Response Latencies in the YES-NO Signal Detection Situation

Abstract

Response latencies were recorded from observers given the task of detecting sinusoidal signals presented in a white noise background. On each trial, the probability that a signal would be presented was 0.5. The observers indicated their decisions as to whether or not a signal had been presented by pressing buttons. They were instructed to adopt different decision criteria (strict, medium, or lax) for making a YES response during different sessions of the experiment. For most criteria adopted, the mean latency of YES responses was less than the mean latency of NO responses. In addition, the mean latency of YES responses made after a signal had been presented was less than the mean latency of YES responses made after noise alone had been presented. Similarly, the mean latency of NO responses to noise alone was less than the mean latency of NO responses to signals. Latencies varied widely as a function of the criterion adopted. Receiver operating characteristics were constructed from the latency distributions, as well as from the YES and NO responses ignoring latency.