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- All Subjects: Timing
- Creators: Homa, Donald
Description
In baseball, the difference between a win and loss can come down to a single call, such as when an umpire judges force outs at first base by typically comparing competing auditory and visual inputs of the ball-mitt sound and the foot-on-base sight. Yet, because the speed of sound in air only travels about 1100 feet per second, fans observing from several hundred feet away will receive auditory cues that are delayed a significant portion of a second, and thus conceivably could systematically differ in judgments compared to the nearby umpire. The current research examines two questions. 1. How reliably and with what biases do observers judge the order of visual versus auditory events? 2. Do observers making such order judgments from far away systematically compensate for delays due to the slow speed of sound? It is hypothesized that if any temporal bias occurs it is in the direction consistent with observers not accounting for the sound delay, such that increasing viewing distance will increase the bias to assume the sound occurred later. It was found that nearby observers are relatively accurate at judging if a sound occurred before or after a simple visual event (a flash), but exhibit a systematic bias to favor visual stimuli occurring first (by about 30 msec). In contrast, distant observers did not compensate for the delay of the speed of sound such that they systematically favored the visual cue occurring earlier as a function of viewing distance. When observers judged simple visual stimuli in motion relative to the same sound burst, the distance effect occurred as a function of the visual clarity of the ball arriving. In the baseball setting, using a large screen projection of baserunner, a diminished distance effect occurred due to the additional visual cues. In summary, observers generally do not account for the delay of sound due to distance.
ContributorsKrynen, R. Chandler (Author) / McBeath, Michael (Thesis advisor) / Homa, Donald (Committee member) / Gray, Robert (Committee member) / Arizona State University (Publisher)
Created2017
Description
Color perception has been widely studied and well modeled with respect to combining visible electromagnetic frequencies, yet new technology provides the means to better explore and test novel temporal frequency characteristics of color perception. Experiment 1 tests how reliably participants categorize static spectral rainbow colors, which can be a useful tool for efficiently identifying those with functional dichromacy, trichromacy, and tetrachromacy. The findings confirm that all individuals discern the four principal opponent process colors, red, yellow, green, and blue, with normal and potential tetrachromats seeing more distinct colors than color blind individuals. Experiment 2 tests the moving flicker fusion rate of the central electromagnetic frequencies within each color category found in Experiment 1 as a test of the Where system. It then compares this to the maximum temporal processing rate for discriminating direction of hue change with colors displayed serially as a test of the What system. The findings confirm respective processing thresholds of about 20 Hz for Where and 2-7 Hz for What processing systems. Experiment 3 tests conditions that optimize false colors based on the spinning Benham’s Top illusion. Findings indicate the same four principal colors emerge as in Experiment 1, but at low saturation levels for trichromats that diminish further for dichromats. Taken together, the three experiments provide an overview of the common categorical boundaries and temporal processing limits of human color vision.
ContributorsKrynen, Richard Chandler (Author) / Mcbeath, Michael K (Thesis advisor) / Homa, Donald (Committee member) / Newman, Nathan (Committee member) / Stone, Greg (Committee member) / Arizona State University (Publisher)
Created2021