title: Spatial-frequency masking and Birdsall's theorem.
abstract: We measured the masking of a spatial 4-cycle/deg sinusoid in the presence of both random and sinusoidal masks. Subjects used a variety of detection strategies, depending on psychophysical technique and familiarity with the mask. Some strategies produce Weber's-law behavior and appear formally equivalent to identification tasks; we hypothesize that these exemplify the operation of Birdsall's theorem. Other strategies produce power-law behavior and are more like the simpler detection task. Our results suggest that criterion change (commonly uncontrolled in masking studies) can produce an unacceptably large bias in the results.
mesh_terms: D001288:Attention; D002755:Choice Behavior; D005556:Form Perception; D006801:Humans; D009039:Motion Perception; D010364:Pattern Recognition, Visual; D010470:Perceptual Masking; D011601:Psychophysics; D012684:Sensory Thresholds; D012718:Set, Psychology; D013028:Space Perception