EEG data closed and open eyes: OpenBCI Cyton and EEG Prototype

The participant group included a total of seven vol-unteers (males) who agreed to participate in theresearch. Their mean age was 29.67 (range 24–56).The participants indicated that they do not havehearing or visual impairments. Participation was vol-untary and informed consent was obtained for eachparticipant in order to employ their EEG data in ourstudy. We captured the brain activity of the subjects with the proposed EEG prototype (see [1]) and the OpenBCI Cyton board. Gold cup electrodes were placed in accordance with the 10–20 international system for electrode placement andattached to the subjects scalp using a conductive paste. Electrode-skin impedances were checked to bebelow 15 kΩ at all electrodes. Several studies have proved that the alpha rhythm predominates in the occipital area of the brain when subjects remain with their eyes closed and it is reduced when visualstimulation takes place. In accordance with these works, the input channel of the prototype was located in the O2 position. Moreover, to reduce the setup time and improve the EEG signal quality, the reference and ground electrodes were placed inthe FP2 and A1 positions, respectively, where the absence of hair facilitates its placement. All the experiments were conducted in a sound-attenuated and controlled environment. Participants were seated in a comfortable chair and asked to be relaxed and focused on the task, trying to avoid any distraction or external stimulus. Experiments were composed of 2 tasks: the first one, 60 s of oE and the second, 60 s of cE. Each task was separated by a pause of at least 3 s to ensure the participant is rested before a new task. In order to simulate a real-life situation, the subject could move his gaze freely during the eye-open tasks, without the need to keep it at a fixed point. The procedure was conveniently explained in advance allowing the participants to feel comfortable and familiar with the test environment. Possible artifacts were minimized by asking them not to speak, move or blink (or atleast as little as possible) throughout the oE task. A total of 10 tasks (i.e. 10 min) were recorded for each participant, which corresponds to five tasks of oE and five tasks of cE. Data is organized in a folder for each subject (S1, S2, S3, etc.). Inside each subject folder we find two different folders: PP: which contains the recordings captured with the proposed prototype. OPB: which contains the recordings captured with the Cyton board. Inside each of these folders we will find 10 files: 5 corresponding to open eyes and closed eyes. The name of these files follows the structure: Closed eyes: cerrados[# recording]_[# subject].csv Open eyes: abiertos[# recording]_[# subject].csv Each .csv file contains 2 data columns: timestamp and O2 channel. [1] Laport, F., Dapena, A., Castro, P. M., Vazquez-Araujo, F. J., & Iglesia, D. (2020). A prototype of EEG system for IoT. International journal of neural systems, 30(07), 2050018. DOI: https://doi.org/10.1142/S012906572050018本研究的受试群体共包含7名男性志愿者，所有受试者均同意参与本项研究。受试者平均年龄为29.67岁，年龄区间为24~56岁，自述无听力或视力障碍。本次研究采用自愿参与原则，且已为每名受试者获取知情同意，以将其脑电图（electroencephalogram，EEG）数据用于本研究。 我们使用自研的脑电图原型系统（详见参考文献[1]）与OpenBCI Cyton采集板采集受试者的脑电活动。按照10-20国际电极放置系统摆放金杯电极，并使用导电膏将电极固定于受试者头皮。经检测，所有电极的电极-皮肤阻抗均低于15千欧（kΩ）。 已有多项研究证实，当受试者保持闭眼状态时，大脑枕叶区域以α节律（alpha rhythm）为主；而当存在视觉刺激时，α节律活动会减弱。基于上述研究结论，本次原型系统的输入通道设置于O2点位。此外，为缩短准备时长并提升脑电信号质量，参考电极与接地电极分别放置于FP2与A1点位，该区域无毛发覆盖，便于电极安装。 所有实验均在隔音且环境可控的实验环境内开展。受试者舒适端坐于座椅中，需保持放松状态并专注于实验任务，尽量避免分心或受到外界刺激。实验包含两项任务：第一项为睁眼任务（后文简称oE），时长60秒；第二项为闭眼任务（后文简称cE），时长同样为60秒。两项任务之间设置至少3秒的休息间隔，以确保受试者在进入下一项任务前得到充分休息。 为模拟真实生活场景，受试者在睁眼任务中可自由移动视线，无需固定注视某一点。实验流程已于事前向受试者详细讲解，以帮助其熟悉实验环境并缓解紧张情绪。为尽可能减少伪迹干扰，要求受试者在睁眼任务全程尽量不说话、不移动身体或眨眼（若无法完全避免则需尽量减少次数）。每名受试者共采集10组任务数据（总时长10分钟），包含5组睁眼任务与5组闭眼任务。 数据按受试者分文件夹存储（文件夹命名格式为S1、S2、S3等）。每个受试者文件夹内包含两个子文件夹： PP：存储使用自研原型系统采集的脑电记录数据。 OPB：存储使用Cyton采集板采集的脑电记录数据。 上述两个子文件夹内均包含10个数据文件，对应5组睁眼任务与5组闭眼任务。文件命名规则如下： 闭眼任务：cerrados[# recording]_[# subject].csv 睁眼任务：abiertos[# recording]_[# subject].csv 每个.csv文件包含两列数据：时间戳（timestamp）与O2通道脑电数据。 [1] Laport, F., Dapena, A., Castro, P. M., Vazquez-Araujo, F. J., & Iglesia, D. (2020). 面向物联网的脑电图系统原型. 国际神经系统杂志, 30(07), 2050018. DOI: https://doi.org/10.1142/S012906572050018