Memory and imagination
I’ve been thinking about things like this lately, so it interests me a lot. Though it probably would even if I hadn’t been thinking about it – it probably would have started me thinking about it.
Humans are born time travelers. We may not be able to send our bodies into the past or the future, at least not yet, but we can send our minds. We can relive events that happened long ago or envision ourselves in the future. New studies suggest that the two directions of temporal travel are intimately entwined in the human brain. A number of psychologists argue that re-experiencing the past evolved in our ancestors as a way to plan for the future and that the rise of mental time travel was crucial to our species’ success. But some experts on animal behavior do not think we are unique in this respect. They point to several recent experiments suggesting that animals can visit the past and future as well.
They have to go by themselves though. That’s what I was thinking about recently – the fact that they can’t discuss the past with anyone, or inform anyone about it, or be informed about it.
Endel Tulving, a Canadian psychologist, defined episodic memory as the ability to recall the details of personal experiences: what happened, where it happened, when it happened and so on…Episodic memory was also unique to our species, Dr. Tulving maintained. For one thing, he argued that episodic memory required self-awareness. You can’t remember yourself if you don’t know you exist. He also argued that there was no evidence animals could recollect experiences, even if those experiences left an impression on them.
Some researchers are skeptical, and have done experiments that they take to indicate something like episodic memory; other researchers are skeptical.
“Information is not really what characterizes mental time travel,” Dr. Suddendorf said…Episodic memory also depends on many other faculties that have only been clearly documented in the human mind, Dr. Suddendorf argues. He said he believes it evolved after our ancestors branched off from other apes. The advantage lay not in knowing the past, however, but in providing “an advantage for predicting the future,” he said…Daniel Schacter, a psychologist, and his colleagues at Harvard University recently studied how brains function as people think about past experiences and imagine future ones.
That interests me because I’ve long been interested in the fact that there is no real difference between remembering something and imagining it – no phenomenological difference. It’s interesting if remembering past experiences and imagining future ones are essentially the same adaptation.
Constructing an episodic memory causes a distinctive network of brain regions to become active. As a person then adds details to the memory, the network changes, as some regions quiet down and others fire up. The researchers then had their subjects think about themselves in the future. Many parts of the episodic memory network became active again.
There you go. And that’s why memory is so unreliable – it gets mixed up with imagining, and we not only don’t know how to disentangle them, we don’t even know when they’re tangled.