According to Myers (2006), the mere exposure effect refers to the psychological phenomenon in which our liking or disliking of a certain stimulus (faces, music, etc.) increases or decreases, respectively, with repeated exposure. In other words, familiarity increases liking or decreases disliking. You can imagine that advertisers take this information into account.
One study wanted to test this effect by giving a group of male subjects a taste of four types of tropical fruit juices that were unfamiliar to them. Each participant tried each juice 20, 10, 5, or 0 times. They were then asked to choose which one they liked best. The subjects chose as favorites those they had tried the most. Even more interesting, researchers suggest that this effect plays a role in the acquisition of preferences for certain foods ().
Sources: Myers, D. (2006), Psychology 7th edition. Panamericana Medical Editorial:Madrid
Pliner, P. (1982), The Effects of Mere Exposure on Liking for Edible Substances
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