  Electroencephalography (EEG) signals recordings when people reading natural
languages are commonly used as a cognitive method to interpret human language
understanding in neuroscience and psycholinguistics. Previous studies have
demonstrated that the human fixation and activation in word reading associated
with some brain regions, but it is not clear when and how to measure the brain
dynamics across time and frequency domains. In this study, we propose the first
analysis of event-related brain potentials (ERPs), and event-related spectral
perturbations (ERSPs) on benchmark datasets which consist of sentence-level
simultaneous EEG and related eye-tracking recorded from human natural reading
experiment tasks. Our results showed peaks evoked at around 162 ms after the
stimulus (starting to read each sentence) in the occipital area, indicating the
brain retriving lexical and semantic visual information processing approaching
200 ms from the sentence onset. Furthermore, the occipital ERP around 200ms
presents negative power and positive power in short and long reaction times. In
addition, the occipital ERSP around 200ms demonstrated increased high gamma and
decreased low beta and low gamma power, relative to the baseline. Our results
implied that most of the semantic-perception responses occurred around the
200ms in alpha, beta and gamma bands of EEG signals. Our findings also provide
potential impacts on promoting cognitive natural language processing models
evaluation from EEG dynamics.
