Eye tracking constitutes a valuable tool for the examination of human visual behavior since it provides objective measurements related to the performed visual strategies during the observation of any type of visual stimuli. Over the last decade, eye movement analysis contributed substantially to the better understanding of how visual attention processes work in different types of maps. Considering the clear need for the examination of map user reaction during the observation of realistic cartographic products (i.e. static maps, animated maps, interactive and multimedia maps), a critical amount of experimental studies were performed in order to study different aspects related to map reading process by the cartographic community. The foundation of these studies is based on theories and models that have been developed in similar research domains (i.e. psychology, neuroscience etc.), while the research outcomes that produced over these years can be used directly for the design of more effective and efficient maps. The aim of the present article is to summarize and present the current panorama of the existing eye tracking studies in cartographic research appeared over the last decade. Additionally, methodological contributions (including analysis tools) of cartographic society in the field of eye movement analysis are reported, while existing challenges and future perspectives are also discussed.

Eye tracking recordings could reveal the visual behavior for different cartographic visualization techniques, such as hill-shading, while at the same time eye tracking metrics (ETMs) can summarize the associated complexity levels in a concise and quantitative manner. In the present study, three different hill-shading methods, including: (i) the standard method based on ideal diffuse reflection, (ii) the Multidirectional Oblique- Weighted method – MDOW and (iii) the combination of a MDOW’s variation with standard hill-shading, are evaluated and ranked in terms of their perceived visual complexity. The performed examination is based on both eye tracking techniques and expert judgement procedures. A weighted combination of basic ETMs has been used, implemented by the Landscape Rating Index – LRI. The weights resulted from an experts’ judgement process where the opinions of experts in geoinformatics, cartography, geovisualization, experimental psychology, cognitive science, neuroscience and eye tracking were analyzed. Fifteen (15) individuals participated in an eye tracking experiment with hill-shading images produced by the three methods under evaluation, while 41 experts participated in an online questionnaire in order to collect all the analysis data. The final evaluation was based on the computation of three LRI models. The outcomes indicate that implementing hill-shading with more than one light sources results in similar perceptual behaviors, allowing for a seamless exploitation of the advantages of using multidirectional illumination.