Before revision:  the enhancement occurred in the vicinity of the bifurcation on limit cycle. The optimal period ratio in the smooth oscillator for the enhanced trainability coincided with the experimentally observed ratio, which suggested the biological exploitation of the period mismatch.
After revision:  the enhancement occurred in the vicinity of the bifurcation on their limit cycles. In the smooth oscillator for the enhanced trainability coincided with the experimentally observed ratio, which suggested the biological exploitation of the period mismatch.