scholarly journals The extra-retinal motion aftereffect

2003 ◽  
Vol 3 (11) ◽  
pp. 11 ◽  
Author(s):  
Tom C. A. Freeman ◽  
Jane H. Sumnall ◽  
Robert J. Snowden
Keyword(s):  
Motion Aftereffect ◽  
Retinal Motion

On Interocular Transfer of Motion Aftereffects

Perception ◽  
1993 ◽  
Vol 22 (11) ◽  
pp. 1365-1380 ◽  
Author(s):  
Nicholas J Wade ◽  
Michael T Swanston ◽  
Charles M M de Weert
Keyword(s):  
Interocular Transfer ◽  
Motion Aftereffect ◽  
Dark Field ◽  
The Other ◽  
Retinal Motion ◽  
Black Field ◽  
History Of ◽  
Contralateral Eye ◽  
Motion Aftereffects ◽  
Motion Detectors

A brief history of quantitative assessments of interocular transfer (IOT) of the motion aftereffect (MAE) is presented. Recent research indicates that the MAE occurs as a consequence of adapting detectors for relative rather than retinal motion. When gratings above and below a stationary, fixated grating are moved in an otherwise dark field the central, retinally stationary grating appears to move in the opposite direction; when tested with stationary gratings an MAE is almost entirely confined to the central grating. The IOT of such an MAE was measured in experiment 1: the display was presented to one eye with a black field in the other. The IOT was about 30% of the monocular MAE. Similar values were found in experiment 2, in which the contralateral eye received an equivalent central stationary grating during adaptation and test. The dichoptic interaction of the processes involved in the MAE was examined by presenting the central gratings to both eyes and a single flanking grating above in one eye and below in the other (experiment 3). The MAE was tested with either the same or the contralateral pairing. Oppositely directed MAEs were found for the central and flanking gratings, but they were confined mainly to the conditions in which the configurations presented during adaptation were present in the same eyes during test. In experiment 4, the surround MAEs were compared after adaptation with two moving gratings in one eye or with a similar dichoptic configuration, and they were of similar duration. In a final experiment the MAE was tested either monocularly or binocularly after alternating adaptation of the left and right eyes and was found to be of the same duration. It is concluded that the MAE is a consequence of adapting relational-motion detectors, which are either monocular or of the binocular OR class.

scholarly journals The perceptual and cortical consequences of adaptation to smooth pursuit: An MEG study of the extra-retinal motion aftereffect

2011 ◽  
Vol 11 (11) ◽  
pp. 531-531
Author(s):  
B. Dunkley ◽  
T. Freeman ◽  
S. Muthukumaraswamy ◽  
K. Singh
Keyword(s):  
Smooth Pursuit ◽  
Motion Aftereffect ◽  
Retinal Motion

scholarly journals Motion versus Position in the Perception of Head-Centred Movement

Perception ◽  
10.1068/p3256 ◽  
2002 ◽  
Vol 31 (5) ◽  
pp. 603-615 ◽  
Author(s):  
Tom C A Freeman ◽  
Jane H Sumnall
Keyword(s):  
Eye Movement ◽  
Linear Trend ◽  
Motion Aftereffect ◽  
Phenomenal Experience ◽  
Global Motion ◽  
Stationary Object ◽  
Retinal Motion ◽  
Random Dot Patterns ◽  
Perceived Motion ◽  
Motion Versus

Observers can recover motion with respect to the head during an eye movement by comparing signals encoding retinal motion and the velocity of pursuit. Evidently there is a mismatch between these signals because perceived head-centred motion is not always veridical. One example is the Filehne illusion, in which a stationary object appears to move in the opposite direction to pursuit. Like the motion aftereffect, the phenomenal experience of the Filehne illusion is one in which the stimulus moves but does not seem to go anywhere. This raises problems when measuring the illusion by motion nulling because the more traditional technique confounds perceived motion with changes in perceived position. We devised a new nulling technique using global-motion stimuli that degraded familiar position cues but preserved cues to motion. Stimuli consisted of random-dot patterns comprising signal and noise dots that moved at the same retinal ‘base’ speed. Noise moved in random directions. In an eye-stationary speed-matching experiment we found noise slowed perceived retinal speed as ‘coherence strength’ (ie percentage of signal) was reduced. The effect occurred over the two-octave range of base speeds studied and well above direction threshold. When the same stimuli were combined with pursuit, observers were able to null the Filehne illusion by adjusting coherence. A power law relating coherence to retinal base speed fit the data well with a negative exponent. Eye-movement recordings showed that pursuit was quite accurate. We then tested the hypothesis that the stimuli found at the null-points appeared to move at the same retinal speed. Two observers supported the hypothesis, a third partially, and a fourth showed a small linear trend. In addition, the retinal speed found by the traditional Filehne technique was similar to the matches obtained with the global-motion stimuli. The results provide support for the idea that speed is the critical cue in head-centred motion perception.

PATHS OF SEEN MOTION AND MOTION AFTEREFFECT

1966 ◽  
Vol 23 (3) ◽  
pp. 1003-1008 ◽  
Author(s):  
SHIGEMASA SUMI
Keyword(s):  
Motion Aftereffect

scholarly journals Through the Neural Magnifying Glass: Visual Acuity and Motion-Aftereffect

i-Perception ◽  
10.1068/ii48 ◽  
2014 ◽  
Vol 5 (5) ◽  
pp. 479-479
Author(s):  
S.C Boyle ◽  
R Jenkins ◽  
M Lages
Keyword(s):  
Visual Acuity ◽  
Motion Aftereffect

Apparent Velocity of Motion Aftereffects in Central and Peripheral Vision

Perception ◽  
1986 ◽  
Vol 15 (5) ◽  
pp. 603-612 ◽  
Author(s):  
Michael J Wright
Keyword(s):  
Visual Field ◽  
Time Course ◽  
Peripheral Vision ◽  
Temporal Frequency ◽  
Motion Aftereffect ◽  
Apparent Velocity ◽  
Real Motion ◽  
Temporal Decay ◽  
Spatial Grain ◽  
Motion Aftereffects

Adapting to a drifting grating (temporal frequency 4 Hz, contrast 0.4) in the periphery gave rise to a motion aftereffect (MAE) when the grating was stopped. A standard unadapted foveal grating was matched to the apparent velocity of the MAE, and the matching velocity was approximately constant regardless of the visual field position and spatial frequency of the adapting grating. On the other hand, when the MAE was measured by nulling with real motion of the test grating, nulling velocity was found to increase with eccentricity. The nulling velocity was constant when scaled to compensate for changes in the spatial ‘grain’ of the visual field. Thus apparent velocity of MAE is constant across the visual field, but requires a greater velocity of real motion to cancel it in the periphery. This confirms that the mechanism underlying MAE is spatially-scaled with eccentricity, but temporally homogeneous. A further indication of temporal homogeneity is that when MAE is tracked, by matching or by nulling, the time course of temporal decay of the aftereffect is similar for central and for peripheral stimuli.

scholarly journals Mental Rotation Meets the Motion Aftereffect: The Role of hV5/MT+ in Visual Mental Imagery

2011 ◽  
Vol 23 (6) ◽  
pp. 1395-1404 ◽  
Author(s):  
Ruth Seurinck ◽  
Floris P. de Lange ◽  
Erik Achten ◽  
Guy Vingerhoets
Keyword(s):  
Mental Rotation ◽  
Mental Imagery ◽  
Parietal Cortex ◽  
Neural Activity ◽  
Posterior Parietal Cortex ◽  
Visual Motion ◽  
Motion Aftereffect ◽  
Mental Rotation Task ◽  
Behavioral Performance ◽  
Visual Mental Imagery

A growing number of studies show that visual mental imagery recruits the same brain areas as visual perception. Although the necessity of hV5/MT+ for motion perception has been revealed by means of TMS, its relevance for motion imagery remains unclear. We induced a direction-selective adaptation in hV5/MT+ by means of an MAE while subjects performed a mental rotation task that elicits imagined motion. We concurrently measured behavioral performance and neural activity with fMRI, enabling us to directly assess the effect of a perturbation of hV5/MT+ on other cortical areas involved in the mental rotation task. The activity in hV5/MT+ increased as more mental rotation was required, and the perturbation of hV5/MT+ affected behavioral performance as well as the neural activity in this area. Moreover, several regions in the posterior parietal cortex were also affected by this perturbation. Our results show that hV5/MT+ is required for imagined visual motion and engages in an interaction with parietal cortex during this cognitive process.

Recovery from Adaptation to Moving Gratings

Perception ◽  
1977 ◽  
Vol 6 (6) ◽  
pp. 719-725 ◽  
Author(s):  
Max J Keck ◽  
Benjamin Pentz
Keyword(s):  
Time Course ◽  
Spontaneous Recovery ◽  
Motion Aftereffect ◽  
Time Decay ◽  
Short Term ◽  
Test Grating ◽  
Test Conditions ◽  
Sinusoidal Gratings ◽  
Short Term Adaptation

Short-term adaptation to moving sinusoidal gratings results in a motion aftereffect which decays in time. The time decay of the motion aftereffect has been measured psychophysically, and it is found to depend on (i) the spontaneous recovery from the adapted state, and (ii) the contrast of the test grating. We have measured the decays for various test conditions. An extrapolation of the measurements allows us to obtain a decay which represents the time course of the spontaneous recovery of the direction-sensitive mechanisms.

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