Psychophysics, Estimating Perceptual Scales with Interval Properties - PowerPoint PPT Presentation

Psychophysics, Estimating Perceptual Scales with Interval Properties qu’est-ce que c’est ? Kenneth Knoblauch � & Laurence T. Maloney � Gustav Fechner (1801 - 1887) 1. Inserm, U846 Stem Cell and Brain Research Institute A body of techniques and analytic methods to study the Dept. Integrative Neurosciences relation between physical stimuli and the organism’s Bron, France (classification) behavior to infer internal states of the organism or their organization. 2. Department of Psychology Center for Neural Science New York University New York, NY 10003, USA Classical Psychophysical Paradigm Average ModelFest Data Event Observer Response -0.5 Suprathreshold -1.0 Log Contrast Threshold φ i ∈ { φ 1 , · · · , φ n } -1.5 1.0 R ij ∈ { R 11 , R 12 , . . . , R np } 0.8 ψ j ∈ { ψ 1 , · · · , ψ m } Proportion Correct 0.6 + ǫ -2.0 0.4 ǫ ∼ i.i.d. 0.2 Subthreshold 0.0 0 1 2 3 4 -2.5 � f is a Psychometric Function Pr ( R ij ) = f ( { φ i } ; Ψ ) , 1 2 5 10 20 Spatial Frequency (c/deg) http://vision.arc.nasa.gov/modelfest/