Prediction of thresholds and latency on the basis of experimentally determined impulse responses.

As was shown before (Roufs and Blommaert 1981), temporal impulse responses and step responses can be obtained psychophysically using a drift-correcting perturbation technique. In this paper, experimentally determined impulse responses are given for eight subjects using different experimental conditions, i.e. a 1 deg stimulus field at background luminances of 1200 Td and 100 Td, and a point source superimposed on an extended background of the same luminances, which is a possibility to separate transient and sustained processing. For a large class of stimuli, predictions of threshold curves and latency of different time functions are calculated on the basis of these measured impulse responses. Predictions are tested against experimental data. It will be shown that a simple model, only consisting of a linear filter followed by a noisy peak detector, suffices for a fair quantitative description of the available data.