The effect of ‘ unwanted’ signals on performance in a vigilance task: a reply to Jerison

Abstract

Jerison's remarks (Ergonomics, 1966, 9, 413) are discussed in relation to the results of a further experiment on ' unwanted ' signals in which (a) the original interaction between the effects of signal probability and signal disc location was not observed, and (b) it was demonstrated that a search requirement is not a necessary condition for eliciting the main effects previously found.