A strong test of exposure effects

A strong test of exposure effects was made by eliminating confounding demand characteristics through the use of a between-subject design. Each subject viewed novel stimuli at a single frequency level, and then rated them on several affective scales. Frequency of stimulus exposure was systematically varied across subjects. Stimuli were rated more positively with increasing exposure, despite the fact that subjects were unaware of any differences in exposure frequencies, and clearly unable to identify the experimental hypothesis. An awareness of the relationship between repeated exposure and affect was thus shown to be an unnecessary condition for the occurrence of exposure effects.