Visual short-term memory: A methodological caveat.

Reports that estimates of decay time for nonverbal short-term visual memory varied from less than 3 sec to beyond 30 sec in a same-different matching task with 10 male right-handed undergraduates, depending on the physical similarity between target and comparison stimuli. The more dissimilar the stimuli, the higher the memory score at all delays and the slower the decline in performance over time. Findings draw attention to the obvious but commonly neglected point that generalizations concerning the duration of visual short-term memory, particularly as measured by recognition tests, should be routinely based on a psychophysical approach in which various task conditions are systematically varied along with retention interval. Incidental to the main point, results also suggest that decay functions may reflect a decline in accessibility rather than a complete loss of availability of memory traces. (French summary) (27 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)