Fig. 5

Effect of test compounds on the acquisition of avoidance response. Comparison of the crossing times of A control untreated and scopolamine (SCOP)-treated adults and B adults treated with isoxazole (ISOX) and Convolvulus pluricaulis (CP). The solid circles and squares represent the crossing times measured in the three training sessions and one test session, which was conducted 2 h after the training sessions. These crossing times have been expressed as mean ± standard deviation. Three independent experiments were conducted to determine the effects of SCOP, ISOX, and CP on the fishes, and in each of these experiments, at least 3–5 adult fishes were treated with the least toxic concentrations of SCOP (200 µM), ISOX (31.2 mM) and CP (11.4 mg/ml). The fishes were treated with the AChE inhibitor (i.e. ISOX or CP) one hour before treatment with SCOP. *, **, and *** indicate p-value < 0.5, < 0.01 and < 0.001 of two-tailed unpaired t-test for untreated versus test groups (in most cases, unless indicated otherwise) respectively