title: The efficiency of encoding: limits of information transfer into memory.
abstract: We investigated how visual information is best presented to maximize the number of remembered items in a fixed time unit. In a memory task for images depicting real-world objects, we varied the number of images shown simultaneously, the presentation time, and the interstimulus interval (ISI). The viewing phase was followed by a two-alternative forced choice recognition task. We converted the percentage of correct answers into a capacity estimate scaled to a fixed time unit of 1 s to allow for comparisons across conditions. Our results showed that (1) presenting one image very briefly was always more efficient than simultaneously showing multiple images for longer periods; (2) for single images, the maximum encoding rate was fairly constant over a wide range of conditions, at 1.4 objects per second; (3) when testing was done a week later, memory capacity was the same for all conditions, irrespective of the presentation time and ISI at the initial viewing; (4) highly similar distractors led to worse performance than random distractors; and (5) showing an image twice for 100 ms was associated with worse performance than showing the image once, but for 200 ms.
authors.affiliation: Psychologie und Sportwissenschaft, Abteilung Allgemeine Psychologie, Fachbereich 06, Justus-Liebig-Universität Gießen, Otto-Behaghel-Strasse 10F, 35394, Giessen, Germany. gesche.huebner@gmail.com
authors.forename: Gesche M
authors.initials: GM
authors.lastname: Huebner
authors.forename: Karl R
authors.initials: KR
authors.lastname: Gegenfurtner
mesh_terms: D000328:Adult; D001288:Attention; D002755:Choice Behavior; D004526:Efficiency; D056344:Executive Function; D005260:Female; D006801:Humans; D008297:Male; D009949:Orientation; D010364:Pattern Recognition, Visual; D011930:Reaction Time; D012153:Retention, Psychology; D055815:Young Adult