Fig. 8.

Information carried by MnT axons that spanned a blocked ganglion was necessary and sufficient to coordinate swimmeret motor output on opposite sides of a blocked ganglion. These figures show the phases of PS2 bursts relative to PS5 recorded when A3 was blocked and either medial or lateral portions of the connectives between A2 and A3 had been cut bilaterally. A, When the dorsomedial regions that contained the axons of MnT interneurons were spared, normal coordination of PS2 bursts could still be achieved (n = 4 experiments). B, When the dorsomedial regions were selectively cut, sparing the rest of the connectives, stable phase relations of PS2 and PS5 bursts were not observed (n = 5 experiments). The drawings of cross-sections show in each case the regions of the connectives that remained intact (shaded) when the data plotted below were recorded. In each drawing, dorsal is to thetop.