The article presents some results of an interdisciplinary study aimed at clarifying the conditions for the use of cardiometric and electrodermal indicators of human activity as a means of attesting to visual online content. To record personal reactions to selected visual objects, the authors use a range of tools, including computer cardiometers, portable eye trackers and polygraphs of various modifications. To achieve this goal, the authors conducted a multi-level test of Russian youth using current political symbols and images from online communities and other social media platforms. The results of the study prove the high efficiency of using cardio-oculometric detection combined with automatic recording of electrodermal activity to obtain reliable information about affective and rational-logical features of perception of visual online content. The study also extends the research understanding of the specifics of using this combination of diagnostic tools in different conditions.