The mediating role of learning in the relationship between repeated exposure and affect was explored and supported in three experiments involving a total of 229 undergraduate participants. It was found that both learning and affect measures behaved in essentially the same way as a function of exposure duration (Experiments 1 and 3), serial position (Experiments 1 and 2), rating delay (Experiment 1) and stimulus properties (Experiment 1). These results suggest learning may be intrinsically rewarding and clarify one of the mechanisms involved in the relationship between exposure frequency and affect, extending Berlyne's two-factor theory of the effects of stimulus familiarity.