I did find the idea (from @mh_lab) that some individual *synapses* may be innate and others learned confusing. Does that refer to the existence of the connection or its weight?
It seems more likely that you have genomic rules specifying broadly which cell types connect to which other types, and how, but that all such synapses are then subject to some kind(s) of plasticity
The idea that you could point to some synapses as there due to learning then doesn't make so much sense to me...
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In my view, polygenic scores are a statistical tool, not one with adequate precision in individuals to warrant use in embryo selection.
It is true that those in the very highest PGS deciles for some complex diseases have significantly higher risk than the population average. But any such embryos will also have sibling embryos with higher than average PGS...
How Mathematical ‘Hocus-Pocus’ Saved Particle Physics quantamagazine.org/how-renormaliz… - on the "renormalization group" as a means of traversing scales...
Question: is renormalization just a handy mathematical tool to enable calculations to be done at higher scales (by truncating sums that tend towards infinity OR= averaging over small-scale parameters at some grid size)?
Or is this how nature itself works? Is there real coarse-graining across levels that grants a degree of genuinely level-specific causality? (Contra reductionism) cc @C4COMPUTATION
I mean, these could be very reliable findings. But they rest on some major assumptions: 1. that psychopathy is at the level of brain a single thing. 2. that the analyses included in the met-analysis are not biased at all...
...and 3. that the size of different brain regions is relatable to (and explains differences in) complex psychological functions like moral reasoning
How a ‘fatally, tragically flawed’ paradigm has derailed the science of obesity statnews.com/2021/09/13/how… - is obesity due to over-eating or dysregulated fat storage? cc @StephenORahilly
One point not commented on in article is that genes implicated in obesity (through rare or common variants) are enriched for nervous system expression and function...
Do these regulate appetite (many clearly do) or brain mechanisms controlling fat metabolism? Or both?
Kathryn Paige Harden: ‘Studies have found genetic variants that correlate with going further in school’ theguardian.com/science/2021/s… - tricky stuff here...
It should be no surprise to anyone that children differ in ways that affect (not determine, but contribute to) how far they go in education.
Some of those differences are genetic in origin, others may be the result of variation in brain development (explaining why even identical twins may differ)