Figure 3.

Startle amplitudes to the visual stimuli during the test phase. Bars (with standard errors) depict the startle amplitude in z scores in response to the _FORWARDCS+ (light gray), the _BACKWARDCS+ (black), the CS− (white), and the NEW (striped). Startle responses did not differ among CSs after conditioning in Study 1 (A). On the contrary, startle response was significantly attenuated (i.e., reward-like conditioned responses) by the _BACKWARDCS+ as compared to the _FORWARDCS+ and the NEW after conditioning in Study 2 (B) (^*p < 0.05; ^**p < 0.01).