neurons became synchronized when the mouse went to recall the memories from the previous day, reinforcing that neurons that respond to the foreign and scary environment send information to the fear center of the brain. Therefore, synchrony is a critical aspect in establishing detailed memory. “The greater the synchrony, the stronger the memory” (Jimenez). There is still a lot of mystery surrounding how and when synchronization occurs, but that may be the next step in revealing the inner workings of the brain.

There are three phases of memory that must occur successfully for an event to be remembered to the fullest extent. First, sensory registers must record the event and encode it. Then, the event needs to be consolidated into a stable and lasting representation, Lastly, the event must be retrieved (Kensinger). Memories that hold significant emotion have specific processes that are engaged at all three stages, increasing the likelihood of the information being remembered. In addition to memories with emotional value attached, positive and negative arousing memories are more likely to be remembered than neutral ones because of the same encoding processes.

Another interesting aspect to emotionally-charged memories is the way that stress affects both memory storage and recall. Stressing about a final exam 20 minutes before taking it may seem like a bad idea. However, this can actually assist you in recalling the information that you studied more clearly. But if you were to be stressed and worrying about the test all day, by the time you sit down to take it your hippocampus and amygdala will be exhausted. This will result in a more difficult time remembering everything you studied. This is because cortisol, a hormone released when you’re stressed, triggers two different processes in the memory-based areas in your brain. The first process encourages the neurons in the amygdala and hippocampus to be more responsive making it easier to form and access memories. The second process does the exact opposite, slowing your brain down and making it more difficult to recall information.

Overall, the connection between memory and emotion in the brain is a fascinating, complex topic that is still being researched today. Scientists continue to discover new information regarding their connection. However from what we currently know, it is evident that emotional memories are better remembered because of the three stage process that our brains use to encode, consolidate, and retrieve information. So we should all be thankful for our amygdalas and hippocampuses because without them, life would not be as meaningful as it is.

Works Cited

“How Do Emotions Affect Your Memories?” Healthline, 10 July 2022, https://www.healthline.com/health/mental-health/how-does-emotion-impact-memory.

Kensinger, Elizabeth A. “Remembering the Details: Effects of Emotion.” Emotion Review, vol. 1, no. 2, 2009, pp. 99–113. PubMed Central, https://doi.org/10.1177/1754073908100432.

“Why Are Memories Attached to Emotions So Strong?” Columbia University Irving Medical Center, 13 July 2020, https://www.cuimc.columbia.edu/news/why-are-memories-attached-emotions-so-strong.

Elizabeth Kensinger