Social and Behavioral Sciences Commons^™

Why Use Noise?, Denis G. Pelli, Bart Farell

Biomedical and Chemical Engineering - All Scholarship

Measuring the dependence of visual sensitivity on parameters of the visual stimulus is a mainstay of vision science. However, it is not widely appreciated that visual sensitivity is a product of two factors that are each invariant with respect to many properties of the stimulus and task. By estimating these two factors, one can isolate visual processes more easily than by using sensitivity measures alone. The underlying idea is that noise limits all forms of communication, including vision. As an empirical matter, it is often useful to measure the human observer’s threshold with and without a noise background added to …