The study compared student conceptual knowledge gains in chemistry and physics when taught with and without visualizations. It found no significant differences in overall learning gains between the two groups. For physics classes, male students saw slightly higher gains when using visualizations compared to females. The researchers concluded that while visualizations did not decrease learning, their effectiveness was not clearly proven and excessive claims about their benefits should be avoided. They plan to conduct a follow up study with more focus on the types and uses of visualizations.