Oscillations:
Oscillations
are a useful part of what nervous systems do. Chewing and walking are two examples
of rhythmic motor patterns that are a part of many organisms.
Oscillating Networks With a Pace-Maker Cell:
One way that a collection of neurons can oscillate is to have one of the neurons
oscillate on its own, and have the other cells oscillate because they are told
to do so (through their synaptic interactions) by the neuron that intrinsically
oscillates. In this situation, we call the intrinsically oscillating neuron
the "pace-maker" since it sets the pace for the entire network. But this isn't
the only way to have a network that oscillates. Just as a single oscillating
neuron can contain a collection of currents that don't oscillate on their own,
but when they get together they start to oscillate, a network of neurons can
contain only neurons that don't oscillate on their own, but when they get together
they do. This is an example of an emergent property. Sometimes emergent properties
are seen as spooky, imprecise things (until you've looked at them for a long
time and gotten tired of feeling spooked out), and without mathematics, they
are imprecise things. With mathematics, they can be made precise, but they're
still a little spooky.
How Do Neurons That Don't Oscillate Get Together
To Oscillate? When is the whole greater than the sum of its parts...?
What makes the system oscillate?
It wouldn't be completely honest to say that you can't get some understanding of these questions without completely understanding the mathematics involved, but by understanding the mathematics, you can gain a deeper, more reliable understanding. After all, mathematics is just the process of making your understandings of the relationships between things more precise and self-consistent.
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References:
Kandel, E., Schwartz J., and Jessel, T., (eds.) "Principles of Neural Science.
Third Edition," New York: Elsevier, 1991.