Cognitive load measurement during navigation and information retrieval in digital text

Abstract

Interaction with digital text permeates practically all types of educational, professional and leisure activities of modern life. The effective working with digital instructions and materials determines the success in solving a number of real problems. At the same time, the negative impact of overly complex digital environments on learning outcomes, work efficiency, and subjective well-being has been proven in numerous empirical studies. In this work, an attempt is made to study the navigational characteristics of a digital text that are significant for solving practical problems from the standpoint of the Cognitive Load Theory. A total of 20 subjects (13F; 7M) took part in the experiment with intra-individual plan and 2x2 factorial design. Information retrieval was considered as a task, and the navigation characteristics of the text were varied under controlled experimental conditions in order to determine the optimal combination of navigational cues. Digital text environments with different navigation characteristics were designed. The indicators of oculomotor activity and performance data were analysed to determine the conditions causing the greatest excess cognitive load. A computational approach was applied to assess the relative effectiveness of conditions. It was found that information search in digital environments with less navigational cues provoke increase in scan-path complexity, searching time and number of fixations. These observations support the general hypothesis of this study, according to which a lack of navigation cues affect directly on the cognitive load growth during information search in digital texts.