Synaptic summation is the technical term used in neurophysiology for those instances in which some neuron C is fired only by a combination of neurons A and B.
My grandfather played a mandolin, so I got my hands on that. Then on down to a banjo, and I found I couldn't play any kind of soft or mournful music with that so I took up the fiddle in my late 20s or early 30s - and that was far too late. But it keeps me off the streets. It has been a love of mine
I don't judge anybody because I've been the one to party and look for the after party to begin! I have more fun now both when I DJ and in general.