Davis Greg, Holmes Amanda
Department of Experimental Psychology, University of Cambridge, Downing Street, Cambridge CB2 3EB, England.
Mem Cognit. 2005 Mar;33(2):185-95. doi: 10.3758/bf03195307.
Luck and Vogel (1997) have reported several striking results in support of the view that visual short-term memory (VSTM) has a fixed capacity of four objects, irrespective of how many relevant features those objects comprise. However, more recent studies have challenged this account, indicating only a weak effect of the number of objects once other factors are more evenly equated across conditions. Here, we employed a symmetry manipulation to verify object segmentation in our displays, to demonstrate that when spatial and masking factors are held constant, the number of objects per se has no effect on VSTM. Instead, VSTM capacity may reflect the number of object "parts" or feature conjunctions in a given display.
