Mean percentage of eyeblink conditioned responses (CRs) made on CS trials and on No-CS (control) trials over the five blocks of 20 trials. Each block of 20 trials included exactly 10 conditioning trials, five blank trials, and five US-alone trials. The three different trial types were presented in random order, except for the restrictions that there could be no more than three conditioning trials in a row and no more than two blank or US-alone trials in a row. Data are presented separately for participants classified as aware (left panels) and unaware (right panels) of the CS–US contingency by post-experimental questionnaire. Data for participants in the Delay conditioning group are shown in the upper panels and data for participants in the Trace conditioning group are shown in the lower panels.
