In the psychology of perception and motor control, the term response priming denotes a special form of priming. Generally, priming effects take place whenever a response to a target stimulus is influenced by a prime stimulus presented at an earlier time. The distinctive feature of response priming is that prime and target are presented in quick succession (typically, less than 100 milliseconds apart) and are coupled to identical or alternative motor responses. When a speeded motor response is performed to classify the target stimulus, a prime immediately preceding the target can thus induce response conflicts when assigned to a different response as the target. These response conflicts have observable effects on motor behavior, leading to priming effects, e.g., in response times and error rates. A special property of response priming is its independence from visual awareness of the prime.
In 1962, Fehrer and Raab reported experiments where participants were required to press a single key as quickly as possible upon presentation of a visual target stimulus. The visibility of the target was strongly reduced by so-called metacontrast masking (see below). The authors found that the response times were independent of the subjective visibility of the target, i.e., responses to well-visible targets were just as fast as those to nearly invisible targets (Fehrer-Raab effect). The term response priming was first employed by Rosenbaum and Kornblum with respect to an experimental paradigm where different aspects of motor responses were primed by visual stimuli. The modern procedure of response priming was developed in the 1980s and 1990s by Peter Wolff, Werner Klotz, Ulrich Ansorge, and Odmar Neumann at the University of Bielefeld, Germany. The paradigm was developed further in the 1990s by a research team led by Dirk Vorberg at the University of Braunschweig, Germany.
Typical time course of a trial in a response priming paradigm. Here, the participant responds as quickly as possible to the shape of the target stimulus (diamond or square) by pressing the assigned response key. Shortly before, a prime is presented (also a diamond or square) that influences the response to the target. The time interval between prime onset and target onset is called the "stimulus-onset asynchrony" (SOA). In many response priming experiments, the target also serves to visually mask the prime. Therefore, a second task is often employed where participants are asked to identify the masked prime. b) Prime and target are consistent when assigned to the same response, and inconsistent when assigned to different responses. c) The visibility of the prime can be strongly influenced by masking effects from the target.