Mean expectancy ratings over de acquisition phase and generalization of acquisition test.

<p>Ratings were registered at the moment the stimulus and expectancy scale disappeared from the screen. Higher levels indicate more certainty about shock (100 = “Certainly a shock”), lower levels indicate more certainty about absence of shock (0 = “Certainly no shock”). The left panel represents the data from the acquisition phase, per trial, for both the CS+ (B1) and the CS- (B2). The right panel shows the data from the generalization of acquisition test of all stimuli from both categories. Each stimulus was presented once during this phase.