Neuron Models

After tea, the monks and I dove into neurons.  We looked at some photographs of real neurons and identified the major parts of a neuron (dendrites, cell body, axon and terminals).  We modeled neurons in several ways.  First, I showed them how their hands and arms can be neurons:  fingers = dendrites; hand = cell body; arm = axon; elbow = terminal.  Second, we made neurons from pipe cleaners I brought all the way from Seattle.  Third, they made neurons by pulling yarn through their fingers in a special pattern. 

With two of the pipe cleaner neurons, I showed them how the terminal of one neuron comes very close to a dendrite of another neuron, but they don’t actually touch.  I asked how might one neuron talk to another neuron.  The monks came up with some creative ideas (gravity, movement, waves, electricity), but no one suggested chemicals.   I explained how each neuron is like a small battery that makes a small amount of electricity and that the electricity travels down the axon.  At the terminal, the electricity causes chemical to be released that then attach to special places on a dendrite.

We modeled the electrical and chemical processes of neurotransmission with a 5-foot long string neuron I made the previous day.  Several monks held string dendrites, another held the terminal containing beads as chemical transmitters, and one monk stood a few feet away to represent the dendrite of another cell.  I had a rolled up tube of paper on the axon to represent the action potential (electrical signal).  After I handed “monk dendrites” a few beads, I sent the “action potential” down the axon to cause the “neurotransmitters” to come out at the terminal.  The demonstration worked the first time and all of the monks laughed as the monk tried to catch the falling beads.  

We also played the “pass the neurotransmitter” game where two teams of monks form a chain of neurons.  They pass the neurotransmitter down the line to see which team can send a signal the faster.  I think the monks enjoyed the game and I emphasize that what I really wanted them to remember was that the signal inside a neuron was electrical and the signal between neurons was chemical.  I think they got it…I’ll find out tomorrow when I see what they remember from the lesson.