Virginia Hughes has an article at National Geographic talking about the possibility of using electrical shocks to erase memories. The shocks depend on upon the fact that every time we recall a memory, we essentially rewrite it. Due to this constant rewriting, I’m not even sure it’s accurate to say we have long term memories, only memories of memories of memories.
This reminds me of a problem we used to have back in the pre-digital recording days. If someone wanted to make a copy of an audio or video tape, they could do it, but since it was an analog recording, the copy lost some of the fidelity of the original. If their friend then tried to make a copy of the copy, more fidelity was lost. Until after a few generations, the copies were virtually useless. (The music and film companies back then didn’t have to worry about copy protection because pirating wasn’t really worth the effort.)
I strongly suspect our long term memories are like that, except unlike the blighted video tapes we might have tried to watch, we’re not aware of just how much fidelity our memories have lost. Each time we recall a memory, it loses a little bit of fidelity.
This is on top of the fact that when we do commit something to memory, it’s consolidated with other memories. We don’t remember most details about a memory; most of those details are simply categorized based on prior knowledge. As a result, as those categorizations get revised over time due to new experiences, so do the memories.
This issue of recalling memories is a bit of a double edged sword. If we don’t recall memories from time to time, they’re probably in danger of disappearing. (Our ability to learn new things is probably intimately related to how well we can discard old unimportant memories) But if we do recall them, they become compromised. Short of video taping events (digitally now) or keeping a journal, I don’t see any way out of this conundrum.
The important thing to realize about this, is just how fallible our memories actually are. It’s why, as Hughes described, the idea of lost childhood memories has now become such a discredited phenomenon.
Eyewitness testimony of just one witness should never be taken as conclusive evidence of anything. Given the scientific evidence that has accumulated on this, it’s a travesty that anyone in this country ever still gets convicted by such single person testimony. Even multiple witnesses that aren’t independent from each other should be suspect. Not because they may have colluded in dishonesty, but because they could inadvertently influence each other’s memories.
For an expert take on this issue, check out Elizabeth Loftus’s TED talk.
- About Memory (memoryforward.wordpress.com)
- What is spaced repetition ? The science behind it (cardkiwiblog.wordpress.com)
- The Internet & Creativity: An Assault on the Essence of Humaness (bricknotespress.com)
- We Are Not Our Memories Anymore (talesfromtheradiationage.wordpress.com)
- Zapping the brain can help to spot-clean nasty memories (nature.com)
- Shock Therapy Can Erase Unwanted Memories: Is ‘Eternal Sunshine of the Spotless Mind’ Possible For PTSD, Depression Sufferers? (medicaldaily.com)
- Researchers Wipe Out Unpleasant Memories in Psychiatric Patients (medindia.net)
- Erasing Painful Memories With Shock Treatment (healthland.time.com)
- Absolutely shocking: electrocuting brain can wipe unpleasant memories (wired.co.uk)