Expecting the unexpected: Violation of expectation shifts strategies toward information exploration

As our environment is frequently changing, it is common that our expectations are violated by unexpected stimuli or events, which leaves us uncertain about which pieces of information will be useful in the future. It is unclear how an expectation violation affects the subsequent control settings for processing of information. The current study directly addressed this issue by employing a double-surprise-trial paradigm based on the attribute amnesia task (Chen & Wyble, 2015a). In Experiment 1, participants were asked to report the location of a target letter presented among distractor digits on several trials and were then unexpectedly asked to report a different attribute (color or identity) of the target letter. In the next trial, participants were asked another unexpected question about the other attribute (identity or color respectively). The results show that, despite participants' poor performance in the first surprise trial, which replicated the attribute amnesia effect, their memory performance in the second surprise trial was dramatically improved, even when the probed attribute was different from that of the first surprise trial. This was also true in Experiment 2, where 15 trials were inserted between the two surprise trials. Experiment 3 further clarified that this effect is not triggered by the mere presence of a surprise test, but rather the violation of expectation about the nature of a surprise test. These results suggest the operation of an adaptive control mechanism that reduces the selectivity of processing in the face of unexpected events.