Multifractal Detrended Fluctuation Analysis of Eye-Tracking Data

In this contribution, we perform detrended fluctuation analysis on eye movement data obtained using an eye tracker with different experimentation subjects performing a set of distinct cognitive tasks. We define three different paradigms: spotting differences among two similar pictures, answering questions in a multiple choice questionnaire, and performing the Trail Making Test to measure subject attention. Using multifractal detrended fluctuation analysis (MDFA) we evaluate the Hurst exponent, the multifractal spectrum and correlation coefficient of the subjects' eye movements under these different cognitive tasks. Under these paradigms, the MDFA presents a characteristic f(alpha) spectrum, showing that the organizational structure of the data reflects the ocular activities of the subjects under the different tasks. An interpretation of the MDFA spectrum features provides insights on the internal cognitive strategies deployed in each of the paradigms.