scholarly journals The stroboscopic Pulfrich effect is not evidence for the joint encoding of motion and depth

10.1167/5.5.3 ◽  
2005 ◽  
Vol 5 (5) ◽  
pp. 3 ◽  
Author(s):  
Jenny C. A. Read ◽  
Bruce G. Cumming
Keyword(s):  
Pulfrich Effect ◽  
Joint Encoding

Joint-encoding of motion and depth by visual cortical neurons: neural basis of the Pulfrich effect

10.1038/87462 ◽  
2001 ◽  
Vol 4 (5) ◽  
pp. 513-518 ◽  
Author(s):  
Akiyuki Anzai ◽  
Izumi Ohzawa ◽  
Ralph D. Freeman
Keyword(s):  
Cortical Neurons ◽  
Neural Basis ◽  
Pulfrich Effect ◽  
Visual Cortical ◽  
Joint Encoding

Pulfrich Effect for Vision Therapy

2017 ◽  
Vol 1 (1) ◽  
Author(s):  
Pellumb  Kllogjeri
Keyword(s):  
Pulfrich Effect ◽  
Vision Therapy

scholarly journals Effect of Interocular Delay on Disparity-Selective V1 Neurons: Relationship to Stereoacuity and the Pulfrich Effect

2005 ◽  
Vol 94 (2) ◽  
pp. 1541-1553 ◽  
Author(s):  
Jenny C. A. Read ◽  
Bruce G. Cumming
Keyword(s):  
Stereo Matching ◽  
Striate Cortex ◽  
Temporal Integration ◽  
Gaussian Function ◽  
Great Majority ◽  
Integration Time ◽  
V1 Neurons ◽  
Temporal Properties ◽  
Pulfrich Effect ◽  
Behaving Monkeys

The temporal properties of disparity-sensitive neurons place important temporal constraints on stereo matching. We examined these constraints by measuring the responses of disparity-selective neurons in striate cortex of awake behaving monkeys to random-dot stereograms that contained interocular delays. Disparity selectivity was gradually abolished by increasing interocular delay (when the delay exceeds the integration time, the inputs from the 2 eyes become uncorrelated). The amplitude of the disparity-selective response was a Gaussian function of interocular delay, with a mean of 16 ms (±5 ms, SD). Psychophysical measures of stereoacuity, in both monkey and human observers, showed a closely similar dependency on time, suggesting that temporal integration in V1 neurons is what determines psychophysical matching constraints over time. There was a slight but consistent asymmetry in the neuronal responses, as if the optimum stimulus is one in which the right stimulus leads by about 4 ms. Because all recordings were made in the left hemisphere, this probably reflects nasotemporal differences in conduction times; psychophysical data are compatible with this interpretation. In only a few neurons (5/72), interocular delay caused a change in the preferred disparity. Such tilted disparity/delay profiles have been invoked previously to explain depth perception in the stroboscopic version of the Pulfrich effect (and other variants). However, the great majority of the neurons did not show tilted disparity/delay profiles. This suggests that either the activity of these neurons is ignored when viewing Pulfrich stimuli, or that current theories relating neuronal properties to perception in the Pulfrich effect need to be reevaluated.

scholarly journals Contact lenses, the reverse Pulfrich effect, and anti-Pulfrich monovision corrections

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Victor Rodriguez-Lopez ◽  
Carlos Dorronsoro ◽  
Johannes Burge
Keyword(s):  
Processing Speed ◽  
Moving Objects ◽  
Contact Lenses ◽  
Three Dimensional ◽  
Effect Sizes ◽  
Reported Effect ◽  
Pulfrich Effect ◽  
Image Blur ◽  
Optical Blur ◽  
Large Magnification

Abstract Interocular differences in image blur can cause processing speed differences that lead to dramatic misperceptions of the distance and three-dimensional direction of moving objects. This recently discovered illusion—the reverse Pulfrich effect—is caused by optical conditions induced by monovision, a common correction for presbyopia. Fortunately, anti-Pulfrich monovision corrections, which darken the blurring lens, can eliminate the illusion for many viewing conditions. However, the reverse Pulfrich effect and the efficacy of anti-Pulfrich corrections have been demonstrated only with trial lenses. This situation should be addressed, for clinical and scientific reasons. First, it is important to replicate these effects with contact lenses, the most common method for delivering monovision. Second, trial lenses of different powers, unlike contacts, can cause large magnification differences between the eyes. To confidently attribute the reverse Pulfrich effect to interocular optical blur differences, and to ensure that previously reported effect sizes are reliable, one must control for magnification. Here, in a within-observer study with five separate experiments, we demonstrate that (1) contact lenses and trial lenses induce indistinguishable reverse Pulfrich effects, (2) anti-Pulfrich corrections are equally effective when induced by contact and trial lenses, and (3) magnification differences do not cause or impact the Pulfrich effect.

scholarly journals All Pulfrich-like illusions can be explained without joint encoding of motion and disparity

2005 ◽  
Vol 5 (11) ◽  
pp. 1 ◽  
Author(s):  
Jenny C. A. Read ◽  
Bruce G. Cumming
Keyword(s):  
Joint Encoding

scholarly journals A 7 bit 1 GS/s pipelined folding and interpolating ADC with coarse-stage-free joint encoding

2014 ◽  
Vol 11 (12) ◽  
pp. 20140371-20140371 ◽  
Author(s):  
Mingshuo Wang ◽  
Li Lin ◽  
Fan Ye ◽  
Junyan Ren
Keyword(s):  
Joint Encoding
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