The mere exposure effect -- increased liking for a stimulus following repeated exposure to that stimulus -- is one of the most well-established phenomena in social psychology. Mere exposure effects have numerous real-world applications, enhancing attitudes regarding members of unfamiliar ethnic and racial groups, diminishing negative reactions to feared stimuli (for example, spiders, snakes), and helping shape both aesthetic preferences and food preferences in a variety of situations and contexts. Although the existence of the mere exposure effect is well-established, the processes underlying the effect remain elusive. Given that exposure effects can persist undiminished for extended periods (sometimes several weeks or longer) following stimulus exposures, a key component of the mere exposure effect may be the formation of a mental image of the merely exposed stimulus which is encoded in long-term memory and retrieved at a later date. The objectives of this program of research are to explore the psychological and neurological processes that underlie the exposure effect by examining the role of mental imagery in shaping responses to merely exposed visual stimuli. Experiments are designed to determine whether manipulating various features of mental images of merely exposed stimuli (for example, objects, animals, photographs of people) alter the effect in meaningful ways. Separate sets of experiments test the hypotheses that (1) manipulations that have been shown to alter the latency of mental imagery judgments produce parallel changes in the latency of liking ratings of merely exposed stimuli; and (2) functional magnetic resonance imaging (fMRI) assessed cortical activation patterns produced during evaluative ratings of merely-exposed stimuli are consistent with those predicted by the mental imagery framework. By delineating the processes that underlie the mere exposure effect this program of research will set the stage for continued application of mere exposure methods and findings to real-world problems and issues such as fear acquisition and reduction, attitude formation and change, and stereotype- and prejudice-reduction.
