One version of direct response priming requires automatization of the relevant associations but not awareness of the prime.

Priming is the influence of one event on performance during a second event. One type of priming is known as semantic priming because it biases interpretation of the subsequent stimulus. Another type, direct response priming, biases responding directly without semantic mediation. Research reviewed in this article indicates that two versions of the second type, direct response priming, can be distinguished. One version, explicit priming, requires awareness of the prime. The other version, associative response priming, occurs even if the prime is masked and not phenomenally visible. This version, which is attributed to associations relating specific sensory events to movements of particular muscles, is enabled only if the association has previously been automatized by brief practice in which the to-be-primed response is made to the stimulus that subsequently appears as the prime. Associative response priming can be explained by a simple stimulus-response interpretation; other varieties of priming are more theoretically challenging.