Think, for a moment, about one of your cherished childhood memories, one of those sepia-tinged recollections that you’ve repeated countless times. I’ve got some bad news: big chunks of that memory are almost certainly not true. According to scientists, the brain is a consummate liar, a bullshit artist of the first order. To remember is to fabricate.
Why is memory so inherently dishonest? To make a long story short, it’s now pretty clear that the act of remembering a memory changes the structure of the memory itself. (This is known as memory reconsolidation; Freud called it Nachtraglichkeit, or “retroactivity”.) My favorite analogy is that, while we used to think of episodic memory as a “save” function in the brain (the hippocampus is the hard drive) we now know that every memory is really a “save as”. To recall is to create a new file, and instantly overwrite what came before.
Obviously, this has big implications for the veracity of memory. It shows us that every time we remember anything, the memory is altered in the absence of the original stimulus, becoming less about what you remember and more about you. So the purely objective memory is the one memory you will never know. And the more you remember a memory, repeating it to yourself and others, the less honest that memory becomes.
But wait, it gets worse: according to a new PLOS One paper by German researchers, a bad night of sleep can make you even more dishonest than usual. While it’s long been known that we make many of our memories while dreaming – this is why it’s so important to get a good night sleep after studying for a test – it turns out that sleep deprivation causes us to make up memories.
The scientists conducted a rather sadistic experiment, forcing people to stay awake for up to 44 hours at a time. The end result? The insomniacs were much more likely to develop false memories. (As Freud pointed out, the most dangerous aspect of false memories is that they feel true.) The good news, though, is that there’s a cheap and easy cure for such unintentional lies. When people drank a cup of coffee just before they recalled the memories, the dishonesty disappeared. Caffeine is a truth serum.