title: Apparent motion can impair and enhance target visibility: the role of shape in predicting and postdicting object continuity.
abstract: Some previous studies have reported that the visibility of a target in the path of an apparent motion sequence is impaired; other studies have reported that it is facilitated. Here we test whether the relation of shape similarity between the inducing and target stimuli has an influence on visibility. Reasoning from a theoretical framework in which there are both predictive and postdictive influences on shape perception, we report experiments involving three-frame apparent motion sequences. In these experiments, we systematically varied the congruence between target shapes and contextual shapes (preceding and following). Experiment 1 established the baseline visibility of the target, when it was presented in isolation and when it was preceded or followed by a single contextual shape. This set the stage for Experiment 2, where the shape congruence between the target and both contextual shapes was varied orthogonally. The results showed a remarkable degree of synergy between predictive and postdictive influences, allowing a backward-masked shape that was almost invisible when presented in isolation to be discriminated with a d' of 2 when either of the contextual shapes are congruent. In Experiment 3 participants performed a shape-feature detection task with the same stimuli, with the results indicating that the predictive and postdictive effects were now absent. This finding confirms that shape congruence effects on visibility are specific to shape perception and are not due to either general alerting effects for objects in the path of a motion signal nor to low-level perceptual filling-in.
authors: Department of Psychology, University of British Columbia Vancouver, BC, Canada.
authors: Peter J
authors: PJ
authors: Lenkic
authors: James T
authors: JT
authors: Enns
keywords: apparent motion; postdiction; prediction; shape perception; visual masking
references: Vision Res. 2007 Dec;47(28):3424-33
references: 18053847
references: Science. 2000 Mar 17;287(5460):2036-8
references: 10720334
references: Vision Res. 2012 Apr 15;59:25-33
references: 22406661
references: Perception. 2009;38(1):5-16
references: 19323132
references: Vision Res. 1985;25(2):283-8
references: 4013094
references: Exp Brain Res. 1988;70(1):90-8
references: 3402571
references: Percept Psychophys. 1984 Jan;35(1):69-84
references: 6324063
references: Neuroreport. 2005 Apr 4;16(5):491-4
references: 15770157
references: Vision Res. 1976;16(4):329-35
references: 941407
references: J Exp Psychol Hum Percept Perform. 2003 Feb;29(1):106-20
references: 12669751
references: Psychon Bull Rev. 2002 Sep;9(3):489-96
references: 12412888
references: Percept Psychophys. 2000 Nov;62(8):1572-95
references: 11140180
references: J Cogn Neurosci. 2007 Sep;19(9):1488-97
references: 17714010
references: Sci Am. 1986 Jun;254(6):102-9
references: 3704621
references: Neuroimage. 2004 Apr;21(4):1772-80
references: 15050597
references: J Vis. 2006 Sep 22;6(10):1079-86
references: 17132079
references: Neuroimage. 2006 Sep;32(3):1308-16
references: 16822682
references: Vision Res. 2007 Jun;47(12):1624-30
references: 17451777
references: Curr Biol. 2011 May 10;21(9):740-5
references: 21514158
references: Vision Res. 2000;40(2):201-15
references: 10793897
references: Cereb Cortex. 1991 Jan-Feb;1(1):1-47
references: 1822724
references: J Exp Psychol Hum Percept Perform. 2005 Dec;31(6):1171-1180
references: 16366782
references: Vision Res. 2008 Mar;48(7):872-81
references: 18279906
references: J Vis. 2012 Jul 30;12(7):
references: 22847807
references: J Exp Psychol Gen. 2000 Dec;129(4):481-507
references: 11142864
references: Nature. 1994 Jul 28;370(6487):256-7
references: 8035873
references: Nat Neurosci. 1998 Oct;1(6):508-12
references: 10196549
references: J Exp Psychol Hum Percept Perform. 2007 Dec;33(6):1495-503
references: 18085959
references: Cognition. 2010 Apr;115(1):186-91
references: 20035933
references: PLoS Biol. 2005 Aug;3(8):e265
references: 16018720
references: J Exp Psychol Hum Percept Perform. 2006 Dec;32(6):1422-35
references: 17154782
references: J Vis. 2011 Sep 07;11(10):
references: 21900370
references: J Exp Psychol. 1971 Jan;87(1):99-108
references: 5541564
references: Vision Res. 1963 May-Jun;61:191-206
references: 14168288
references: Curr Biol. 2003 Jun 17;13(12):1038-41
references: 12814549
references: Trends Cogn Sci. 2008 Sep;12(9):327-33
references: 18684660
references: J Vis. 2010 Nov 24;10(13):15
references: 21106680
references: Trends Cogn Sci. 2000 Sep;4(9):345-352
references: 10962616