Fig.1 Controllable regions of (a) spiral wave and (b) spatiotemporal chaos in the n-Vc parameter plane (□ and the points above □ are controllable points that have not been confirmed by numerical simulation. The area above the solid curve is controllable area and the rest is uncontrollable area. The area above the dotted line in (a) is controllable area (Ⅰ) in which spiral wave can be controlled quickly. The other is controllable area (Ⅱ) in which spiral wave cannot be controlled quickly.)

Fig.2 Control time distribution of (a) spiral wave and (b) spatiotemporal chaos in the n-Vc plane

Fig.3 Evolution of the mean membrane potential difference at ${\bar G}$si= 0.02 mS ·cm-2 (a) Vc=-78 mV, n= 9; (b) Vc=-73.5 mV, n= 9; (c) Vc=-73.5 mV, n= 10; (d) Vc= -65 mV, n= 15; (e) Vc= -65 mV, n= 16; (f) Vc= -62.5 mV, n= 16; (g) Vc= -62.5 mV, n= 25; (h)Vc= -59 mV, n= 16; (i) Vc= -59 mV, n= 25

Fig.4 Patterns of membrane potential at different moments for ${\bar G}$si= 0.02 mS ·cm-2, Vc = -73 mV and n = 10 (a) t = 4 ms; (b) t = 20 ms; (c) t = 48 ms; (d) t = 104 ms

Fig.5 Local blowup of patterns shown in Fig. 4

Fig.6 Patterns of membrane potential at different moments for ${\bar G}$si= 0.02 mS ·cm-2, Vc= -60 mV and n= 16 (a) t= 4 ms; (b) t= 40 ms; (c) t= 248 ms; (d) t= 456 ms; (e) t= 712 ms; (f) t= 1 180 ms; (g) t= 1 560 ms; (h) t= 1 660 ms; (i)t= 1 760 ms

Fig.7 Trajectories of spiral wave tip at G si= 0.02 mS ·cm-2 (a) Vc= -60 mV, n = 16; (b) Vc= -73 mV, n = 10

Fig.8 Evolution of the mean membrane potential difference at ${\bar G}$si= 0.05 mS ·cm-2 (a) Vc= -72.5 mV, n = 10; (b) Vc= -72.5 mV, n = 20; (c) Vc= -63 mV, n = 20

Fig.9 Patterns of membrane potential at different moments for ${\bar G}$si= 0.05 mS ·cm-2, Vc= -66.5 mV and n = 12 (a) t = 0 ms; (b) t = 20 ms; (c) t = 40 ms; (d) t = 140 ms; (e) t = 440 ms; (f) t = 800 ms; (g) t = 1 340 ms; (h) t = 1 580 ms; (i) t = 1 700 ms