The Role of Retinal versus Perceived Size in the Effects of Pitched Displays on Visually Perceived Eye Level

Perception ◽  
1996 ◽  
Vol 25 (7) ◽  
pp. 853-859 ◽  
Author(s):  
Robert B Post ◽  
Robert B Welch
Keyword(s):  
Retinal Image ◽  
Horizontal Axis ◽  
Retinal Size ◽  
Image Size ◽  
Large Display ◽  
Large Pair ◽  
Small Display ◽  
Optical Pitch

Visually perceived eye level (VPEL) was measured while subjects viewed two vertical lines which were either upright or pitched about the horizontal axis. In separate conditions, the display consisted of a relatively large pair of lines viewed at a distance of 1 m, or a display scaled to one third the dimensions and viewed at a distance of either 1 m or 33.3 cm. The small display viewed at 33.3 cm produced a retinal image the same size as that of the large display at 1 m. Pitch of all three displays top-toward and top-away from the observer caused upward and downward VPEL shifts, respectively. These effects were highly similar for the large display and the small display viewed at 33.3 cm (ie equal retinal size), but were significantly smaller for the small display viewed at 1 m. In a second experiment, perceived size of the three displays was measured and found to be highly accurate. The results of the two experiments indicate that the effect of optical pitch on VPEL depends on the retinal image size of stimuli rather than on perceived size.

Perceived Angular and Linear Size: The Role of Binocular Disparity and Visual Surround

Perception ◽  
1997 ◽  
Vol 26 (1) ◽  
pp. 17-27 ◽  
Author(s):  
Hirohiko Kaneko ◽  
Keiji Uchikawa
Keyword(s):  
Causal Relationship ◽  
Retinal Image ◽  
Binocular Disparity ◽  
Angular Size ◽  
The Other ◽  
Linear Size ◽  
Image Size ◽  
Other Hand

An experiment was conducted to investigate the effects of perspective cue and binocular disparity on perceived angular and linear size. Following the ‘angular’ and ‘linear’ instructions, subjects matched the size of two squares, for which the binocular disparity between the centers of the squares and the configuration of the stimulus surrounding the squares were manipulated. Results showed that angular-size matches depended on the retinal-image size and the binocular disparity, and not on the visual-surround stimulus. Linear-size matches, on the other hand, depended on the visual-surround stimulus as well as on the image size and the binocular disparity. The visual-surround stimulus also affects the perceived depth between the test squares. These findings indicate that perceived angular and linear size depend on different processes that use different cues, and suggest that there is a causal relationship between perceived depth and perceived linear size.

The Role of Familiar Size in the Control of Grasping

2001 ◽  
Vol 13 (1) ◽  
pp. 8-17 ◽  
Author(s):  
J. J. Marotta ◽  
M. A. Goodale
Keyword(s):  
Binocular Vision ◽  
Retinal Image ◽  
Opportunity To Learn ◽  
Image Size ◽  
Familiar Size ◽  
Depth Cue ◽  
On Line ◽  
And Control ◽  
The Relationship

The present study examined whether the learned pictorial depth cue of “familiar size” could be used to plan a reaching and grasping movement in the absence of binocular vision. Sixteen right-handed subjects were presented with two different arrays, under monocular and binocular viewing conditions, in which a range of different “grasp-sized” spheres that were lit from within could be presented in an otherwise darkened environment. In the “familiar-size” presentation array, only one “standard” sized sphere was presented, which gave subjects an opportunity to learn the relationship between the standard sphere's retinal image size and its distance. In the “multiple” spheres presentation array, subjects could not learn such a relationship because on any one trial, one of four different sphere sizes could be present. In a second experiment, the effects of this paradigm on six subjects' perceptual reports of distance were examined by having subjects slide their index fingers apart along a horizontal rod to indicate the estimated distance of the spheres. When familiar size could not be used as a cue to distance, subjects produced more on-line corrections in their reaching and grasping movements to the standard-sized spheres—but only under monocular viewing conditions. It appears that subjects are able to exploit the learned relationship between an object's distance and its projected retinal image size to help program and control reaching and grasping movements when binocular vision is not available. Although the influence of familiar size on subjects' perceptual estimates is less clear, it is clear that subjects' perceptual estimates show poor absolute scaling for distance. This result further supports the notion that under normal viewing conditions the visuomotor system uses binocular information to program and control manual prehension, but is able to use pictorial information when binocular vision is denied.

Do Writing Directions Influence How People Map Space onto Time?

2018 ◽  
Vol 77 (4) ◽  
pp. 173-184
Author(s):  
Wenxing Yang ◽  
Ying Sun
Keyword(s):  
Mental Representations ◽  
Space Time ◽  
Horizontal Axis ◽  
Causal Role ◽  
Writing Systems ◽  
Temporal Cognition ◽  
Japanese Speakers ◽  
Psychological Experiments ◽  
Vertical Up

Abstract. The causal role of a unidirectional orthography in shaping speakers’ mental representations of time seems to be well established by many psychological experiments. However, the question of whether bidirectional writing systems in some languages can also produce such an impact on temporal cognition remains unresolved. To address this issue, the present study focused on Japanese and Taiwanese, both of which have a similar mix of texts written horizontally from left to right (HLR) and vertically from top to bottom (VTB). Two experiments were performed which recruited Japanese and Taiwanese speakers as participants. Experiment 1 used an explicit temporal arrangement design, and Experiment 2 measured implicit space-time associations in participants along the horizontal (left/right) and the vertical (up/down) axis. Converging evidence gathered from the two experiments demonstrate that neither Japanese speakers nor Taiwanese speakers aligned their vertical representations of time with the VTB writing orientation. Along the horizontal axis, only Japanese speakers encoded elapsing time into a left-to-right linear layout, which was commensurate with the HLR writing direction. Therefore, two distinct writing orientations of a language could not bring about two coexisting mental time lines. Possible theoretical implications underlying the findings are discussed.

Visual Acuity Affected by Size Perception Based on Convergence Cue

Perception ◽  
1997 ◽  
Vol 26 (1_suppl) ◽  
pp. 354-354
Author(s):  
H Shinoda ◽  
M Ikeda
Keyword(s):  
Visual Acuity ◽  
Visual System ◽  
Retinal Image ◽  
White Paper ◽  
Retinal Size ◽  
Size Perception ◽  
Convergence Angle ◽  
Threshold Size

Increasing (or decreasing) the convergence angle can shrink (or expand) the perceived size of an object without changing its retinal size (Oyama, 1974 Perception & Psychophysics16 175 – 182). Here we address the question whether such a change in perceived size affects visual acuity. We investigated the effects of perceived size on the legibility of letters, using a telestereoscope consisting of four mirrors to control the observer's convergence angle while keeping the size of the retinal image constant. The targets were photocopies of ordinary Japanese books containing both types of Japanese characters, kana and kanji. The former is a phonetic character and simpler than the latter. Letters were printed in black on white paper. First, we demonstrated that letters do become more legible (illegible) as perceived size expands (shrinks), although their retinal size does not change. Then, we measured the size of the convergence angle at which letters became legible. The ‘threshold’ size of the convergence angle was obtained for several retinal sizes (0.1 to 0.2 deg) of letters, and for kana and kanji, respectively. Four subjects participated in the experiment. The result shows that the threshold convergence angle for legibility decreases as the retinal size of letters decreases, so that the minimum retinal size of legible letters depends linearly on the convergence angle. The results implicate contributions from higher levels of the visual system to the determination of visual acuity.

The role of image size in the recognition of conversational facial expressions

2004 ◽  
Vol 15 (34) ◽  
pp. 305-310 ◽  
Author(s):  
Douglas W. Cunningham ◽  
Manfred Nusseck ◽  
Christian Wallraven ◽  
Heinrich H. Bülthoff
Keyword(s):  
Facial Expressions ◽  
Image Size

Size-Analysis of Retinal Images by Orientation Detectors

1980 ◽  
Vol 51 (3_suppl2) ◽  
pp. 1307-1330
Author(s):  
Willard L. Brigner
Keyword(s):  
Retinal Image ◽  
Size Analysis ◽  
Retinal Images ◽  
Image Size

A model for the determination of retinal-image size is presented. The size-analysis is based upon the range of orientation detectors activated by a stimulus. The model is applied to size aftereffects and is also used to predict changes in perceived size in configurations which may be expected to affect the range of orientation detectors activated. The relevance of the model to illusions of direction and the perceived length of lines forming angles is also discussed.

Decoupling the role of image size and calorie intake on gastric retention of swelling-based gastric retentive formulations: Pre-screening in the dog model

2012 ◽  
Vol 431 (1-2) ◽  
pp. 90-100 ◽  
Author(s):  
Anita K. Lalloo ◽  
Emma L. McConnell ◽  
Lan Jin ◽  
Richard Elkes ◽  
Christian Seiler ◽  
...  
Keyword(s):  
Calorie Intake ◽  
Gastric Retention ◽  
Image Size ◽  
Dog Model

Role of Retinal Image Motion in Evoking the McCollough Effect

1973 ◽  
Vol 245 (147) ◽  
pp. 255-256 ◽  
Author(s):  
DAVID J. PIGGINS ◽  
PETER K. LEPPMANN
Keyword(s):  
Retinal Image ◽  
Mccollough Effect ◽  
Image Motion ◽  
Retinal Image Motion
Sign in / Sign up

Export Citation Format

Share Document