Intuitive visual representations of electromagnetic radiation and molecules

Understanding how learners interpret visual representations of invisible scientific phenomena is crucial for teaching and designing effective instructional materials. This study investigated which visualizations of infrared radiation, radiation absorption, and molecules are perceived as most intuitively comprehensible by students and adults. Grounded in dual process theories of cognition and cognitive load theory, we hypothesized that intuitive visualizations increase cognitive fluency, thereby reducing extraneous cognitive load. A total of <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"> <a:mrow> <a:mi>n</a:mi> <a:mo>=</a:mo> <a:mn>377</a:mn> </a:mrow> </a:math> students aged 14–15 and <c:math xmlns:c="http://www.w3.org/1998/Math/MathML" display="inline"> <c:mrow> <c:mi>n</c:mi> <c:mo>=</c:mo> <c:mn>1</c:mn> <c:mn>0</c:mn> <c:mn>0</c:mn> </c:mrow> </c:math> adults participated in an online survey, selecting the visualization they found most convincing for each of the scientific concepts. The visualizations were developed based on prior physics education research, and participants’ preferences were analyzed using Bayesian model comparison. Across all topics, certain visualizations—especially those developed in prior domain-specific research—were strongly preferred, suggesting that intuitive comprehensibility can be systematically supported through thoughtful visual design. Differences between student and adult preferences highlighted the role of prior knowledge and visual familiarity, as adults were clearer in their choices. The findings contribute to a systematic investigation of visual representations used in science education and science communication and offer practical guidance for developing intuitive visualizations in instructional contexts.