Amygdala-to-hippocampus communication and reactivation of negative memories | Hacker News Reader

Amygdala-to-hippocampus communication and reactivation of negative memories

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67 pointsmerrier11 comments

> For example, if someone is bitten by a dog, he or she may become anxious around dogs of all breeds and sizes

While often not helpful, this doesn't seem like a brain defect. If a class of things causes you severe trauma it seems the natural response would be to recoil from that class of things in the future.

My uncle’s dog grabbed me by the foot and put me on the ground when I was three. The whole incident was over in about two seconds. I wasn’t physically hurt. But I was afraid of dogs for years afterward.

I think the “defect” part is that the panic and anxiety remains even in the face of a vast amount of new information and change. It makes a lot of sense for three-year-old me to fear that dog and be at least cautious of other dogs. It didn’t make any sense for teenage me to be afraid of obviously friendly, familiar dogs who I’ve seen interact with family or friends countless times.

Its said often that our ability to learn, but not unlearn, encapsulates most human progress as well as defeat, both at a personal and global level.

Selecting to keep people away from any potential danger above the level of 0 seems like a fairly good design. You're not paralyzed, merely cautioned, and then your offspring will inherit whatever level of that fear or worry from you based on if and how you've learned to trust what dogs are safe. If a dog attacks you at 3 years old then your environment isn't all that safe - and it makes sense then you may not have guardians who can adequately protect you or keep you in a safe environment. There are tools however to lessen and/or remove such negative conditioning, and it makes sense that that would require actual directed/focused work than just randomly being unafraid of something dangerous - and perhaps better to heal trauma closer to the trauma so neural pathways don't evolve/expand into everything for years or decades.

E.g., if you are hurt by a person, and you become afraid of that person (or people with those characteristics), that is helpful. If you are hurt by a person, and you become afraid of people... that is not so good. If that happens, how to treat?

This article suggests an approach that might allow emotional memories to be "balanced" through some kind of neuromodulation. Promising.

There are multiple layers to the solution which all relates to the pressure on your nervous system, what baseline stress/pressure you have - which ties into stress/factors including inflammation.

Many people self-medicate with inflammation without realizing it, inflammation having a depressant effect - and many foods causing inflammation, meaning our connection to our bodies and feelings are suppressed some to heavily depending on inflammation (and how long we've used food-as-a-coping-mechanism/medication).

Cleaning up diet as much as possible, reducing inflammation as much as possible - includes working towards a healthy weight and water fasting + intermittent fasting seem to be the ideal way, along with allowing the brain to have fluidity again with psychotropic plant medicines seems to be one ideal as well: MDMA for post-traumatic stress therapy, Psilocybin mushrooms (magic mushrooms), and Ayahuasca ceremonies are also powerful tools - that research is beginning to show.

There are also diagnostics possible for our sensory (e.g. through auditory channel) to check for imbalances and sensory processing blocks, which allows for accurately predicting a set of behaviours depending based on the diagnostic - and then sound therapies that exist to help 'unlock' those blocked development processes.

Then there are different levels of modalities of getting the nervous system and energy flowing again, from being more stagnant to completely stagnant - some more 'brute force' methods like acupuncture - Traditional Chinese Medicine methods - to the more subtle energy movement of say Reiki or osteopathy; and without getting into a debate - or arguing that placebo is a powerful benefit on its own - a further level of subtlety - if you believe in them or are sensitive enough and therefore potentially fragile enough to experience benefit from them: homeopathic remedies.

Do you have any references on the sound therapies? Sounds interesting.

Exposure therapy is pretty effective and works by introducing new information, so it can't be too defective. A cat scratched me when I was a kid and I was afraid of cats for a few years, but I met some friendly ones and overcame my fear. I'm guessing the updating is harder for some, especially risk-adverse types (those more sensitive to negative stimuli and less sensitive to reward).

It’s a defect if it causes a person’s brain to have an illogical stress response. For instance, the vast majority of pet dogs are harmless. But, my daughter, who was nipped by a dog when she was a toddler, will probably always be somewhat fearful of dogs (as I am, for the same reasons). Some people have a greater risk for trauma from these types of events. And, while useful at one point, it is now problematic for modern living.

It is not a defect and it is a defect. I mean there is a big reasons behind such a response, but these reasons are often do not justify the severity of a response. Moreover bad memories could become worse with a time passing -- each act of reminding triggers an emotional response which becomes a part of memories.

So it is a valuable mechanism increasing fitness and survivability, but it is not perfect. Especially it is not perfect in a modern environment where there are very little hope to face a mortal danger. I believe it worked better 100k years ago for hunter-gatherers.

I dream sometimes that scientists found a way to fine tune a human mind for a modern environment to increase fitness. How humans would behave after such a tuning? Though it wouldn't work, I'm afraid, because society is obsessive about safety and if people started to behave recklessly, than society would try to create even safer environment for them. A few more iterations of fine tuning and there would be no fear of death at all.

"It is not a defect and it is a defect. I mean there is a big reasons behind such a response, but these reasons are often do not justify the severity of a response."

The issue is that the phrasing, and many peoples' mindset, seems to be that it's a trivial problem and solving it can be taken for granted; we just have to find the right trigger to enable the solution.

Generalizing from specific instances is the root of...well, isn't it the root of basically every intellectual and social problem there is? It's about as likely to have an on-off switch hidden somewhere as world peace.

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