The third main type of memories are episodic memories. These are often called “autobiographical” memories because they are memories of things we have personally experienced. What we saw. What we heard. What we did. This type of memory is most closely associated with our sense of self because it is the narrative of our lives. Furthermore, it’s episodic memory that allows us to mentally travel back in time to revisit something that happened to us years (or decades) ago.
But even our clearest autobiographical memories aren’t 100% episodic. Because our brains only remember what they think will be important to us in the future, we rarely remember all the details of something we experienced. So, when we recall something that happened to us in the past, our episodic memories of it are often incomplete. To compensate, our brains automatically fill in these gaps with semantic memories, including facts and the common patterns stored in schemas. This combination allows us to recall what appears to be a complete memory. But since it’s not entirely composed of the specifics stored in episodic memory, it won’t necessarily be an accurate reflection of what actually happened.
For example, if you’ve ever been to the big island of Hawaii, you probably flew into and out of Kona International Airport. After passing through the airport, your brain decided if any details of the airport were important for your future. If it decided they weren’t, then it wouldn’t save any information in your episodic memory.
So, later, when you try to recall what the gate area at Kona airport was like you would probably remember it being similar to most airports you’ve visited (based on your semantic memory): Rows and rows of uncomfortable black chairs, overpriced restaurants and stores, and a long, enclosed jetway that takes you from the gate to the plane. This, despite the fact that Kona International Airport is almost entirely outdoors, with wooden benches instead of chairs and, that to board your plane, you walk onto the tarmac and then up a portable ramp.
To you, the memory may seem crystal clear, with no hint it’s a composite or that it isn’t an accurate reflection of what you personally experienced. And, most of the time, this fiction created by our brains is no big deal. It serves the purpose: to quickly help us navigate our world.
But when we (or someone else) points out the flaws in our memory it can be upsetting because “we” were there, but can’t seem to remember what actually happened.