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1 June 1992 Effect of spatial frequency content of the background on visual detection of a known target
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It is known that the human visual system has varying sensitivity to different spatial frequencies. We are attempting to develop a better understanding of the interaction between the target and surround in a visual detection task, by changing the properties of the surround in frequency space. In our experiments, a known target is superimposed on a bandwidth- limited Gaussian noise background. The size, brightness, and position of the target are kept constant. The experimental design is a `Signal Known Exactly' ROC experiment. For each background the observer knows that there is a 50% probability that the target is present. The observer is asked to state a confidence level from 1 to 5 that a target is present in a given background. Detection performance for backgrounds with different frequency content is compared using the area under the ROC curve. The results of these experiments indicate that performance varies markedly as the frequency content of the background is changed. Observer performance dropped to a minimum when the background frequency was close to the frequency of maximum contrast sensitivity of the human visual system.
© (1992) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
William M. Gentles, Thanh Nguyen, William K.B. Ho, Curtis B. Caldwell, Lisa E. Ehrlich, Charlene Leonhardt, and Rick Reed "Effect of spatial frequency content of the background on visual detection of a known target", Proc. SPIE 1652, Medical Imaging VI: Image Processing, (1 June 1992);


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