Pause, B. M., Jungbluth, C., Adolph, D., Pietrowsky, R. & Dere, E. (2010).
Induction and measurement of episodic memories in healthy adults.
Journal of Neuroscience Methods, 189, 88-96.

Abstract

Episodic memory can be inferred from verbal and behavioral manifestations of the knowledge regarding the content (what happened), place (where did it happen) and temporal context (in terms of the sequence of events attended) of personally experienced events. In this report we describe a novel method to induce de novo episodic memories in humans for unique events in the laboratory and measure them with standardized ratings as well as via non-verbal motor responses. Visual stimuli are hidden in four out of eight quadrants on a computer-screen. Each of these quadrants could be highlighted by pushing a corresponding button on a keyboard and either revealed a visual stimulus for 100 ms or remained black. Participants had to remember on which occasion/encoding episode (when) and at which position (where) a specific picture (what) has been encountered. Healthy adult participants were able to recollect and communicate the details and the spatiotemporal context of visual stimuli with combinations of high or low concreteness and neutral or emotional content after retention delays up to 72 h. The mean number of button presses to each of the four quadrants harbouring visual stimuli during the exploration of the stimuli was positively correlated with verbal episodic memory performance. We conclude that episodic memories can be induced experimentally and measured by exploratory button press behaviour which can serve as a non-verbal behavioral correlate of episodic memory performance.