AND

Subjects saw 16 consonants presented serially at a.5-second rate. Then following a.7-second blank interval, a test consonant was presented which subjects judged to be present or not in the preceding list. A tapping speed accuracy trade-off method was employed in which subjects pressed both "yes " and "no " keys every.4 seconds, beginning during the blank interval. Both keys are pressed simultaneously at first in this method, but as soon as possible the chosen response is to lead the other by a time interval that reflects confidence in the decision. Memory strength in storage declined over a 6-second interval containing 12 items, but priming of retrieval dynamics was found only for the last item in the memory set. Active (primary) memory under these conditions appears to be limited to the very last thought. Any perturbation i behavior that is con-tingent upon some event and lasts for only a few seconds after that event may be called short-term memory. But calling different perturbations by the same name does not mean they result from the same underlying memory trace. The present paper is con-cerned with deciding whether two types of short-term perturbations, item strength and priming, result from the same underlying trace or different races. The method used is to determine whether the forgetting dynamics of these two perturbations are the same or different. In brief, the question is whether the two perturbations disappear after the learning event at the same or dif