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Alex Holcombe
Polly Barr
• Charlie Ludowici
• Kim Ransley
• Ingrid Van Tongeren
William Ngiam
Fahed Jbarah
• Patrick Goodbourn


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Biphasic Neuron Extrap
A-V flash lag

Following on from [1]

  • The idea of separate position representations (e.g. for first- and second-order motion as suggested by Pavan & Mather 2008) is really fascinating
  • Nicolls,Mattingley,Berberovic,Smith,&Bradshaw(2004) review horiz/vert asymmetries we should check out for ideas
  • To explain the Cai & Schlag smooth pursuit flash mislocalisation effect, Rotman, Brenner , Smeets (2005) suggest that efference copy motion signal is combined with (absent) retinal motion of flash to yield extrapolation. They present their whack-a-mole targets for variable duration and find the longer the exposure duration, the less mislocalization in the direction of the eye movement. They theorize that the reason is that the longer targets have more retinal motion opposite the pursuit, so this cancels the efference copy to eliminate the extrapolation. An alternative account is that longer exposure improves the integration with spatiotopically stationary landmarks, reducing the reliance on the retinotopic code. Since this does not help for targets moving with the eyes, would have to posit that stabilization thanks to landmarks doesn't happen with moving targets. But this seems unlikely. I would like to see 1) Mislocalization when target moves in orthogonal direction 2) Whether variability (presumably spatial in both cases, since we find spatial for Cai&Schlag), which might implicate growth of a spatial code.

Phenomenon Spatial Bias Temporal Bias (increase w/speed beyond thresh) Spatial Variab Temporal Variab Foveo attn effect vectors sum landmarks monotonic inc w/ motion dur n. transient most importnt
Flash-lag some little 0 80ms petal[1],[2] ? yes less spatial σ? yes? yes
Cai .5deg 0[3, 4] ? 0 fugal[5] ??
Hazelhoff,[6] 0 large ?? discrepant Ss[5] ?? ?? ?? ??
Whitney&Cav signif ~0[7],[8] ?? betting0 ?? large ?
Frohlich .5deg fugal:1.5deg,petal:0[9] 0[5],<27ms[10] fugal:10ms,petal:15ms[9],79ms[7]


? 0 fugal[9, 14],0[5] large N/A
onset-repuls <=15ms[15],[16]
repr momentum 33ms[16]
deValois large miniscule miniscule fugal[1] NO
kinetic edge[17] read[18] [18] [18] petal[18]
Motion adapt saturat at 5degpersec/Hz[19] fugal
binding 0[20]
induced motion 0? Yes[21]
timed buttonpress

Temporal variability might arise from:

  1. Position shifting that increases with velocity, with constant noise added to velocity
  2. Uncertainty in *when* the judgment was supposed to be made
  3. For any effects caused by afferent latency (Hazelhoff?), variability in latency

deValois stands out as only temporal bias with spatial variability. Then why doesn't Cai and Frohlich have temporal bias? Only easy explanation would be the possibly-greater blur of the deValois stimuli, so we have to check that. Increasing eccentricity would also increase the spatial uncertainty[22] perhaps allowing temporal to manifest


  1. Linares D and Holcombe AO. Position perception: influence of motion with displacement dissociated from the influence of motion alone. J Neurophysiol. 2008 Nov;100(5):2472-6. DOI:10.1152/jn.90682.2008 | PubMed ID:18753324 | HubMed [LinaresHolcombe2008neurophys]
  2. Kanai R, Sheth BR, and Shimojo S. Stopping the motion and sleuthing the flash-lag effect: spatial uncertainty is the key to perceptual mislocalization. Vision Res. 2004;44(22):2605-19. DOI:10.1016/j.visres.2003.10.028 | PubMed ID:15358076 | HubMed [KanaiShethShimojo04]
  3. Gauch A and Kerzel D. Perceptual asynchronies between color and motion at the onset of motion and along the motion trajectory. Percept Psychophys. 2008 Aug;70(6):1092-103. PubMed ID:18717394 | HubMed [Gauch08]
  4. Linares D, Holcombe AO. Unpublished results. 2008

  5. Hazelhoff FF, Wiersma H. Die Wahrnehmungszeit [The sensation time]. Zeitschrift für Psychologie. 1924;96:171-188

  6. Whitney D, Cavanagh P. (2002) Surrounding motion affects the perceived locations of

    moving stimuli. Visual Cognition 9:139–152.

  7. Whitney D and Cavanagh P. Motion distorts visual space: shifting the perceived position of remote stationary objects. Nat Neurosci. 2000 Sep;3(9):954-9. DOI:10.1038/78878 | PubMed ID:10966628 | HubMed [WhitneyCavanagh00]
  8. Müsseler J and Aschersleben G. Localizing the first position of a moving stimulus: the Fröhlich effect and an attention-shifting explanation. Percept Psychophys. 1998 May;60(4):683-95. PubMed ID:9628999 | HubMed [Musseler98]
  9. Müsseler J and Kerzel D. The trial context determines adjusted localization of stimuli: reconciling the Fröhlich and onset repulsion effects. Vision Res. 2004;44(19):2201-6. DOI:10.1016/j.visres.2004.04.007 | PubMed ID:15208006 | HubMed [MusselerKerzel04]
  10. Kerzel D and Müsseler J. Effects of stimulus material on the Fröhlich illusion. Vision Res. 2002 Jan;42(2):181-9. PubMed ID:11809472 | HubMed [Kerzel02]
  11. Kirschfeld K and Kammer T. The Fröhlich effect: a consequence of the interaction of visual focal attention and metacontrast. Vision Res. 1999 Nov;39(22):3702-9. PubMed ID:10746140 | HubMed [Kirschfeld98]
  12. Müsseler J and Neumann O. Apparent distance reduction with moving stimuli (Tandem Effect): evidence for an attention-shifting model. Psychol Res. 1992;54(4):246-66. PubMed ID:1494610 | HubMed [MusselerNeumann92]
  13. Carbone E and Pomplun M. Motion misperception caused by feedback connections: a neural model simulating the Fröhlich effect. Psychol Res. 2007 Nov;71(6):709-15. DOI:10.1007/s00426-006-0060-8 | PubMed ID:16645880 | HubMed [CarbonePomplun07]
  14. Thornton IM. The onset repulsion effect. Spat Vis. 2002;15(2):219-43. PubMed ID:11991576 | HubMed [Thornton02]
  15. Hubbard TL and Motes MA. Does representational momentum reflect a distortion of the length or the endpoint of a trajectory?. Cognition. 2002 Jan;82(3):B89-99. PubMed ID:11747866 | HubMed [HubbardMotes]
  16. Ramachandran VS and Anstis SM. Illusory displacement of equiluminous kinetic edges. Perception. 1990;19(5):611-6. DOI:10.1068/p190611 | PubMed ID:2102995 | HubMed [RamaAnstis90]
  17. Fan Z and Harris J. Perceived spatial displacement of motion-defined contours in peripheral vision. Vision Res. 2008 Dec;48(28):2793-804. DOI:10.1016/j.visres.2008.09.006 | PubMed ID:18824016 | HubMed [FanHarris08]
  18. Snowden RJ. Shifts in perceived position following adaptation to visual motion. Curr Biol. 1998 Dec 3;8(24):1343-5. PubMed ID:9843685 | HubMed [Snowden98]
  19. Holcombe, A.O. (2009). Temporal binding favors the early phase of color changes, but not of motion changes, yielding the color-motion asynchrony illusion. Visual Cognition- Special issue on binding, 17(1-2), 232-253. doi:10.1080/13506280802340653

  20. Post RB, Chi D, Heckmann T, and Chaderjian M. A reevaluation of the effect of velocity on induced motion. Percept Psychophys. 1989 May;45(5):411-6. PubMed ID:2726403 | HubMed [PostEtAl89]
  21. White JM, Levi DM, and Aitsebaomo AP. Spatial localization without visual references. Vision Res. 1992 Mar;32(3):513-26. PubMed ID:1604838 | HubMed [WhiteLeviAitsebaomo1992]
All Medline abstracts: PubMed | HubMed