Have you ever wondered why some things come back to you seemingly out of the blue? You think to yourself, “That’s funny, I haven’t thought about that in years.”
Actually, it’s better than funny. The science behind how memory works is fascinating and cool.
Obviously, “How Memory Works” is a topic far beyond the scope of a single blog post. But it is fun to take a look at what scientists call episodic or autobiographical memories—the events of our pasts. Why we remember the things we do.
The memories we have and are able to recall are critical to how we think of ourselves. Researchers Martin A. Conway and Christophe Pleydell-Pearce explain, “autobiographical memory is of fundamental significance for the self, for emotions, and for the experience of personhood, that is the experience of enduring as an individual, in a culture, over time.”
The ability to retrieve memories starts with the way the brain stores memories.
Part of the wonder of how we recall memories is in the way they are stored, or encoded.
When we envision our brains, we tend to think of memories being stored in a specific place in the brain. For instance, we might think our memory of riding a horse when we were ten is stored in a single discrete location in the brain, much like a file is saved on a hard drive. However, that’s not how it works.
Our memories are stored in a much more complex, wonderful way. That memory isn’t “stored” in any one place. Instead, it’s encoded in numerous places in the brain, with various pieces of what scientists know as “context.”
Much of this context amounts to individual bits of sensory perception. For instance, the feelings related to that memory, such as the feel of the horse underneath you or the feel of the saddle are stored in different places than the smells you experienced. The brain stores each individual component of that experience—the creaking of the saddle; the snorting of the horse; if we went fast, the wind against our skin; if the horse ran us into a tree, the feel of branches against our skin –in various locations in our cerebral cortex.
Despite the fact that they are stored in separate places, those individual pieces of context are encoded together. They remain interrelated.
Additionally, those pieces of sensory context translate into memory cues. And, because they are all stored separately, any one cue can bring back that memory.
In the 1960s and 70s, a researcher named Endel Tulving conducted several studies & found that subjects were able to remember more when they were surrounded by the same external cues as they were at the time the memory was encoded. (Read more about Tulving’s research)
That goes a long way to explaining why we remember some things while other memories elude us. We’ve all experienced that. Sometimes, we’ve stumbled into those cues, perhaps by going back to our elementary school. We might tag along with someone to a 4-H fair and smell the horses, hear their whinnies and snorts, hear the creaking of saddles… and suddenly we remember a long forgotten horseback ride.
We remember things when our brains experience the same or similar sets of sensory cues as they did at the time those memories were stored.
There’s another important context—and cue—for how we remember past events.
Our emotions play an important role in explaining why we remember some things but not others .
Since Sir Francis Galton studied the phenomenon back in 1879, scientists have known that emotional context plays an important role in the retrieval of memories. However, scientists continue to study the phenomenon. The National Institutes of Health recently published a study by Tony Buchanan who found that “Emotional events are often remembered with greater accuracy and vividness (though these two characteristics do not always go together) than events lacking an emotional component.”
Going back to that horseback ride, if we liked horses and we went on a boring little pony ride—going around in slow circles—that memory won’t have too much of an emotional context.
However, if you were terrified of horses and somebody made you ride one, and you spent the ride in terror, clinging on for dear life, your brain might encode that memory as emotionally significant. Likewise, if you loved horses and riding that horse was one of the most exhilarating things you had ever done in your life, this memory would have a strong emotional context. Which explains why if you are somewhere and you see a horse’s saddle, smell leather or hear the clip-clop of hooves, that emotional response comes back to you. As you remember, all the other information encoded with those sensory memories might also come back
If your memory was emotionally significant, any one of those sensory cues or context might bring that memory to mind. If there was less emotional context, it might take more than one cue.
Immerse yourself in sensory rich environments when you’re trying to remember the events of your past. Go back to the places of your youth, bake that favorite, pie, or visits the county fair.
When you’re in the midst of a moment you hope you’ll never forget, drink it all in. Smell, feel, listen—and most of all—let yourself go emotionally. Enjoying the moment might be as much of a key to remembering it as photographing it.
Richard C. Mohs, Ph.D., How Human Memory Works
Martin A. Conway and Christophe Pleydell-Pearce, The Construction of Autobiographical Memories in the Self-Memory System
Tony W. Buchanan, Retrieval of Emotional Memories