Janczyk, M. & Kunde, W.
Department of Psychology III, University of Würzburg, Würzburg, Germany
The psychological refractory period (PRP) paradigm is a well established tool to investigate the micro structure of dual-task performance within mental chronometry. Since its renaissance in the early 1990ies a vast amount of tasks has been reported to produce a PRP effect - ever since taken as an indicator for capacity limitations of the involved tasks. In fact, exceptions from the PRP effect have rarely (if ever) been reported and are controversial (extensive practice, ideomotor-compatible tasks, …), questioning the usefulness of this paradigm to ascribe capacity limitations to a given task. At first glance, reflexes may constitute a potential class of fully automated behavior, thus not susceptible to the PRP effect. However, the intensity and latency of the eye blink component of the startle reflex can also be modulated by, for example, pre-pulses or emotional background content. In the first experiment, we show that a standard PRP effect can be obtained when participants are to blink intentionally as a response to an imperative stimulus. In a second experiment, we elicited the very same response with an air puff. Here, no signs of a PRP effect were obtained, reinforcing the claim that exceptions from the PRP effect indeed exist.