Here we present a simulation of Ciona’s motor ganglion (MG), which includes the core MG components (MN, MGIN, AMG, ddN), as well as additional cell populations, such as ACIN, PMGN, mt, and BTN. Upon delivering a stimulus to the right ddN, left-side MNs produce a spike, which is consistent with a reorienting tail flick that a larva would perform during the escape behavior. After altering the connectivity of ddNs, so that the ddNs no longer project contralaterally, but ipsilaterally, the motor response becomes perturbed. The simulation recapitulates described in the literature larva’s escape behavior, and represents a starting point for further explorations of MG firing patterns.