Motor and Speech Imagery EEG Dataset

Overview and MethodologyThis dataset contains motor imagery (MI) and speech imagery (SI) electroencephalogram (EEG) data recorded from 5 healthy subjects with a mean age of 24.4 years. MI involves the subject imagining movements in their limbs, whereas SI involves the subject imagining speaking words in their mind (thought-speech). The data was recorded using the BioSemi ActiveTwo electroencephalogram (EEG) recording equipment, at a sampling frequency of 2.048kHz. 24 channels of EEG data from the 10-20 system are available in the dataset. Four classes of data were recorded for each of the MI and SI paradigms. In the case of MI, left-hand, right-hand, legs and tongue MI tasks were recorded, and in the case of SI, the words, ‘left’, ‘right’, ‘up’ and ‘down’ were recorded. Data for the idle state, when the subject is mentally relaxed and not executing any tasks, was also recorded.Forty trials were recorded for each of the classes. These trials were recorded over four runs, with two runs being used to record MI trials, and two to record SI trials. The runs were interleaved, meaning that the first and third runs were used to record MI, and the second and fourth runs were used to record SI trials. During each run, twenty trials for each class in the paradigm were recorded. These trials were randomly ordered. Note that during each run, twenty trials of the idle state were also recorded. This means that in this database there are actually eighty idle state trials, with forty being recorded during MI runs and forty being recorded during SI runs.Subjects were guided through the data recording runs by a graphical user interface which issued instructions to them. At the start of a run, subjects are given one minute to settle down before the cued trials began. During a trial, a fixation cross first appears on-screen, indicating to the subject to remain relaxed but aware that the next trial will soon begin. After 2s a cue appears on-screen for 1.25s, indicating the particular task the subject should execute. The subject starts executing the task as soon as they see the cue, and continue even when it has disappeared, until the fixation cross appears again. The cues consist of a left-facing arrow (for left-hand MI or ‘left’ SI), a right-facing arrow (for right-hand MI or ‘right’ SI), an upward facing (for tongue MI or ‘up’ SI) and a downward facing arrow (for legs MI or ‘down’ SI). Each trial lasted 4 seconds. Between each run, subjects were given a 3–5-minute break. The data was re-referenced using channel Cz and then mean-centered it. The data was also passed through an anti-aliasing filter and down-sampled to 1kHz before being stored in .mat files for the data repository. The anti-aliasing filter was a low-pass filter with a cutoff frequency of 500Hz, implemented using the lowpass function in MATLAB, which produces a 60dB attenuation above the cutoff and automatically compensates for filter-induced delays.FilesThe dataset consists of 10 MAT-files, named X_Subject_Y.mat, where X is the acronym denoting the brain imagery type, either MI for motor imagery data or SI for speech imagery data, and Z is the subject number. Each file contains the trials for each run in the structure variables ‘run_1’ and ‘run_2’. Within each run structure there are two variables:‘EEG_Data’, a matrix containing the EEG data formatted as: [number of trials x channels x data samples]. The number of data samples is 4000 since the length of each trial was 4s, sampled at 1kHz. The relationship between the EEG channels and the channel number in the second dimension of this matrix is documented in the table stored within the ‘ChannelLocations.mat’ file, which is included with the dataset;‘labels’, a vector indicating which cue was issued, with the following numbers being used to represent the different cues: 1 – Right, 2 – Left, 3 – Up, 4 – Down, 5 – Idle, 6 – Fixation Cross.Acknowledgements The authors acknowledge that data collection for this project was funded through the project: “Setting up of transdisciplinary research and knowledge exchange (TRAKE) complex at the University of Malta (ERDF.01.124)”, which is being co-financed through the European Union through the European Regional Development Fund 2014–2020. The data was recorded by the Centre for Biomedical Cybernetics at the University of Malta.

概述与方法本数据集包含由5名平均年龄为24.4岁的健康受试者记录的脑电（EEG）数据，数据类型包括运动想象（MI）和言语想象（SI）。运动想象涉及受试者对其肢体运动的想象，而言语想象则涉及受试者心中言语的想象（思维言语）。数据使用BioSemi ActiveTwo脑电记录设备记录，采样频率为2.048kHz。数据集中包含了10-20系统下的24个通道的EEG数据。对于MI和SI范式，分别记录了四种数据类别。在MI的情况下，记录了左手、右手、腿部和舌头的MI任务；在SI的情况下，记录了‘left’（左）、‘right’（右）、‘up’（上）和‘down’（下）等词语。此外，还记录了受试者处于闲置状态（精神放松，不执行任何任务）时的数据。每个类别均记录了40次试验。这些试验在四次运行中记录，其中两次用于记录MI试验，另外两次用于记录SI试验。运行是交错进行的，即第一和第三次运行用于记录MI，第二和第四次运行用于记录SI试验。在每次运行中，每个类别的试验均为20次，这些试验是随机排序的。请注意，在每次运行中，还记录了20次闲置状态的试验。这意味着在此数据库中实际上有80次闲置状态的试验，其中40次在MI运行期间记录，40次在SI运行期间记录。受试者在图形用户界面的引导下完成数据记录运行，界面向他们发出指令。在运行开始时，受试者有1分钟的时间平静下来，然后开始提示试验。在试验过程中，屏幕上首先出现一个注视点，提示受试者保持放松，同时意识到下一个试验即将开始。2秒后，屏幕上出现一个持续1.25秒的提示，指示受试者应执行的任务。受试者看到提示后立即开始执行任务，即使在提示消失后也要继续，直到再次出现注视点。提示包括指向左边的箭头（用于左手MI或‘left’ SI）、指向右边的箭头（用于右手MI或‘right’ SI）、向上的箭头（用于舌头MI或‘up’ SI）和向下的箭头（用于腿部MI或‘down’ SI）。每个试验持续4秒。在每次运行之间，受试者会得到3-5分钟的休息。数据使用通道Cz进行重参考，并进行了均值中心化。数据还通过了抗混叠滤波器，并下采样到1kHz，然后存储在.mat文件中，以供数据存储库使用。抗混叠滤波器是一个截止频率为500Hz的低通滤波器，使用MATLAB中的低通函数实现，该函数在截止频率以上产生60dB的衰减，并自动补偿滤波器引起的延迟。文件本数据集包含10个MAT文件，命名为X_Subject_Y.mat，其中X是表示大脑影像类型的缩写，可以是MI（运动想象数据）或SI（言语想象数据），而Y是受试者编号。每个文件包含每个运行的试验，存储在结构变量‘run_1’和‘run_2’中。在每个运行结构中，有两个变量：‘EEG_Data’，一个包含EEG数据的矩阵，格式为：[试验次数 x 通道 x 数据样本]。数据样本的数量为4000，因为每个试验的长度为4秒，以1kHz的频率采样。EEG通道与矩阵第二维中的通道编号之间的关系在包含在数据集中的‘ChannelLocations.mat’文件中有记录；‘labels’，一个向量，指示发出的提示，以下数字用于表示不同的提示：1 – 右，2 – 左，3 – 上，4 – 下，5 – 闲置，6 – 注视点。致谢作者承认，该项目数据收集得到“在马耳他大学建立跨学科研究和知识交流（TRAKE）复合体”（ERDF.01.124）项目的资助，该项目由欧洲联盟通过欧洲区域发展基金2014-2020年共同资助。数据由马耳他大学的生物医学控制论中心记录。