Hysteresis loop. Mean angular velocity $\langle \omega \rangle$ under external torque, which is averaged over time and independent runs of both positive and negative rotations, considering the positive and negative signs. Simulations of the blue curve start from random initial conditions, while those of the black and red curves start from the URS at $M_{\text{e}}=1500$ and $M_{\text{e}}=-1500$, respectively. The hollow symbols means that both positive and negative rotations are observed, while the solid symbols indicate that only positive or negative rotations occur ($F_{\text{a}}=8$, $D_{\text{r}}=0.001$ and $\varphi =0.15$).