| Second-order optic flow processing. | |
| | |
MedLine Citation:
|
PMID: 17462696 Owner: NLM Status: MEDLINE |
Abstract/OtherAbstract:
|
Optic flow-large-field rotational and radial motion-is processed as efficiently as translational motion for first-order (luminance-defined) stimuli. However, it has been suggested recently that the same pattern does not hold for second-order (e.g. contrast-defined) stimuli. We used random dot kinematogram (RDK) stimuli to determine whether global processing of optic flow is as efficient as processing of global translational motion for both first- and second-order stimuli. For first-order stimuli, we found that coherence thresholds for radial and rotational motion were equivalent to thresholds for translational motion, supporting previous findings. For second-order stimuli we found, firstly, that given sufficient contrast, second-order optic flow can be processed as efficiently as first-order optic flow and, secondly, that rotational and translational second-order motion are processed with equal efficiency. This contradicts the suggestion that there is a loss of efficiency between integration of second-order global motion and second-order optic flow. The third interesting finding was that the processing of radial second-order motion appears to suffer from a deficit that is dependent upon both the contrast and spatial extent of the stimulus. Further experiments discounted the possibility that the observed deficit is caused by a centrifugal or centripetal bias, but demonstrated that a longer temporal integration period for radial second-order motion is responsible for the observed difference. For durations of approximately 850ms, all three types of motion are processed with equal efficiency. |
| | |
Authors:
|
Craig Aaen-Stockdale; Tim Ledgeway; Robert F Hess |
Related Documents
:
|
8351836 - Spatiotemporal properties of motion perception for random-check contrast modulations. 20089816 - Processing of horizontal optic flow in three visual interneurons of the drosophila brain. 2030936 - Perceptual constancy during ocular pursuit: a quantitative estimation procedure. 15521696 - Jitter and size effects on vection are immune to experimental instructions and demands. 16659366 - Control by phytochrome of cytoplasmic and plastid rrna accumulation in cotyledons of mu... 10197756 - The effectiveness of light on the circadian clock is linked to its emotional value. |
Publication Detail:
|
Type: Journal Article Date: 2007-04-25 |
Journal Detail:
|
Title: Vision research Volume: 47 ISSN: 0042-6989 ISO Abbreviation: Vision Res. Publication Date: 2007 Jun |
Date Detail:
|
Created Date: 2007-05-22 Completed Date: 2007-08-10 Revised Date: - |
Medline Journal Info:
|
Nlm Unique ID: 0417402 Medline TA: Vision Res Country: England |
Other Details:
|
Languages: eng Pagination: 1798-808 Citation Subset: IM |
Affiliation:
|
Department of Ophthalmology, McGill Vision Research, McGill University, Royal Victoria Hospital, 687 Pine Ave West, Rm H4-14, Montreal, Que., Canada H3A 1A1. |
Export Citation:
|
APA/MLA Format Download EndNote Download BibTex |
| MeSH Terms | |
Descriptor/Qualifier:
|
Adult Contrast Sensitivity Depth Perception Humans Motion Perception* Photic Stimulation / methods Psychophysics Rotation Sensory Thresholds Space Perception Time Factors |
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine
Previous Document: Abutilon mosaic virus DNA B component supports mechanical virus transmission, but does not counterac...
Next Document: Intrinsic growth rate: a new approach to evaluate the effects of temperature, photoperiod and phosph...