Signals were acquired, processed, and analyzed using the co-registration technique of electroencephalography (EEG) and eye tracking (ET) in a reading comprehension study applied to a population of university students. EEG and ET data were synchronized, obtaining potential related to the first fixation (FRP) in search of the underlying processes of reading in this population. The study was conducted in two periods: before and after training applied to the population, which was divided into two groups: control and experimental, receiving different training. The main stimuli is presented as a lexicality challenge: word or pseudoword in three different contexts: familiar, less familiar and neutral. This word is presented in the center of the screen and the EEG is segmented in epochs using the first fixation mark. Preliminary FRP results show significant differences in N400 component related to the triple interactions: period-group-context and group-context-lexicality. These findings lay the groundwork for future research and methodological improvements, making it possible to measure reading ability through the co-registration technique.