Table 4. Design summary of Experiment 4.
| Group | Conditioning | Extinction | Surrogate Training | Test | Pred ECH |
|---|---|---|---|---|---|
| NoExt 5 | AX → S (8) | Short Ctx (20 min) | S → US (4) | X | cr |
| NoExt 125 | AX → S (8) | Short Ctx (20 min) | S → US (4) | X | CR |
| ExtA+C 5 | AX → S (8) | A- (200) in long ctx (8 h) | S → US (4) | X | CR |
| ExtA+C 125 | AX → S (8) | A- (200) in long ctx (8 h) | S → US (4) | X | CR |
| ExtC 5 | AX → S (8) | Long Ctx (8 h) | S → US (4) | X | cr |
| ExtC 125 | AX → S (8) | Long Ctx (8 h) | S → US (4) | X | cr |
Note: NoExt = No extinction treatment, ExtA+C = Extinction of A and the context, ExtC = Extinction of the context, 5 and 125 = 5-s and 125-s CS duration, A (tone) = overshadowing stimulus, X (clicks) = target cue, S (white noise) = surrogate outcome, US = footshock. Numbers in parentheses refer to the number of each trial type or duration of context exposure. Pred ECH = predictions of the extended comparator hypothesis (Denniston et al., 2001). CR and cr denote strong and weak stimulus control, respectively.