title: Decoding of coherent but not incoherent motion signals in early dorsal visual cortex.
abstract: When several scattered grating elements are arranged in such a way that their directions of motion are consistent with a common path, observers perceive them as belonging to a globally coherent moving object. Here we investigated how this coherence changes the representation of motion signals in human visual cortex using functional magnetic resonance imaging (fMRI) and multivariate voxel pattern decoding, which have the potential to reveal how well a stimulus is encoded in different contexts. Only during globally coherent motion was it possible to reliably distinguish fMRI signals evoked by different directions of motion in early visual cortex. This effect was specific to the retinotopic representation of the visual field quadrant in V1 traversed by the coherent element path and could not simply be attributed to a general increase in signal strength. Decoding was more reliable for cortical areas corresponding to the lower visual field. Because some previous studies observed poorer speed discrimination when motion was grouped, we also conducted behavioural experiments to investigate this with our stimuli, but did not reveal a consistent relationship between coherence and perceived speed. Taken together, these data show that neuronal populations in early visual cortex represent information that could be used for interpreting motion signals as unified objects.
authors.affiliation: UCL Institute of Cognitive Neuroscience, London, UK. s.schwarzkopf@fil.ion.ucl.ac.uk
authors.forename: Dietrich Samuel
authors.initials: DS
authors.lastname: Schwarzkopf
authors.forename: Philipp
authors.initials: P
authors.lastname: Sterzer
authors.forename: Geraint
authors.initials: G
authors.lastname: Rees
mesh_terms: D000328:Adult; D001931:Brain Mapping; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D009039:Motion Perception / Q000502:physiology*; D014793:Visual Cortex / Q000502:physiology*; D055815:Young Adult
references.citation: Percept Psychophys. 2001 Nov;63(8):1314-29
references.pmid: 11800459
references.citation: Science. 1996 Feb 2;271(5249):651-3
references.pmid: 8571128
references.citation: Neuroimage. 2010 Feb 1;49(3):1943-8
references.pmid: 19285144
references.citation: J Vis. 2008 May 19;8(7):2.1-9
references.pmid: 19146235
references.citation: Curr Biol. 2003 Feb 18;13(4):342-9
references.pmid: 12593802
references.citation: J Neurosci. 2010 Jan 6;30(1):325-30
references.pmid: 20053913
references.citation: J Vis. 2008 Mar 28;8(3):31.1-12
references.pmid: 18484837
references.citation: Neuroimage. 2010 Feb 1;49(3):1957-64
references.pmid: 19715765
references.citation: Vision Res. 2006 Apr;46(8-9):1540-6
references.pmid: 16168457
references.citation: J Neurophysiol. 2009 Sep;102(3):1930-44
references.pmid: 19587316
references.citation: Vision Res. 1991;31(9):1619-26
references.pmid: 1949630
references.citation: Vision Res. 1993 May;33(7):993-9
references.pmid: 8506641
references.citation: Vision Res. 2001 Dec;41(27):3775-82
references.pmid: 11712989
references.citation: Nat Neurosci. 2005 May;8(5):686-91
references.pmid: 15852013
references.citation: J Neurosci. 2007 Jan 31;27(5):1015-23
references.pmid: 17267555
references.citation: Neuroimage. 2006 Sep;32(3):1308-16
references.pmid: 16822682
references.citation: Science. 1995 May 12;268(5212):889-93
references.pmid: 7754376
references.citation: Curr Biol. 2006 Jun 6;16(11):1096-102
references.pmid: 16753563
references.citation: J Vis. 2008 Nov 21;8(15):10.1-12
references.pmid: 19146294
references.citation: Neuron. 1992 Jul;9(1):1-13
references.pmid: 1632964
references.citation: Cereb Cortex. 2001 Dec;11(12):1182-90
references.pmid: 11709489
references.citation: J Neurosci. 1997 Mar 15;17(6):2112-27
references.pmid: 9045738
references.citation: J Neurophysiol. 2006 Jun;95(6):3654-64
references.pmid: 16510776
references.citation: J Neurosci. 2003 Apr 1;23(7):2947-60
references.pmid: 12684482
references.citation: Cereb Cortex. 1997 Apr-May;7(3):283-92
references.pmid: 9143447
references.citation: Nat Neurosci. 2005 May;8(5):679-85
references.pmid: 15852014
references.citation: Spat Vis. 2000;13(4):393-401
references.pmid: 11310533
references.citation: Neuroimage. 2003 Aug;19(4):1273-302
references.pmid: 12948688
references.citation: Neuroimage. 2008 Jan 15;39(2):647-60
references.pmid: 17977024
references.citation: Vision Res. 1997 Nov;37(22):3145-61
references.pmid: 9463696
references.citation: Proc Natl Acad Sci U S A. 2002 Nov 12;99(23):15164-9
references.pmid: 12417754
references.citation: Neuroimage. 1999 Feb;9(2):179-94
references.pmid: 9931268
references.citation: Neuroimage. 2010 Feb 1;49(3):1965-76
references.pmid: 19800408
references.citation: J Neurosci. 1996 Nov 1;16(21):6945-64
references.pmid: 8824332
references.citation: J Neurosci. 1989 Jul;9(7):2432-42
references.pmid: 2746337
references.citation: Percept Psychophys. 2001 Nov;63(8):1293-313
references.pmid: 11800458
references.citation: Neuroimage. 2002 May;16(1):217-40
references.pmid: 11969330
references.citation: Curr Opin Neurobiol. 2000 Aug;10(4):438-43
references.pmid: 10981611
references.citation: Nat Neurosci. 2006 Mar;9(3):429-34
references.pmid: 16462737
references.citation: J Neurosci. 2006 Dec 20;26(51):13128-42
references.pmid: 17182764
references.citation: Nature. 1994 Aug 25;370(6491):644-6
references.pmid: 8065449
references.citation: J Neurophysiol. 2000 Oct;84(4):2048-62
references.pmid: 11024097
references.citation: Nature. 1996 May 9;381(6578):161-3
references.pmid: 8610014
references.citation: Neuroimage. 2007 Feb 1;34(3):1199-208
references.pmid: 17169579
references.citation: J Neurosci. 2002 Oct 1;22(19):8633-46
references.pmid: 12351737
references.citation: J Neurosci. 1996 Nov 15;16(22):7376-89
references.pmid: 8929444
references.citation: Vision Res. 1993 Jan;33(2):173-93
references.pmid: 8447091
references.citation: J Neurophysiol. 2009 Sep;102(3):1854-67
references.pmid: 19605615
references.citation: Neuroimage. 2010 Feb 1;49(3):1953-6
references.pmid: 19596071