DEPARTURE FROM THE ONSET ONSET RULE

Using a signal-detection task, the generality of Turvey's (1973) onset -onset rule was tested in our experiments. After seeing, in succession , (1) one or two letters (target display), (2) a multiletter detection display, and (3) a mask display, subjects decided whether or not the letter or letters in the target display reappeared in the succeeding d etection display at different levels of detection-display duration in various situations. The subjects' sensitivity was inconsistent with th e onset-onset rule. More specifically, sensitivity increased with incr eases in display duration within a fixed stimulus onset asynchrony of 150 msec. Display duration, however, had no effect on response bias. N or was there any interaction between display duration and display size in terms of either sensitivity or response bias. The more complicated relationship between display duration and display size does not inval idate the departure from the onset-onset rule.