I'm not trying to be snarky (in case it sounds like it): But I thought that was the obvious part? Brains are made of neurons and (I thought) neurons produce bi

I'm not trying to be snarky (in case it sounds like it): But I thought that was the obvious part? Brains are made of neurons and (I thought) neurons produce biproducts that have to be "cleaned up" or they slow down/stop working. Isn't that also why (or one possible reason they think why) people with Alzheimer lose their brains? That it was somehow related to the brain's neuron "clean up" helpers that stop working or die off. Then again, the less obvious thing is that the spinal cord has neurons. So I wonder if this comes into play there...