title: Spatial frequency discrimination: visual long-term memory or criterion setting?
abstract: A long-term sensory memory is believed to account for spatial frequency discrimination when reference and test stimuli are separated by long intervals. We test an alternative proposal: that discrimination is determined by the range of test stimuli, through their entrainment of criterion-setting processes. Experiments 1 and 2 show that the 50% point of the psychometric function is largely determined by the midpoint of the stimulus range, not by the reference stimulus. Experiment 3 shows that discrimination of spatial frequencies is similarly affected by orthogonal contextual stimuli and parallel contextual stimuli and that these effects can be explained by criterion-setting processes. These findings support the hypothesis that discrimination over long intervals is explained by the operation of criterion-setting processes rather than by long-term sensory retention of a neural representation of the stimulus.
authors.affiliation: Department of Experimental Psychology, Oxford University, U.K.
authors.forename: M
authors.initials: M
authors.lastname: Lages
authors.forename: M
authors.initials: M
authors.lastname: Treisman
mesh_terms: D000328:Adult; D004192:Discrimination, Psychological / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D008568:Memory / Q000502:physiology*; D010364:Pattern Recognition, Visual / Q000502:physiology*; D011594:Psychometrics; D013997:Time Factors