| Records |
| Author |
Imura, T.; Tomonaga, M. |
| Title |
Perception of depth from shading in infant chimpanzees ( Pan troglodytes) |
Type |
Journal Article |
| Year |
2003 |
Publication |
Animal Cognition |
Abbreviated Journal |
Anim. Cogn. |
| Volume |
6 |
Issue |
4 |
Pages |
253-258 |
| Keywords |
Age Factors; Animals; Contrast Sensitivity/*physiology; Depth Perception/*physiology; Discrimination Learning/*physiology; Female; Male; Pan troglodytes/growth & development/*physiology/*psychology; Pattern Recognition, Visual/physiology |
| Abstract |
We investigated the ability to perceive depth from shading, one of the pictorial depth cues, in three chimpanzee infants aged 4-10 months old, using a preferential reaching task commonly used to study pictorial depth perception in human infants. The chimpanzee infants reached significantly more to three-dimensional toys than to pictures thereof and more to the three-dimensional convex than to the concave. Furthermore, two of the three infants reached significantly more to the photographic convex than to the photographic concave. These infants also looked longer at the photographic convex than the concave. Our results suggest that chimpanzees perceive, at least as early as the latter half of the first year of life, pictorial depth defined by shading information. Photographic convexes contain richer information about pictorial depth (e.g., attached shadow, cast shadow, highlighted area, and global difference in brightness) than simple computer-graphic graded patterns. These cues together might facilitate the infants' perception of depth from shading. |
| Address |
Graduate School of Humanities, Kwansei Gakuin University, Uegahara, Nishinomiya, Hyogo 662-8501, Japan |
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
English |
Summary Language |
|
Original Title |
|
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1435-9448 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
PMID:14610661 |
Approved |
no |
| Call Number |
Equine Behaviour @ team @ |
Serial |
2550 |
| Permanent link to this record |
| |
|
| |
| Author |
Timney, B.; Keil, K. |
| Title |
Local and global stereopsis in the horse |
Type |
Journal Article |
| Year |
1999 |
Publication |
Vision Research |
Abbreviated Journal |
Vision Res |
| Volume |
39 |
Issue |
10 |
Pages |
1861-1867 |
| Keywords |
Animals; Depth Perception/*physiology; Female; Horses/*physiology; Pattern Recognition, Visual/physiology; Psychophysics; Sensory Thresholds/physiology; Vision, Binocular/physiology; Vision, Monocular/physiology |
| Abstract |
Although horses have laterally-placed eyes, there is substantial binocular overlap, allowing for the possibility that these animals have stereopsis. In the first experiment of the present study we measured local stereopsis by obtaining monocular and binocular depth thresholds for renal depth stimuli. On all measures, the horses' binocular performance was superior to their monocular. When depth thresholds were obtained, binocular thresholds were several times superior to those obtained monocularly, suggesting that the animals could use stereoscopic information when it was available. The binocular thresholds averaged about 15 min arc. In the second experiment we obtained evidence for the presence of global stereopsis by testing the animals' ability to discriminate between random-dot stereograms with and without consistent disparity information. When presented with such stimuli they showed a strong preference for the cyclopean equivalent of the positive stimulus with the real depth. These results provide the first behavioral demonstration of a full range of stereoscopic skills in a lateral-eyed mammal. |
| Address |
Department of Psychology, Faculty of Social Science, University of Western Ontario, London, Canada. timney@julian.uwo.ca |
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
English |
Summary Language |
|
Original Title |
|
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
0042-6989 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
PMID:10343877 |
Approved |
yes |
| Call Number |
Equine Behaviour @ team @ |
Serial |
3580 |
| Permanent link to this record |
