Three experiments with students from 7th and 8th grade were performed to investigate the effects of decorative pictures in learning as compared to instructional pictures. Pictures were considered as instructional, when they were primarily informative, and as decorative, when they were primarily aesthetically appealing. The experiments investigated, whether and to what extent decorative pictures affect the learner's distribution of attention, whether they have an effect on the affective and motivational state and whether they affect the learning outcomes. The first experiment indicated with eye-tracking methodology that decorative pictures receive only a bit initial attention as part of the learner's initial orientation and are largely ignored afterwards, which suggests that they have only a minor distracting effect if any. The second experiment showed that despite the small amount of attention they receive, decorative pictures seem to induce better mood, alertness and calmness with learners. The third experiment indicated that decorative pictures did not intensify students' situational interest, but reduced perceived difficulty of the learning material. Regarding outcomes of learning, decorative pictures were altogether neither harmful nor beneficial for learning. However, they moderated the beneficial effect of instructional pictures--in essence: the multimedia effect. The moderating effect was especially pronounced when learners had lower prior knowledge. The findings are discussed from the perspective of cognitive, affective and motivational psychology. Perspectives of further research are pointed out.