the registration of stimuli below the level of awareness, particularly stimuli that are too weak (or too rapid) for an individual to consciously perceive them. There has been much debate about whether responses to subliminal stimuli actually occur and whether it is possible for subliminal commands or advertising messages to influence behavior. Experimental evidence indicates that subliminal commands may not directly affect behavior but may prime later responses (see subliminal priming). Compare supraliminal perception.