The most common visualization of an action potential is a graph of the difference in membrane potential (y axis) at a particular time (x axis).
According to my textbook Cognitive Psychology by E. Bruce Goldstein, an action potential sent from neuron down the axon remains the same. That is, if we plot the action potential as described above, then at each as it is propagated down it will have the same shape on the graph (within some range of error obviously, but he is saying the error is trivial). But he then says on page 34
One way to answer the question of how action potentials determine different qualities [(e.g. taste of something sweet)] is to propose that the action potentials for each quality might look different. However, [Edgar] Adrian rules out that possibility by determining that all action potentials have basically the same height and shape.
My Question
Can someone confirm these two facts:
- Once an action potential is sent from a given neuron down the axon, does the shape and amplitude remain constant as it is propagated?
- Do all action potentials have the same amplitude and shape?