Embryonic oscillators with frequency memory

Embryonic oscillators with frequency memory

Experiments reveal vertebrate embryonic oscillators can actively change internal frequency to adapt to external signals over time. This suggests a new 'unclocklike' behavior, inconsistent with standard limit cycle models. Simple models are proposed where a phase oscillator activates a memory variable controlling the oscillator's frequency. Two coupling variations are studied. These models recapitulate intriguing properties seen experimentally like broad entrainment ranges and plateauing entrainment phase with detuning. New phenomena are also predicted like hysteresis, bistability in frequency, and probabilistic entrainment.