Abstract
Reliance on remembered facts or events requires memory for their sources, that is, the contexts in which those facts or events were embedded. Understanding of source retrieval has been stymied by the fact that uncontrolled fluctuations of attention during encoding can cloud important distinctions between competing theoretical accounts. To clarify the issue, we combined electrophysiology (high-density EEG recordings) with computational modeling of behavioral results. We manipulated subjects’ attention to an auditory attribute, whether the source of individual study words was a male or female speaker. Posterior alpha band (8–14 Hz) power in subjects’ EEG increased after a cue to ignore the gender of the person who was about to speak. Receiver-operating characteristic (ROC) analysis validated our interpretation of oscillatory dynamics. With attention under experimental control, computational modeling showed unequivocally that memory for source (male or female speaker) reflected a continuous, signal detection process rather than a threshold recollection process.
