THE ANALYSIS OF INDIVIDUAL WAVES IN THE PHRENIC ELECTRONEUROGRAM

Abstract

In the action potentials of the phrenic nerve of the dog, as recorded during an inspiration with the cathode ray oscillograph, the individual volleys are often seen to be separated by complete pauses. The volleys have a duration 3-7 times as long as the potential in a single fiber. When the area of the largest volleys is compared with that of the maximum action potential produced by artificial stimulation, it is seen that the volley areas are never larger than the portion of the artificial wave attributable to motor fibers. Approximately all the motor fibers may be occupied in a large volley but in most volleys the number of active fibers is well below maximum. There is therefore no reason to assume repetition in a single axon during one volley.