> And thus higher voltages overcome resistance more than lower
> voltages

I'm not sure of the exact physiology, but if you're talking about
a cardiac shock, generally the closer to the heart the potential
difference pathway, the lower the danger voltage. Even down
to 12V is dangerous for the correct current path. A figure of
around 30-50mA through the heart is often quoted, which would
usually be hard to get at 12V, considering body resistance. Not
so hard with a higher PD, like 120VAC or 230VAC

Muscle and nerve cells operate at very low currents, for example
you need only very low-power intra-cranial impulses at brain sites
to cause effects. You'll know how easy it is to get a shock with
contact through wet or mucous tissue, like the battery on the tongue,
whereas it takes a lot more than that for dry skin

If you connected electrodes directly to a heart muscle you wouldn't
need much to swamp its normal operation. Not quite the same as a
defribrilator though, which overwhelms the electrical chaos with a
controlled blast of energy, allowing the heart to recover its natural
rhthym

Joe
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