Fig. 1

The learning ability and spatial memory of the VAD, VAN and VAS groups. a The escape latency of all the groups. b The path length of all the groups. c The passing times of all the groups. d The swimming speed levels between the four groups. e A representative trace of VAD group. f A representative trace of VAN group. g A representative trace of VAS group. h A representative trace of control group. i The active avoidance response rates of the four groups. j The passive avoidance response rates of the four groups. k The none avoidance response rates of the four groups. The data are expressed as the means ± SEM, N = 20, ^aP ≤ 0.05, ^bP ≤ 0.01, ^cP ≤ 0.05, ^dP ≤ 0.01