| Records |
| Author |
Macuda, T.; Timney, B. |
| Title |
Luminance and chromatic discrimination in the horse (Equus caballus) |
Type |
Journal Article |
Year  |
1999 |
Publication |
Behavioural Processes |
Abbreviated Journal |
Behav. Process. |
| Volume |
44 |
Issue |
3 |
Pages |
301-307 |
| Keywords |
Colour vision; Chromatic discrimination; Luminance discrimination; Horse |
| Abstract |
Equine colour vision was measured under conditions that minimised the possibility of animals using brightness cues to make chromatic discriminations. In a two-stage study, we first obtained luminance discrimination functions for achromatic targets then tested for chromatic discrimination over a range of target luminances. Horses were trained on a two-choice discrimination task. The positive stimulus was varied in luminance and/or colour using neutral density and broad band colour filters. The negative stimulus appeared as a uniform grey. In the brightness discrimination task, the horses performed well at large luminance differences but their percentage of correct responses declined to near chance levels at differences of less than 0.2 log units. In addition, a decrement in performance was noted at luminance differences of less than 0.2 log units for green and yellow chromatic discrimination functions, suggesting that horses cannot easily discriminate yellow and green from grey. However, the chromatic discrimination functions for red and blue showed that animals performed very well across the full range of target luminances. These results suggest that horses are at least dichromats. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Summary Language |
|
Original Title |
|
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
|
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
|
Approved |
no |
| Call Number |
refbase @ user @ |
Serial |
844 |
| Permanent link to this record |
| |
|
| |
| Author |
Smith, S.; Goldman, L. |
| Title |
Color discrimination in horses |
Type |
Journal Article |
| Year |
1999 |
Publication |
Applied Animal Behaviour Science |
Abbreviated Journal |
Appl. Anim. Behav. Sci. |
| Volume |
62 |
Issue |
1 |
Pages |
13-25 |
| Keywords |
Horses; Vision; Color; Discrimination; Behavior |
| Abstract |
Four Arabian horses and one Thoroughbred were presented with a series of two-choice color vs. gray discrimination problems. Testing was done in a stall containing a wall with two translucent panels that were illuminated from behind by light projected through color or gray filters to provide the discriminative stimuli. Horses first learned to push one of the panels in order to receive the food reward behind the positive stimulus in an achromatic light-dark discrimination task, and were then tested on their ability to discriminate between gray and four individual colors: red (617 nm), yellow (581 nm), green (538 nm), and blue (470 nm). The criterion for learning was set at 85% correct responses, and final testing for all color vs. gray discriminations involved grays of varying intensities, making brightness an irrelevant cue. Three subjects were tested with all four colors. Two of those subjects successfully reached the criterion for learning on all four color vs. gray discriminations, while the third reached criterion with red and blue, but performed at chance levels for yellow and green. A fourth horse was only tested with green and yellow, and a fifth only with blue, and both of those horses successfully reached criterion on the discriminations they attempted. With the exception of the one subject's poor performance with yellow and green, there was no significant difference between horses on any of the discrimination tasks, and no significant difference in their performance with different colors. The results suggest that horses have color vision that is at least dichromatic, although partial color-blindness may occur in some individuals. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Summary Language |
|
Original Title |
|
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
|
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
|
Approved |
no |
| Call Number |
refbase @ user @ |
Serial |
850 |
| 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 |
| |
|
| |
| Author |
Lomas, C.A.; Piggins, D.; Phillips, C.J.C. |
| Title |
Visual awareness |
Type |
Journal Article |
| Year |
1998 |
Publication |
Applied Animal Behaviour Science |
Abbreviated Journal |
Appl. Anim. Behav. Sci. |
| Volume |
57 |
Issue |
3-4 |
Pages |
247-257 |
| Keywords |
Visual awareness; Colour vision; Rhythm |
| Abstract |
Awareness varies between different species and humans can never truly appreciate what it is like to be another individual, either of the same species or another. Visual perceptual faculties provide some evidence of the extent to which domesticated animals derive information from objects in their environment, whilst changes in behaviour resulting from different visual stimuli can also provide valuable information on the state of visual awareness. Extensive processing of potentially visual information must occur in all domesticated species, but is much less well understood than purely sensory based information. For example, sensory aspects of colour vision are reasonably well understood, but the role of wavelength variables in an animal's cognition and its colour experience is not clear. Considerable use is made of diurnal changes in photoperiod to synchronise endogenous rhythms to particular times of the day and the year. Variation in light intensity in natural images is also important for social reasons for animals to be able to discriminate between, e.g., different faces, but little is known about intensity preferences or the effects of intensity on behaviour. It appears likely that in many cases visual stimuli represent some of the most important influences on an animal's awareness, either alone or in combination with, e.g., olfactory cues. However, a much greater understanding of their processing is required before we can make useful deductions about visual awareness in domesticated animals. |
| Address |
|
| Corporate Author |
|
Thesis |
|
| Publisher |
|
Place of Publication |
|
Editor |
|
| Language |
|
Summary Language |
|
Original Title |
|
| Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
|
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
|
Approved |
no |
| Call Number |
Equine Behaviour @ team @ |
Serial |
4309 |
| Permanent link to this record |
| |
|
| |
| Author |
Loveland, K.A. |
| Title |
Self-recognition in the bottlenose dolphin: ecological considerations |
Type |
Journal Article |
| Year |
1995 |
Publication |
Consciousness and Cognition |
Abbreviated Journal |
Conscious Cogn |
| Volume |
4 |
Issue |
2 |
Pages |
254-257 |
| Keywords |
Animals; Attention; *Awareness; Body Image; Dolphins/*psychology; Exploratory Behavior; Female; Male; *Self Concept; *Social Environment; Species Specificity; Television; *Visual Perception |
| Abstract |
|
| Address |
Department of Psychiatry and Behavioral Sciences, University of Texas Medical School, Houston 77025, USA |
| 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 |
1053-8100 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
PMID:8521267 |
Approved |
no |
| Call Number |
Equine Behaviour @ team @ |
Serial |
4161 |
| Permanent link to this record |
| |
|
| |
| Author |
Hart, D.; Whitlow, J.W.J. |
| Title |
The experience of self in the bottlenose dolphin |
Type |
Journal Article |
| Year |
1995 |
Publication |
Consciousness and Cognition |
Abbreviated Journal |
Conscious Cogn |
| Volume |
4 |
Issue |
2 |
Pages |
244-247 |
| Keywords |
Animal Communication; Animals; *Awareness; Body Image; Dolphins/*psychology; Female; Humans; Male; *Self Concept; Social Behavior; Species Specificity; *Television; *Visual Perception |
| Abstract |
Marten and Psarakos have presented some evidence which suggests that objective self-awareness and possibly representations of self may characterize the dolphins' experience of self. Their research demonstrates the possibility of similarities in the sense of self between primate species and dolphins, although whether dolphins have subjective self-awareness, personal memories, and theories of self--all important facets of the sense of self in humans--was not examined. Clearly, even this limited evidence was difficult to achieve; the difficulties in adapting methods and coding behavior are quite apparent in their report. Future progress, however, may depend upon clarification of what are the necessary components for a sense of self and an explication of how these might be reflected in dolphin behavior. We are mindful of the authors' point (pp. 219 and 220) that the dolphin lives more in an acoustic than a visual environment. Thus, while tasks relying upon vision may reveal the presence or absence of the sense of self in primates, it might well be the case that in dolphins self-related experiences might be better revealed in auditory tasks. But then, what is the nature of human self-awareness in terms of audition? While both conceptual and methodological hurdles remain, Marten and Psarakos have demonstrated that important questions can be asked about the minds and phenomenal worlds of nonanthropoid species. |
| Address |
Department of Psychology, Rutgers University, Camden, New Jersey 08102, USA |
| 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 |
1053-8100 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
PMID:8521264 |
Approved |
no |
| Call Number |
Equine Behaviour @ team @ |
Serial |
4162 |
| Permanent link to this record |
| |
|
| |
| Author |
Anderson, J.R. |
| Title |
Self-recognition in dolphins: credible cetaceans; compromised criteria, controls, and conclusions |
Type |
Journal Article |
| Year |
1995 |
Publication |
Consciousness and Cognition |
Abbreviated Journal |
Conscious Cogn |
| Volume |
4 |
Issue |
2 |
Pages |
239-243 |
| Keywords |
Animal Communication; Animals; *Awareness; Discrimination Learning; Dolphins/*psychology; Female; Male; Orientation; *Self Concept; Social Behavior; *Television; *Visual Perception |
| Abstract |
|
| Address |
Laboratoire de Psychophysiologie, CNRS URA 1295, Universite Louis Pasteur, Strasbourg, France |
| 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 |
1053-8100 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
PMID:8521263 |
Approved |
no |
| Call Number |
Equine Behaviour @ team @ |
Serial |
4163 |
| Permanent link to this record |
| |
|
| |
| Author |
Marten, K.; Psarakos, S. |
| Title |
Using self-view television to distinguish between self-examination and social behavior in the bottlenose dolphin (Tursiops truncatus) |
Type |
Journal Article |
| Year |
1995 |
Publication |
Consciousness and Cognition |
Abbreviated Journal |
Conscious Cogn |
| Volume |
4 |
Issue |
2 |
Pages |
205-224 |
| Keywords |
Animal Communication; Animals; *Attention; Discrimination Learning; Dolphins/*psychology; Female; Male; *Self Concept; *Social Behavior; *Television; *Visual Perception |
| Abstract |
In mirror mark tests dolphins twist, posture, and engage in open-mouth and head movements, often repetitive. Because postures and an open mouth are also dolphin social behaviors, we used self-view television as a manipulatable mirror to distinguish between self-examination and social behavior. Two dolphins were exposed to alternating real-time self-view (“mirror mode”) and playback of the same to determine if they distinguished between them. The adult male engaged in elaborate open-mouth behaviors in mirror mode, but usually just watched when played back the same material. Mirror mode behavior was also compared to interacting with real dolphins (controls). Mark tests were conducted, as well as switches from front to side self-views to see if the dolphins turned. They presented marked areas to the self-view television and turned. The results suggest self-examination over social behavior. |
| Address |
Earthtrust, Kailua, Hawaii 96734, USA |
| 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 |
1053-8100 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
PMID:8521259 |
Approved |
no |
| Call Number |
Equine Behaviour @ team @ |
Serial |
4164 |
| Permanent link to this record |
| |
|
| |
| Author |
Wolfe, J.M. |
| Title |
Hidden visual processes |
Type |
Journal Article |
| Year |
1983 |
Publication |
Scientific American |
Abbreviated Journal |
Sci Am |
| Volume |
248 |
Issue |
2 |
Pages |
94-103 |
| Keywords |
Color Perception/*physiology; Humans; Motion Perception/physiology; Ocular Physiology; Vision; Visual Perception/*physiology |
| Abstract |
Isoluminant stimulus is an image whose edges are defined only by a change in color, not by change in brightness. The stimulus here is imperfect: the blue parts and the green parts of the image are only as nearly equal in brightness as they can be on the printed page. Moreover, the change in brightness beyond the edge of the page is apparent, and so is the fact that the reader is holding the magazine at reading distance. When such cues are removed under laboratory conditions, subjects faced with an isoluminant stimulus prove unable to bring its edges into focus. This deficiency contributes to making a familiar face hard to recognize. The experiment indicates that the brain process underlying visual accommodation (the focusing of the eyes) cannot “see” color; it is a hidden process distinct from the processes that lead to perception. The image shows Groucho Marx as he appeared in the motion picture Horse Feathers. |
| Address |
|
| 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 |
0036-8733 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
PMID:6836258 |
Approved |
no |
| Call Number |
Equine Behaviour @ team @ |
Serial |
4066 |
| Permanent link to this record |
| |
|
| |
| Author |
van Niekerk, H.P. |
| Title |
Ethological studies within the man-horse relationship |
Type |
Journal Article |
| Year |
1980 |
Publication |
Journal of the South African Veterinary Association |
Abbreviated Journal |
J S Afr Vet Assoc |
| Volume |
51 |
Issue |
4 |
Pages |
237-238 |
| Keywords |
Animals; Behavior, Animal; Hearing; Horses/*physiology; Humans; Smell; Taste; Touch; Vision |
| Abstract |
Certain aspects of ethology and the horse's senses are discussed to bring about a better understanding between man and horse. Furthermore the behaviour of horses with respect to housing, feeding, breeding, veterinary treatment and work are considered. |
| Address |
|
| 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 |
1019-9128 |
ISBN |
|
Medium |
|
| Area |
|
Expedition |
|
Conference |
|
| Notes |
PMID:7241494 |
Approved |
no |
| Call Number |
refbase @ user @ |
Serial |
1960 |
| Permanent link to this record |
