Apparent Motion of a Wallpaper Illusion with Lateral Head Movement

Perception ◽  
1997 ◽  
Vol 26 (1_suppl) ◽  
pp. 281-281
Author(s):  
S Nakamizo ◽  
M Kondo
Keyword(s):  
Apparent Motion ◽  
Head Movement ◽  
Egocentric Distance ◽  
Independent Variable ◽  
Lateral Head

We measured the magnitude and direction of apparent motion of the wallpaper illusion produced by a lateral head movement. The wallpaper illusion was produced by converging on a grating stimulus located between a far and a near grating stimuli placed, respectively, higher and lower than the fixated middle stimulus. The proximal size of the stimuli was held constant. Observers were asked to move their head laterally on a sliding chinrest and to report the magnitude and direction of the apparent motion of each stimulus. The independent variable was the extent (2.5, 5.0, and 7.5 cm) of the head movement. The results for five observers showed that: (a) the larger mean magnitude of apparent motion was associated with larger extent of head movement, and (b) the direction of apparent motion for the far stimulus was the same as that of the head movement, and that for the near stimulus was opposite to that of the head movement. These results are consistent with Gogel's hypothesis of an apparent concomitant motion of the object with head movement when the egocentric distance of the object is misperceived.

Monocular Egocentric Distance Information Generated by Head Movement

1994 ◽  
Vol 6 (3) ◽  
pp. 219-238 ◽  
Author(s):  
Geoffrey P. Bingham ◽  
Michael G. Stassen
Keyword(s):  
Head Movement ◽  
Egocentric Distance ◽  
Distance Information

scholarly journals Comparison between Lateral Head Movement and To-and-Fro Head Movement on Depth Perception from Motion Parallax

i-Perception ◽  
10.1068/ic393 ◽  
2011 ◽  
Vol 2 (4) ◽  
pp. 393-393
Author(s):  
Masahiro Ishii ◽  
Masashi Fujita ◽  
Masayuki Sato
Keyword(s):  
Depth Perception ◽  
Head Movement ◽  
Motion Parallax ◽  
Lateral Head

Two Stages for Depth Integration of Motion Parallax

Perception ◽  
1996 ◽  
Vol 25 (1_suppl) ◽  
pp. 163-163
Author(s):  
H Ujike ◽  
S Saida
Keyword(s):  
Apparent Motion ◽  
Depth Perception ◽  
Head Movement ◽  
Motion Parallax ◽  
Head Movements ◽  
Integration Time ◽  
Motion Signal ◽  
Motion Threshold ◽  
Sinusoidal Gratings ◽  
Two Stages

Motion parallax has been shown to be a principal cue for depth perception under monocular viewing. The simulated depth of stimuli in previous studies has been constant in both magnitude and direction. In the present study we addressed the question how the visual system detects parallactic depth change. To answer this we investigated the temporal characteristics of parallactic depth change and the effect of a motion signal on them. The stimulus consisted of four bands of 15-cycle sinusoidal gratings and parallactic depth was simulated between each band. In experiment 1, we measured the amount of perceived depth change with different frequencies (0.125 to 10 Hz) of simulated depth change and with different velocities (2.5 to 40 cm s−1) of head movements. The result showed the perceived depth change decreased with frequency of depth change, and it increased with head velocity when the frequency was constant. In experiment 2, we measured the motion threshold with different velocities of head movement. The result showed the threshold was constant across different head velocities. In experiment 3, we measured the amount of perceived depth using apparent motion stimuli with the head moving. The result showed depth decreased with SOA of apparent motion stimuli, but there was no effect of different head velocities. The results of these three experiments indicate that parallactic depth change is determined by the duration of simulated depth, which corresponds to the integration time of motion, as well as by the extent of head movement. We conclude that parallactic depth is integrated in two stages: first, integration of motion and, second, integration of motion parallax.

Depth and Motion in Historical Descriptions of Motion Parallax

Perception ◽  
10.1068/p5232 ◽  
2005 ◽  
Vol 34 (10) ◽  
pp. 1263-1273 ◽  
Author(s):  
Hiroshi Ono ◽  
Nicholas J Wade
Keyword(s):  
Motion Perception ◽  
Apparent Motion ◽  
Head Movement ◽  
Motion Parallax ◽  
Stimulus Motion ◽  
Contemporary Research

Motion parallax was described as a cue to depth over 300 years ago and as producing apparent motion over 150 years ago. In recent years, experimental interest in motion parallax has increased, following the rediscovery of the idea that stimulus motion can be yoked to head movement. We compare the historical descriptions with some contemporary research, which indicates how depth and motion perception are dependent on the conditions of stimulation.

scholarly journals Apparent motion of monocular stimuli in different depth planes with lateral head movements

2007 ◽  
Vol 47 (8) ◽  
pp. 1027-1035 ◽  
Author(s):  
K. Shimono ◽  
W.J. Tam ◽  
H. Ono
Keyword(s):  
Apparent Motion ◽  
Head Movements ◽  
Lateral Head

Head Movement Changes Apparent Depth Order in a Motion-Parallax Display

Perception ◽  
1993 ◽  
Vol 22 (6) ◽  
pp. 643-652 ◽  
Author(s):  
Keikichi Hayashibe
Keyword(s):  
Head Movement ◽  
Horizontal Plane ◽  
Motion Parallax ◽  
Apparent Depth ◽  
Visual Depth ◽  
Depth Order ◽  
Direction Of Movement ◽  
Random Dot Pattern ◽  
Lateral Head

The hypothesis that the apparent visual depth is determined by the proximal velocity relative to the position of the head was examined in three experiments. Apparent protrusion/recession changed when subjects observed a moving random-dot pattern with their heads tilted sideways or rotated in the horizontal plane. This is ascribed to lateral head movement, which increases the proximal velocity when the dots and the subjects' heads are moving in opposite directions, and decreases the proximal velocity when both are moving in the same direction. Changes in the direction of movement of the stimulus caused a reversal of the apparent protrusion/recession. The resultant proximal velocity of the stimulus determined the order of depth of surfaces when the movement of the stimulus was linked to the subject's head movement.

Apparent Depth with Motion Aftereffect and Head Movement

Perception ◽  
1994 ◽  
Vol 23 (10) ◽  
pp. 1241-1248 ◽  
Author(s):  
Hiroshi Ono ◽  
Hiroyasu Ujike
Keyword(s):  
Decay Time ◽  
Head Movement ◽  
Motion Aftereffect ◽  
Apparent Depth ◽  
Shearing Motion ◽  
Lateral Head ◽  
Do So

Coupling a motion aftereffect (MAE) produced by horizontal shearing motion with a lateral head movement yields apparent depth. In experiments 1 and 2, respectively, the magnitude and the decay time of this apparent depth were measured. In experiment 3, it was found that the stimulus that produced an MAE in experiments 1 and 2 failed to do so when it was viewed while the head moved leftward and rightward and depth was seen.

scholarly journals Effects of damping head movement and facial expression in dyadic conversation using real–time facial expression tracking and synthesized avatars

2009 ◽  
Vol 364 (1535) ◽  
pp. 3485-3495 ◽  
Author(s):  
Steven M. Boker ◽  
Jeffrey F. Cohn ◽  
Barry-John Theobald ◽  
Iain Matthews ◽  
Timothy R. Brick ◽  
...  
Keyword(s):  
Experimental Design ◽  
Facial Expression ◽  
Real Time ◽  
Facial Expressions ◽  
Head Movement ◽  
Head Movements ◽  
Head Nodding ◽  
Lateral Head

When people speak with one another, they tend to adapt their head movements and facial expressions in response to each others' head movements and facial expressions. We present an experiment in which confederates' head movements and facial expressions were motion tracked during videoconference conversations, an avatar face was reconstructed in real time, and naive participants spoke with the avatar face. No naive participant guessed that the computer generated face was not video. Confederates' facial expressions, vocal inflections and head movements were attenuated at 1 min intervals in a fully crossed experimental design. Attenuated head movements led to increased head nods and lateral head turns, and attenuated facial expressions led to increased head nodding in both naive participants and confederates. Together, these results are consistent with a hypothesis that the dynamics of head movements in dyadicconversation include a shared equilibrium. Although both conversational partners were blind to the manipulation, when apparent head movement of one conversant was attenuated, both partners responded by increasing the velocity of their head movements.

174: Heat as an Independent Variable in the Development of Rat Testicles During Different Stages of Life

2004 ◽  
Vol 171 (4S) ◽  
pp. 46-46
Author(s):  
Andy Yu-How Chang ◽  
Andrew Hwang ◽  
Hei Wen Xie ◽  
Jie Cai ◽  
Susan Groshen ◽  
...  
Keyword(s):  
Independent Variable
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