In 1968, Robert Zajonc published one of the most replicated findings in social psychology: mere repeated exposure to a stimulus increases liking for it — independent of any conscious recognition or evaluation.

The Key Experiments

Zajonc exposed subjects to unfamiliar Chinese characters, nonsense words, and photographs of faces at varying frequencies. He then asked subjects to rate how much they liked each stimulus. The pattern was consistent: higher exposure frequency produced higher liking ratings, even when subjects had no conscious memory of seeing the stimulus before.

The Subliminal Version

In later studies, stimuli flashed too briefly for conscious recognition still produced liking increases — demonstrating the effect operates below conscious awareness.

Why It Matters

• Advertising: Brand awareness translates directly to preference — exposure is the mechanism
• Music: Songs become likable through repetition regardless of initial reaction
• Relationships: Physical proximity (dorm neighbors, office colleagues) predicts friendship — mere exposure drives liking
• Politics: Name recognition alone is a powerful electoral advantage

Reference:

Wikipedia: Mere-Exposure Effect

https://en.wikipedia.org/wiki/Mere-exposure_effect