Strategic retrieval and retrieval orientation in reality monitoring studied by event-related potentials (ERPs).

Reality monitoring requires the differentiation between perceived and imagined events or between our own actions and the actions of others. The role of control processes in reality monitoring is yet not fully understood. In the current event-related potential (ERP) study, we investigated such control processes in the form of retrieval orientation and strategic retrieval of nontarget information. At study, complete or incomplete object words were presented in sentences. Participants had to identify the words as the subject of the sentence (perceive condition) or had to complete them upon presentation of a word fragment (self-generate condition). The participants' memory accuracy was better for generated items than for perceived items, as tested in a subsequent memory exclusion task. Comparison of ERPs to new items between the two test conditions (i.e. assessing retrieval orientation) showed more positive ERPs when generated object names were targeted. Retrieval orientation also modulated the early midfrontal old/new effect: Items of the self-generate condition elicited this effect irrespective of their target/nontarget status, while in response to the less well remembered items of the perceive condition it was only found when these items were defined as targets. Target retrieval (as reflected in the left-parietal old/new effect) occurred in both test conditions, but nontarget retrieval was observed only for generated items (when perceived items were targeted). Current findings indicate that retrieval orientation can modulate familiarity-related processes. The selective occurrence of nontarget retrieval for generated items corroborates the concept that the ease with which nontarget information can be accessed promotes nontarget retrieval.