Expression of botulinum toxin in PCs suppresses active avoidance conditioning. A, B, Turning frequency (turns/min) and swimming speed (mm/s) of Tg(aldoca:BoTxBCL-GFP) (aldoca:BoTx) and control sibling fish during free swimming (aldoca:BoTx; n = 45, control; n = 35). The graph shows the averages and SEs of the data (ns indicates non-significance, Welch’s t test). C, Response to electric shocks in aldoca:BoTx fish (n = 7). Swimming speed was calculated for 2 s before and after the electric shocks (***p < 0.001, Welch’s t test). D, Percentages of active avoidance learners of aldoca:BoTx (n = 45) and control (n = 35) fish (**p < 0.01, Fisher’s exact test). E, Number of trials required to establish active avoidance conditioning (aldoca:BoTx: n = 6; control: n = 16). The graph shows the averages and SEs of the data (ns indicates non-significance, Welch’s t test).