David P. C. Lloyd

The transmission of impulses through the inferior mesenteric ganglia

THE transmission of impulses through ganglia of the autonomic nervous system and the physiology of ganglion cells have been studied by Bishop & Heinbecker [1932], Eccles [1935a, b, c, d, 1936a, b, c], Obrador & Odoriz [1936] and Whitteridge [1937]. Theiinferior mesenteric ganglia, with several preganglionic nerves and situated, as they are, so closely together with commissural connexions uniting them, offer unusual possibilities for investigation by the technique described by Eccles [1935a]. The conditions of transmission through these ganglia were in part elucidated by Langley & Anderson [1895] using the motor activity of the bladder and other pelvic viscera as indicators. A preliminary account of some of the present work has been published [Lloyd, 1937].

Centripetal Discharges in Dorsal and Ventral Roots Following Stimulation of Muscle by Ventral Root Volleys

Conclusion The latency of the discharges under consideration, their parallelism with muscle action in the normal and curarized preparations, and the fact that they occur in fibers other than those carrying the centrifugal motor volley, point to the synchronously active muscle as the causal agent. The suggestion may be advanced that the action potential of the excited muscle is capable of stimulating intramuscular motor and sensory nerve endings.