{
  "Name": "Liu2020 – BETA SSVEP benchmark dataset",
  "BIDSVersion": "1.9.0",
  "HEDVersion": "8.4.0",
  "DatasetType": "derivative",
  "License": "Non-commercial research use",
  "Authors": [
    "Bingchuan Liu",
    "Xiaoshan Huang",
    "Yijun Wang",
    "Xiaogang Chen",
    "Xiaorong Gao"
  ],
  "Funding": [
    "National Key Research and Development Program of China (No. 2017YFB1002505)",
    "Strategic Priority Research Program of Chinese Academy of Sciences (No. XDB32040200)",
    "Key Research and Development Program of Guangdong Province (No. 2018B030339001)",
    "National Natural Science Foundation of China (Grant No. 61431007)"
  ],
  "EthicsApprovals": [
    "Ethics Committee of Tsinghua University, No. 20190002"
  ],
  "ReferencesAndLinks": [
    "http://bci.med.tsinghua.edu.cn/upload/liubingchuan/"
  ],
  "GeneratedBy": [
    {
      "CodeURL": "https://github.com/NeuroTechX/moabb",
      "Name": "moabb",
      "Description": "Mother of All BCI Benchmarks",
      "Version": "1.4.3"
    }
  ],
  "SourceDatasets": [
    {
      "DOI": "10.3389/fnins.2020.00627",
      "URL": "http://bci.med.tsinghua.edu.cn/upload/liubingchuan/"
    }
  ],
  "Keywords": [
    "SSVEP",
    "BCI",
    "EEG",
    "benchmark",
    "JFPM"
  ],
  "PublicationYear": 2020,
  "ExperimentName": "Liu2020",
  "Description": "BETA SSVEP benchmark dataset.\n\n\nDataset summary:\n\n#Subj     70\n#Chan     64\n#Classes     40\n#Trials / class      4\nTrials length    3 s\nFreq 250 Hz\n#Sessions      1\n\n\nParticipants:\n\n- Population: healthy\n- Age: 25.14 (range: 9-64) years\n- BCI experience: mixed\n\n\nEquipment:\n\n- Amplifier: Synamps2 (Neuroscan)\n- Montage: standard_1005\n- Reference: Cz\n\n\nPreprocessing:\n\n- Data state: epoched\n\n\nData Access:\n\n- DOI: 10.3389/fnins.2020.00627\n- Data URL: http://bci.med.tsinghua.edu.cn/upload/liubingchuan/\n- Repository: Tsinghua BCI Lab\n\n\nExperimental Protocol:\n\n- Paradigm: ssvep\n- Task type: cued-spelling\n- Feedback: visual\n- Stimulus: JFPM visual flicker\n\nDataset from [1]_.\n\nThe BETA database contains 64-channel EEG recordings from 70 healthy\nsubjects (42 males, 28 females, aged 9-64 years, mean age 25.14) performing\na 40-target cued-spelling SSVEP-BCI task. Unlike Wang2016 which was collected\nin a shielded room, BETA was recorded in a normal classroom, providing a more\nrealistic BCI benchmark.\n\nStimuli used joint frequency and phase modulation (JFPM) with 40 targets\narranged in a 5x8 QWERTY virtual keyboard. Frequencies ranged from 8.0 to\n15.8 Hz (0.2 Hz step) with initial phases from 0 to 19.5*pi (0.5*pi step).\n\nEach subject completed 4 blocks of 40 trials. Stimulation duration was 2 s\nfor subjects S1-S15 (experienced) and 3 s for subjects S16-S70 (naive), plus\na 0.5 s visual cue. EEG was recorded at 1000 Hz with a Synamps2 system\n(Neuroscan) using 64 channels in the international 10-10 system, then\ndownsampled to 250 Hz.\n\nData are stored as 4D matrices [64, 750, 4, 40] corresponding to\n[channels, time points, block index, target index]. Each epoch is 3 s\n(750 samples at 250 Hz).\n\nWarnings\n--------\nLike Wang2016, this dataset includes channels 'CB1' and 'CB2' which are\nnot part of the standard 10-20 montage. They are treated as standard EEG\nchannels with ``on_missing=\"ignore\"`` for montage setting.\n\nThe data is downloaded from the Tsinghua BCI Lab server in tar.gz archives\ngrouped by 10 subjects each. The download may be slow depending on server\navailability.\n\nReferences\n----------\n.. [1] B. Liu, X. Huang, Y. Wang, X. Chen, and X. Gao, \"BETA: A Large\nBenchmark Database Toward SSVEP-BCI Application,\" Frontiers in\nNeuroscience, vol. 14, p. 627, 2020.\nDOI: 10.3389/fnins.2020.00627",
  "DatasetDOI": "10.82901/nemar.nm000129",
  "Version": "1.0.2"
}