Memories are not only in the brain, human cell study finds

  Trauma is a fact of life. Veterans and their families deal with the painful aftermath of combat; one in five Americans has been molested; one in four grew up with alcoholics; one in three couples have engaged in physical violence. Dr. Bessel van der Kolk, one of the world’s foremost experts on trauma, has spent over three decades working with survivors. In The Body Keeps the Score, he uses recent scientific advances to show how trauma literally reshapes both body and brain, compromising sufferers’ capacities for pleasure, engagement, self-control, and trust. He explores innovative treatments—from neurofeedback and meditation to sports, drama, and yoga—that offer new paths to recovery by activating the brain’s natural neuroplasticity. Based on Dr. van der Kolk’s own research and that of other leading specialists, The Body Keeps the Score exposes the tremendous power of our relationships both to hurt and to heal—and offers new hope for reclaiming lives.

[1] https://pmc.ncbi.nlm.nih.gov/articles/PMC8418154/

https://slatestarcodex.com/2019/11/12/book-review-the-body-k...

>As various approaches that can help people with PTSD are suggested by the author, the book would be more comprehensive if further empirical findings are provided to demonstrate their effectiveness and how readers can integrate them into practice

https://pmc.ncbi.nlm.nih.gov/articles/PMC8418154/

https://www.reddit.com/r/ptsd/comments/plskph/warning_the_bo...

https://www.washingtonpost.com/books/2023/08/02/body-keeps-s...

https://bigthink.com/neuropsych/body-keeps-score-trauma/

https://www.newyorker.com/magazine/2022/01/03/the-case-again...

https://forums.studentdoctor.net/threads/analysis-of-the-bod...

A Critical Evaluation of Bessel van der Kolk’s The Body Keeps the Score By Francine Tan

It's literally setup like a gauntlet. New immune cells from marrow come through the Thymus and are tested. They need to pass through and attack foreign cells then pass through and _not_ attack host cells. They are essentially tagged and filtered by this process.

Most cells are let go into the body, some cells are reserved as self regulatory cells, and the others that do not pass are destroyed.

It's a literal quality control and selection machine for your immune system.

However this specifically works in humans — and considering the diversity of actual human preferences includes, amongst many other things, non-existant dragons* — the first I heard of the term "superstimulus" was with the example of certain beetles that kept trying to copulate with beer bottles:

https://en.wikipedia.org/wiki/Supernormal_stimulus

* Humans must have something guiding us, or we'd all be (a) bisexual and (b) equally often aroused by dragons as by those we could actually have a child with; the fact that dragons happen at all is simply an indication that our brains are likely using a very simple set of heuristics to get there, and simple heuristics is totally a thing that DNA could encode

https://aeon.co/essays/how-fetuses-learn-to-talk-while-theyr...

Parental teaching and learning is a spectrum and not a binary. We've found with relocating deer (to similar but not identical environments) doing worse until learning occurs over a few generations and they catch up. Animals may not be as intelligent as us but their ability to learn and adapt should not be underestimated.

How do you know they "know" them?

> all of these things can be encoded as chemical signalling

Why do you presume they are chemical signals?

> pattern matching

Psychedelics show the absurd power of layered pattern matching in our brains and what happens when you disrupt those mechanisms. I would not discount it so readily.

McConnell, J. (1962). Memory transfer via cannibalism in planaria. Journal of Neuropsychiatry, 3, 1-42.

Information that might be passed from parent to offspring after conception is not hereditary by definition, and would be a type of learning, (ie birds singing to babies in eggs, antibody transferring from mother to baby)

Everything else you mention is very easily passed down via genetics which is not chemical signaling, but actual information encoding. And simple rules can lead to complex behavior.

Edit: Here’s an example to better illustrate the genes power of information encoding. Camouflage, which is a genetically heritable trait, can be incredibly complex. We can think of the information encoded in the genes for camouflage as a visual description of the environment that the animal evolved in. So the gene’s have actually encoded what the dessert environment looks like, or the sea floor, or the vegetation. That’s a single example, but every animal carries such complex information (how to navigate certain landscapes, how to survive current living pathogens in the environment, etc) within their genes.

Probably already aware of methods like:

- Tissue Nanotransfection : https://en.wikipedia.org/wiki/Tissue_nanotransfection

- "Direct neuronal reprogramming by temporal identity factors" (2023) https://www.pnas.org/doi/10.1073/pnas.2122168120#abstract

... https://news.ycombinator.com/item?id=36912925

Wild. Doesn't necessarily surprise me too much that the body stores some memories outside the brain, but it seems _very_ surprising that another body/brain can read and understand ones created by another. I'd assume that the whole mind and memory system is one big correlated mess, not essentially composed of data files in a ~standard encoding.

So, for example, a dangerous situation causes stress and stress causes the heart to beat faster, all normal. But make the heart beat faster through external means and it will also cause stress. So it is not clear which one is the cause and which one is the effect, probably some weird combination, with all sorts of feedbacks. Life is messy.

So get a heart that isn't yours and it will not beat in a familiar way, which, in turn may be interpreted as changing emotions. And even if memories are entirely contained within the brain, what if the heartbeat is part of these memories, with a heart that reacts differently, the meaning of these memories may change.

For a tech analogy, in order to record a video game session, it is common to only record player input. If the game is deterministic, you just need to run the game with the recorded inputs and the session will be faithfully reproduced. It is much more compact than something like a video. Now imagine we change the game engine so that it responds slightly differently to inputs, now, when replayed, the game will appear different. If we imagine memories are "replays" and the engine is our body, than altering our body will also alter our memories.

(We tend to think of just the latter, but all three significantly impact “strength”.)

Each of these has mechanisms of maintenance and faster recovery after use lapses. Which can all be described as memory.

First, the spinal cord and motor cortex learn more effective coordination. Proper coordination of muscles impacts strength by ensuring our different muscles cooperate effectively to apply force where we need it. We imagine simple movements as simple efforts, but they are really a series of coordinated multiple muscle response.

This can be considered “normal” neural/cognitive learning and memory in the brain, spinal coord and nervous system.

Second, our nervous system learns to send higher intensity demand signals to the muscles.

I don’t know what the mechanism is here. Maybe higher coordination of simultaneous signals within the muscle? Maybe an increase in signal strengths? An increase in nerve cells? A combination? In any case, once learned, this learning is mostly maintained despite loss of stimulus and relearned quickly.

This creates a common source of injury. After a workout hiatus, our ability to demand intense muscle response can exceed the abilities of our reduced muscle’s capabilities. It can feel too easy to push our bodies hard again, resulting in injuries that abort the attempt to restart training.

Restart weight lifting programs with patience and caution, until muscles catch up with the renewed overload, hypertrophy and recovery cycle.

The third very long term memory mechanism in muscle cells is quite interesting: myonuclear accretion. Support cells merge with muscle cells permanently giving them multiple nuclei, permanently increasing their ability and speed to create the proteins we need for hypertrophy (muscle growth) and recovery (repair and energy store recuperation).

Myonuclear accretion allows muscle cells to grow far beyond their original limits. And accounts for why previously trained muscles can retain a modestly higher level of strength and size, even after training regimen lapses.

All three memory mechanisms account for why regaining previous high levels of strength happens faster, with less effort, than it took to gain any level of strength the first time.

Aother memory mechanism include higher interoception, prioperception, kinematics, and higher level learning regarding exercise form, workout discipline, workout organization, body limitations, injury warnings, positive associations with making effort, etc. that are all result in long term increased strength and ability recover and accumulate it.