Results

The ANOVA on CRs revealed that participants performed more accurately when information was presented after a standard S1 (CRs = 91.7, SD = 5.88) than after a deviant S1 (CRs = 88.3, SD = 9.13), F(1, 9) = 12.540, p < .01. Moreover, the shorter the ISI, the larger the difference between the responses occurring after standard or deviant S1, as revealed by the ISI by stimulus S1 type interaction, F(2, 18) = 19.332, p < .0001. This interaction is illustrated in Figure 3. Contrast analyses revealed that the response accuracy was greater after a standard S1 than after a deviant S1 only for the shorter ISI, ISI 100, F(1, 18) = 54.01, p < .0001; ISI 150, F(1, 18) = 2.58, p > .05; ISI 200, F(1, 18) = 1.94, p > .05.

The ANOVAs performed on RTs revealed that participants responded faster when information was presented after a standard S1 (RTs = 687 ms, SD = 96.01) than after a deviant S1 (RTs = 721 ms, SD = 108.25), F(1, 9) = 38.046, p < .001. Moreover, the shorter the ISI, the longer the RTs, F(2, 18) = 60.474, p < .0001. However, the effect of stimulus S1 type varied with the ISI, F(2, 18) = 5.550, p < .02. This result is illustrated in Figure 4. In this figure, we can see that the differences between the RTs after a standard or a deviant S1 seem smaller for the longer ISI, that was confirmed by contrast analyses: ISI 100, F(1, 18) = 25.85, p < .0001; ISI 150, F(1, 18) = 44.67, p < .0001; ISI 200, F(1, 18) = 4.18, p = .056.