Figure 5.

Mechanical stimulation produces reflection. (A) Schematic diagram of experimental setup. Mechanical stimulation was produced by a glass pipette lowered onto the skin. Impulses arriving at the soma triggered a test electrical stimulus delivered through the same saline-filled pipette. (B) Mechanical stimulation produced a train of impulses. (C) Eight seconds after the onset of the stimulus, the trigger was engaged. The test impulse reached the soma, indicating that no reflection occurred. (D) Twelve seconds after stimulus onset, the trigger was engaged a second time. This time, the test impulse did not reach the soma, showing that the earlier mechanically elicited impulse had reflected. (E) Superimposed recordings of an impulse that reflected, and the first impulse in the train, which did not reflect.