What if stressful existance pushes for shorter lifespan with the effect of quickening the turnover of generations.

So stressful environment would speed up the evolutionary iteration of generations. While less stressful existance that has adopted to the environment would persist longer.

This analogy happens in some animals for sure. At the zoo they place the antelope near the cheetahs so that they breed more.

And having everything firing at once is a seizure. But somewhere between that and normal is unclear.

It's also possible the association is in the other direction - people with neurons that fire less might be less stressed in general (almost by definition), and maybe the effect of stress on longevity takes place elsewhere entirely.