A dataset record containing demonstration data for openseize, an open-source python software package for analyzing large EEG datasets from a variety of formats. Specifically, this record contains the following datasets: recording_001.edf A European data format+ file containing four channels of EEG data sampled at 5 KHz for 3775 seconds (~1.05 Hrs). The header of this file contains all the necessary metadata to interpret the data. annotations_001.txt A tab separated value file containing annotations for the file recording_001.edf. The first 6 lines of this file containing metadata concerning the experiment and can be ignored. The column data consists of the annotation number, the start date-stamp of the annotation, the stop date-stamp of the annotation, the time from the start of the recording in seconds, the channel the annotation was identified on, and the user defined annotation label. The annotation labels in this file denote three different behavioral states identified by a video recording. They are grooming, rest and exploring. Each state was measured for approximately 15 secs.