Characterizing the spatial-frequency sensitivity of perceptual templates.
Filtered external noise has been an important tool in characterizing the spatial-frequency sensitivity of perceptual templates. Typically, low-pass- and/or high-pass-filtered external noise is added to the signal stimulus. Thresholds, the signal energy necessary to maintain given criterion performance levels, are measured as functions of the spatial-frequency passband of the external noise. An observer model is postulated to segregate the impact of the external noise and the internal noise. The spatial-frequency sensitivity of the perceptual template is determined by the relative impact exerted by external noise in each frequency band. The perceptual template model (PTM) is a general observer model that provides an excellent account of human performance in white external noise [Vision Res. 38, 1183 (1998); J. Opt. Soc. Am. A 16, 764 (1999)]. We further develop the PTM for filtered external noise and apply it to derive the spatial-frequency sensitivity of perceptual templates.
Lu
Z L
ZL
Department of Psychology, University of Southern California, Los Angeles 90089-1061, USA. zhonglin@rcf.usc.edu
Dosher
B A
BA
D006801:Humans; D008959:Models, Neurological; D009622:Noise; D010470:Perceptual Masking; D011594:Psychometrics / Q000379:methods; D012680:Sensitivity and Specificity; D012684:Sensory Thresholds; D014796:Visual Perception / Q000502:physiology*