The battery analogy was not one of my favorites- for me, it just left to many questions unanswered. I was looking online and google and I stumbled upon a website (www.mult-sclerosis.org/actionpotential.html) that discusses this topic. It says: "An often used but slightly misleading analogy for how nuerons work is to compare them to electrical wires along which nerve transmissions flow. THis is not actually how they work. A better analogy is to imagine a skipping rope lying on the group. If you take hold of one end of the rope adn give it a quick vertical flick, a wave will move along the rope away from your hand. Nothing except energy actually moves down the rope and, whtn the wave has finished, the rope is in the same position it was before you sent the energy along it". To me, this jump roping analogy is more along the lines of what I imagined the nueron transmission actually occured. I have always thought it was a quick impulse and then the activity returned to its original state- I am not saying that I am not open to new ideas about how it actually works, I have always just thought this was so. For the myelin sheath, I tend to think of this has a wire casing. On thick wires, like our internet cords, the rubber that holds them all together is what I tend to think of the myelin sheath. It holds the impulse together and contains materials that foster the ability to send the impulse quickly and without it, the message could be lost along the way.