Disclosed herein is a technique for observing the insular cortex activity by using electroencephalograms. A method for sampling cerebral insular cortex activity includes: recording electroencephalograms (EEGs) provided by a plurality of EEG electrodes； creating a three-dimensional model in the form of a mesh in which a subject's brain is decomposed into a plurality of sites according to the subject's brain structure and positioning the plurality of EEG electrodes by reference to an image representing the subject's brain and head structure； creating a forward model by modeling a correlation between the activities of the respective brain sites of the three-dimensional model and an electroencephalogram distribution of the positioned EEG electrodes； and associating, by reference to information about a region of interest measured by functional magnetic resonance imaging (fMRI) and the forward model, data about the electroencephalograms recorded with the cerebral activity of the region of interest.
