Our brains, in many ways, remain the undiscovered country of the human body, and we are constantly learning new and interesting things about it. Like how our memories are completely and utterly unreliable, and we may in fact be lying to ourselves on a daily basis.
The brain, and neuroscience in particular, has always fascinated me. I am by no means an expert; I am just constantly intrigued by how the brain works, how it interprets the world around us, how even the slightest damage to the brain can cause radical and irreversible change.
When we think of memories, we like to believe we are reliving events exactly as it happened, with no degradation of fact or altering of events. Neurologists, psychologists, and criminologists disagree and have been telling us for years now how individual perceptions can be altered, which is having an effect not only on the study of the brain but in the justice system as well. Even though the brain continues to develop well into our 40s, how it remembers events degrades over time, and it may not exclusively have to do with our age.
Because when you remember a life event, you are remembering the last time you remembered it, not the actual event.
A lot of people think of memories like they would a file stored in a cabinet somewhere. When you want to remember something, you go fetch it from the cabinet, read the file, then put the file back in the cabinet so you can find it next time.
When we remember something, we fetch that memory from where it is stored in our brain, and then modify it. This modification overwrites the original memory, with new brain connections created when a memory is formed, and the “new” version is never perfect. The modified memory is heavily influenced by the context in which we are remembering the memory. A bad or traumatic memory will have a different reaction than a highly positive one. The very act of remembering something changes that memory in your head. Once we’re done remembering it, the brain then “re-files” that memory to be retrieved again. But the original memory is gone, replaced with an imperfect version of that memory.
At least as far as we know today. For example, there are “eureka” moments where the more we reconstruct a memory, the more we remember things that may have been thought lost or modified to the point of fiction. As with anything science-based, current cognitive theories may be changed with greater research, and memory reconsolidating theory is still relatively new.
If you have twenty minutes or so, I recommend this podcast: http://www.radiolab.org/story/91569-memory-and-forgetting/
In case you’re worried about forgetting important life events as they happen, don’t worry! Everything that you are experiencing is happening 80 milliseconds in the past. Which means we won’t even experience the most impactful event of our lives: death. Because we’ll be too dead to remember, even for a millisecond, our final moment of existence.