Coupling between fast and slow oscillator circuits in Cancer borealis is temperature compensated

Coupled oscillatory circuits are ubiquitous in nervous systems. Given that most biological processes are temperature sensitive, it is remarkable that the neuronal circuits of poikilothermic animals can maintain coupling across a wide range of temperatures. Within the stomatogastric ganglion (STG) of the crab Cancer borealis, the fast pyloric rhythm (~1Hz) and the slow gastric mill rhythm (~0.1Hz) are precisely coordinated at ~11°C such that there are an integer number of pyloric cycles per gastric mill cycle (integer coupling). Upon increasing temperature from 7-23°C, both oscillators showed similar temperature-dependent increases in cycle frequency, and integer coupling between the circuits was conserved. Thus, although both rhythms show temperature dependent changes in rhythm frequency, the processes that couple these circuits maintain their coordination over a wide range of temperature. Such robustness to temperature changes could be part of a toolbox of processes that enables neural circuits to maintain function despite global perturbations.