title: How low can you go? Changing the resolution of novel complex objects in visual working memory according to task demands.
abstract: In three experiments we manipulated the resolution of novel complex objects in visual working memory (WM) by changing task demands. Previous studies that investigated the trade-off between quantity and resolution in visual WM yielded mixed results for simple familiar stimuli. We used the contralateral delay activity as an electrophysiological marker to directly track the deployment of visual WM resources while participants preformed a change-detection task. Across three experiments we presented the same novel complex items but changed the task demands. In Experiment 1 we induced a medium resolution task by using change trials in which a random polygon changed to a different type of polygon and replicated previous findings showing that novel complex objects are represented with higher resolution relative to simple familiar objects. In Experiment 2 we induced a low resolution task that required distinguishing between polygons and other types of stimulus categories, but we failed in finding a corresponding decrease in the resolution of the represented item. Finally, in Experiment 3 we induced a high resolution task that required discriminating between highly similar polygons with somewhat different contours. This time, we observed an increase in the item's resolution. Our findings indicate that the resolution for novel complex objects can be increased but not decreased according to task demands, suggesting that minimal resolution is required in order to maintain these items in visual WM. These findings support studies claiming that capacity and resolution in visual WM reflect different mechanisms.
authors.affiliation: The School of Psychological Sciences, Tel-Aviv University Tel-Aviv, Israel.
authors.forename: Ayala S
authors.initials: AS
authors.lastname: Allon
authors.affiliation: The School of Psychological Sciences, Tel-Aviv University Tel-Aviv, Israel.
authors.forename: Halely
authors.initials: H
authors.lastname: Balaban
authors.affiliation: The School of Psychological Sciences, Tel-Aviv University Tel-Aviv, Israel ; The Sagol School of Neuroscience, Tel-Aviv University Tel-Aviv, Israel.
authors.forename: Roy
authors.initials: R
authors.lastname: Luria
keywords: capacity; contralateral delayed activity; electrophysiology; resolution; visual working memory
references.citation: Trends Cogn Sci. 2013 Aug;17(8):391-400
references.pmid: 23850263
references.citation: Biol Psychol. 2011 May;87(2):296-302
references.pmid: 21501654
references.citation: Proc Natl Acad Sci U S A. 2011 Jul 5;108(27):11252-5
references.pmid: 21690375
references.citation: J Neurosci. 2011 Jan 19;31(3):1128-38
references.pmid: 21248137
references.citation: Psychol Aging. 2013 Mar;28(1):77-86
references.pmid: 23066799
references.citation: Nature. 1997 Nov 20;390(6657):279-81
references.pmid: 9384378
references.citation: Nature. 2006 Mar 2;440(7080):91-5
references.pmid: 16382240
references.citation: PLoS One. 2013;8(2):e57913
references.pmid: 23469103
references.citation: Psychol Sci. 2012 Jun;23(6):554-9
references.pmid: 22527526
references.citation: Nature. 2008 May 8;453(7192):233-5
references.pmid: 18385672
references.citation: Behav Res Methods Instrum Comput. 2002 Feb;34(1):55-68
references.pmid: 12060991
references.citation: J Neurosci Methods. 2004 Mar 15;134(1):9-21
references.pmid: 15102499
references.citation: PLoS One. 2012;7(8):e41223
references.pmid: 22905099
references.citation: Psychon Bull Rev. 2010 Oct;17(5):673-9
references.pmid: 21037165
references.citation: J Abnorm Psychol. 2003 Feb;112(1):61-71
references.pmid: 12653414
references.citation: Neuropsychologia. 2011 Jun;49(7):1943-52
references.pmid: 21435348
references.citation: Psychon Bull Rev. 1994 Dec;1(4):476-90
references.pmid: 24203555
references.citation: Psychol Sci. 2011 Nov;22(11):1434-41
references.pmid: 21987693
references.citation: Science. 2008 Aug 8;321(5890):851-4
references.pmid: 18687968
references.citation: J Vis. 2009 Jul 31;9(7):17
references.pmid: 19761332
references.citation: Psychol Sci. 2004 Feb;15(2):106-11
references.pmid: 14738517
references.citation: J Exp Psychol Gen. 2004 Sep;133(3):355-81
references.pmid: 15355144
references.citation: Brain. 2010 Sep;133(9):2702-13
references.pmid: 20624814
references.citation: Cortex. 2007 Jan;43(1):77-94
references.pmid: 17334209
references.citation: Neuropsychologia. 2011 May;49(6):1458-65
references.pmid: 21335015
references.citation: Nature. 2004 Apr 15;428(6984):748-51
references.pmid: 15085132
references.citation: Cogn Psychol. 2005 Aug;51(1):42-100
references.pmid: 16039935
references.citation: Psychol Sci. 2007 Jul;18(7):622-8
references.pmid: 17614871
references.citation: Neuropsychology. 2013 Mar;27(2):220-9
references.pmid: 23527650
references.citation: J Neurol. 2010 Jul;257(7):1160-9
references.pmid: 20162428
references.citation: J Cogn Neurosci. 2010 Mar;22(3):496-512
references.pmid: 19301998
references.citation: J Abnorm Psychol. 2006 Nov;115(4):658-73
references.pmid: 17100524
references.citation: Nature. 2005 Nov 24;438(7067):500-3
references.pmid: 16306992