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Abstract
The ability to perceive motion is an integral part of visual perception. An individual’s ability to discriminate motion has a marked influence on their survival and capacity to engage with the environment. Past studies on motion perception have been conducted primarily in a laboratory setting, however, limiting their ecological validity. Those that have not were limited in their control of the stimulus and psychophysical methods typically available within a laboratory. The present study implemented a novel, ecologically valid methodology of assessing motion perception performance under the following conditions: no veiling light, white (emulated daylight), and filtered (short-wave, medium-wave, long-wave veils). A xenon bulb was used as the light source, emulating the spectral characteristics of natural daylight; each of the 3 filtered conditions were chosen to isolate a band of the xenon light: short-wave (400nm-500nm), medium-wave (500nm-600nm) and long-wave (600nm-700nm). Motion perception thresholds were measured while these wavebands were interposed as a homogenous veil between the motion stimulus and the eye of the subject. In general, we found that varying spectral content did not change the motion thresholds for the subjects. Macular and iridial pigmentation were not covariates. These results suggest that motion perception is strongly resistant to degradation when tested using a variety of simulated ecological conditions.