NM000127: eeg dataset, 40 subjects#

Kim2025 – 40-class beta-range SSVEP speller dataset

Access recordings and metadata through EEGDash.

Citation: Heegyu Kim, Kyungho Won, Minkyu Ahn, Sung Chan Jun (2019). Kim2025 – 40-class beta-range SSVEP speller dataset.

Modality: eeg Subjects: 40 Recordings: 240 License: CC BY 4.0 Source: nemar

Metadata: Complete (90%)

Quickstart#

Install

pip install eegdash

Access the data

from eegdash.dataset import NM000127

dataset = NM000127(cache_dir="./data")
# Get the raw object of the first recording
raw = dataset.datasets[0].raw
print(raw.info)

Filter by subject

dataset = NM000127(cache_dir="./data", subject="01")

Advanced query

dataset = NM000127(
    cache_dir="./data",
    query={"subject": {"$in": ["01", "02"]}},
)

Iterate recordings

for rec in dataset:
    print(rec.subject, rec.raw.info['sfreq'])

If you use this dataset in your research, please cite the original authors.

BibTeX

@dataset{nm000127,
  title = {Kim2025 – 40-class beta-range SSVEP speller dataset},
  author = {Heegyu Kim and Kyungho Won and Minkyu Ahn and Sung Chan Jun},
}

About This Dataset#

40-class beta-range SSVEP speller dataset

40-class beta-range SSVEP speller dataset.

Dataset Overview

  • Code: Kim2025BetaRange

  • Paradigm: ssvep

  • DOI: 10.1038/s41597-025-06032-2

View full README

40-class beta-range SSVEP speller dataset

40-class beta-range SSVEP speller dataset.

Dataset Overview

  • Code: Kim2025BetaRange

  • Paradigm: ssvep

  • DOI: 10.1038/s41597-025-06032-2

  • Subjects: 40

  • Sessions per subject: 6

  • Events: 14=1, 15=2, 16=3, 17=4, 18=5, 19=6, 20=7, 21=8, 14.2=9, 15.2=10, 16.2=11, 17.2=12, 18.2=13, 19.2=14, 20.2=15, 21.2=16, 14.4=17, 15.4=18, 16.4=19, 17.4=20, 18.4=21, 19.4=22, 20.4=23, 21.4=24, 14.6=25, 15.6=26, 16.6=27, 17.6=28, 18.6=29, 19.6=30, 20.6=31, 21.6=32, 14.8=33, 15.8=34, 16.8=35, 17.8=36, 18.8=37, 19.8=38, 20.8=39, 21.8=40

  • Trial interval: [0.0, 5.0] s

  • File format: MAT

Acquisition

  • Sampling rate: 1024.0 Hz

  • Number of channels: 31

  • Channel types: eeg=31, misc=2

  • Montage: standard_1005

  • Hardware: BioSemi ActiveTwo

  • Software: OpenViBE

  • Reference: CMS/DRL

  • Ground: CMS/DRL near Pz

  • Sensor type: active

  • Line frequency: 60.0 Hz

  • Impedance threshold: 5 kOhm

  • Cap manufacturer: BioSemi

  • Electrode type: wet

  • Electrode material: Ag/AgCl

Participants

  • Number of subjects: 40

  • Health status: healthy

  • Age: mean=22.8, std=3.34, min=20, max=35

  • Gender distribution: male=25, female=15

  • BCI experience: 3 of 40 had prior SSVEP-BCI experience

Experimental Protocol

  • Paradigm: ssvep

  • Task type: speller

  • Number of classes: 40

  • Class labels: 14, 15, 16, 17, 18, 19, 20, 21, 14.2, 15.2, 16.2, 17.2, 18.2, 19.2, 20.2, 21.2, 14.4, 15.4, 16.4, 17.4, 18.4, 19.4, 20.4, 21.4, 14.6, 15.6, 16.6, 17.6, 18.6, 19.6, 20.6, 21.6, 14.8, 15.8, 16.8, 17.8, 18.8, 19.8, 20.8, 21.8

  • Trial duration: 5.0 s

  • Feedback type: none

  • Stimulus type: JFPM visual flicker

  • Stimulus modalities: visual

  • Primary modality: visual

  • Synchronicity: synchronous

  • Mode: offline

  • Training/test split: True

HED Event Annotations

Schema: HED 8.4.0 | Browse: https://www.hedtags.org/hed-schema-browser

14
     ├─ Sensory-event
     ├─ Experimental-stimulus
     ├─ Visual-presentation
     └─ Label/14

15
     ├─ Sensory-event
     ├─ Experimental-stimulus
     ├─ Visual-presentation
     └─ Label/15

16
     ├─ Sensory-event
     ├─ Experimental-stimulus
     ├─ Visual-presentation
     └─ Label/16

17
     ├─ Sensory-event
     ├─ Experimental-stimulus
     ├─ Visual-presentation
     └─ Label/17

18
     ├─ Sensory-event
     ├─ Experimental-stimulus
     ├─ Visual-presentation
     └─ Label/18

19
     ├─ Sensory-event
     ├─ Experimental-stimulus
     ├─ Visual-presentation
     └─ Label/19

20
     ├─ Sensory-event
     ├─ Experimental-stimulus
     ├─ Visual-presentation
     └─ Label/20

21
     ├─ Sensory-event
     ├─ Experimental-stimulus
     ├─ Visual-presentation
     └─ Label/21

14.2
     ├─ Sensory-event
     ├─ Experimental-stimulus
     ├─ Visual-presentation
     └─ Label/14_2

15.2
     ├─ Sensory-event
     ├─ Experimental-stimulus
     ├─ Visual-presentation
     └─ Label/15_2

16.2
     ├─ Sensory-event
     ├─ Experimental-stimulus
     ├─ Visual-presentation
     └─ Label/16_2

17.2
     ├─ Sensory-event
     ├─ Experimental-stimulus
     ├─ Visual-presentation
     └─ Label/17_2

18.2
     ├─ Sensory-event
     ├─ Experimental-stimulus
     ├─ Visual-presentation
     └─ Label/18_2

19.2
     ├─ Sensory-event
     ├─ Experimental-stimulus
     ├─ Visual-presentation
     └─ Label/19_2

20.2
     ├─ Sensory-event
     ├─ Experimental-stimulus
     ├─ Visual-presentation
     └─ Label/20_2

21.2
     ├─ Sensory-event
     ├─ Experimental-stimulus
     ├─ Visual-presentation
     └─ Label/21_2

14.4
     ├─ Sensory-event
     ├─ Experimental-stimulus
     ├─ Visual-presentation
     └─ Label/14_4

15.4
     ├─ Sensory-event
     ├─ Experimental-stimulus
     ├─ Visual-presentation
     └─ Label/15_4

16.4
     ├─ Sensory-event
     ├─ Experimental-stimulus
     ├─ Visual-presentation
     └─ Label/16_4

17.4
     ├─ Sensory-event
     ├─ Experimental-stimulus
     ├─ Visual-presentation
     └─ Label/17_4

18.4
     ├─ Sensory-event
     ├─ Experimental-stimulus
     ├─ Visual-presentation
     └─ Label/18_4

19.4
     ├─ Sensory-event
     ├─ Experimental-stimulus
     ├─ Visual-presentation
     └─ Label/19_4

20.4
     ├─ Sensory-event
     ├─ Experimental-stimulus
     ├─ Visual-presentation
     └─ Label/20_4

21.4
     ├─ Sensory-event
     ├─ Experimental-stimulus
     ├─ Visual-presentation
     └─ Label/21_4

14.6
     ├─ Sensory-event
     ├─ Experimental-stimulus
     ├─ Visual-presentation
     └─ Label/14_6

15.6
     ├─ Sensory-event
     ├─ Experimental-stimulus
     ├─ Visual-presentation
     └─ Label/15_6

16.6
     ├─ Sensory-event
     ├─ Experimental-stimulus
     ├─ Visual-presentation
     └─ Label/16_6

17.6
     ├─ Sensory-event
     ├─ Experimental-stimulus
     ├─ Visual-presentation
     └─ Label/17_6

18.6
     ├─ Sensory-event
     ├─ Experimental-stimulus
     ├─ Visual-presentation
     └─ Label/18_6

19.6
     ├─ Sensory-event
     ├─ Experimental-stimulus
     ├─ Visual-presentation
     └─ Label/19_6

20.6
     ├─ Sensory-event
     ├─ Experimental-stimulus
     ├─ Visual-presentation
     └─ Label/20_6

21.6
     ├─ Sensory-event
     ├─ Experimental-stimulus
     ├─ Visual-presentation
     └─ Label/21_6

14.8
     ├─ Sensory-event
     ├─ Experimental-stimulus
     ├─ Visual-presentation
     └─ Label/14_8

15.8
     ├─ Sensory-event
     ├─ Experimental-stimulus
     ├─ Visual-presentation
     └─ Label/15_8

16.8
     ├─ Sensory-event
     ├─ Experimental-stimulus
     ├─ Visual-presentation
     └─ Label/16_8

17.8
     ├─ Sensory-event
     ├─ Experimental-stimulus
     ├─ Visual-presentation
     └─ Label/17_8

18.8
     ├─ Sensory-event
     ├─ Experimental-stimulus
     ├─ Visual-presentation
     └─ Label/18_8

19.8
     ├─ Sensory-event
     ├─ Experimental-stimulus
     ├─ Visual-presentation
     └─ Label/19_8

20.8
     ├─ Sensory-event
     ├─ Experimental-stimulus
     ├─ Visual-presentation
     └─ Label/20_8

21.8
├─ Sensory-event
├─ Experimental-stimulus
├─ Visual-presentation
└─ Label/21_8

Paradigm-Specific Parameters

  • Detected paradigm: ssvep

  • Stimulus frequencies: [14.0, 14.2, 14.4, 14.6, 14.8, 15.0, 15.2, 15.4, 15.6, 15.8, 16.0, 16.2, 16.4, 16.6, 16.8, 17.0, 17.2, 17.4, 17.6, 17.8, 18.0, 18.2, 18.4, 18.6, 18.8, 19.0, 19.2, 19.4, 19.6, 19.8, 20.0, 20.2, 20.4, 20.6, 20.8, 21.0, 21.2, 21.4, 21.6, 21.8] Hz

  • Frequency resolution: 0.2 Hz

Data Structure

  • Trials: 240

  • Blocks per session: 6

Preprocessing

  • Data state: epoched

Signal Processing

  • Classifiers: CCA, FBCCA, ITCCA, TRCA, EEGNet

  • Feature extraction: CCA, FBCCA, TRCA

  • Frequency bands: stimulus_range=[14.0, 22.0] Hz; analysis=[13.0, 89.0] Hz

  • Spatial filters: CCA, TRCA

Cross-Validation

  • Method: leave-one-subject-out

  • Folds: 6

  • Evaluation type: within_subject, cross_subject

BCI Application

  • Applications: speller

  • Environment: lab

Tags

  • Pathology: healthy

  • Modality: visual

  • Type: perception

Documentation

  • DOI: 10.1038/s41597-025-06032-2

  • License: CC BY 4.0

  • Investigators: Heegyu Kim, Kyungho Won, Minkyu Ahn, Sung Chan Jun

  • Senior author: Sung Chan Jun

  • Institution: Gwangju Institute of Science and Technology

  • Department: School of Electrical Engineering and Computer Science, GIST

  • Country: KR

  • Repository: Figshare

  • Data URL: https://doi.org/10.6084/m9.figshare.28806815.v2

  • Publication year: 2025

  • Ethics approval: GIST IRB, No. 20211201-HR-64-02-04

  • Keywords: SSVEP, BCI, beta range, visual fatigue, 40-class speller, JFPM, EEG

References

H. Kim, K. Won, M. Ahn, and S. C. Jun, “A 40-class SSVEP speller dataset: beta range stimulation for low-fatigue BCI applications,” Scientific Data, vol. 12, p. 1751, 2025. DOI: 10.1038/s41597-025-06032-2 Appelhoff, S., Sanderson, M., Brooks, T., Vliet, M., Quentin, R., Holdgraf, C., Chaumon, M., Mikulan, E., Tavabi, K., Hochenberger, R., Welke, D., Brunner, C., Rockhill, A., Larson, E., Gramfort, A. and Jas, M. (2019). MNE-BIDS: Organizing electrophysiological data into the BIDS format and facilitating their analysis. Journal of Open Source Software 4: (1896). https://doi.org/10.21105/joss.01896 Pernet, C. R., Appelhoff, S., Gorgolewski, K. J., Flandin, G., Phillips, C., Delorme, A., Oostenveld, R. (2019). EEG-BIDS, an extension to the brain imaging data structure for electroencephalography. Scientific Data, 6, 103. https://doi.org/10.1038/s41597-019-0104-8 Generated by MOABB 1.4.3 (Mother of All BCI Benchmarks) https://github.com/NeuroTechX/moabb

Dataset Information#

Dataset ID

NM000127

Title

Kim2025 – 40-class beta-range SSVEP speller dataset

Author (year)

Kim2025_SSVEP

Canonical

Kim2025

Importable as

NM000127, Kim2025_SSVEP, Kim2025

Year

2019

Authors

Heegyu Kim, Kyungho Won, Minkyu Ahn, Sung Chan Jun

License

CC BY 4.0

Citation / DOI

Unknown

Source links

OpenNeuro | NeMAR | Source URL

Found an issue with this dataset?

If you encounter any problems with this dataset (missing files, incorrect metadata, loading errors, etc.), please let us know!

Report an Issue on GitHub

Technical Details#

Subjects & recordings
  • Subjects: 40

  • Recordings: 240

  • Tasks: 1

Channels & sampling rate
  • Channels: 31

  • Sampling rate (Hz): 1024.0

  • Duration (hours): 18.927018229166663

Tags
  • Pathology: Healthy

  • Modality: Visual

  • Type: Perception

Files & format
  • Size on disk: 8.1 GB

  • File count: 240

  • Format: BIDS

License & citation
  • License: CC BY 4.0

  • DOI: —

Provenance

API Reference#

Use the NM000127 class to access this dataset programmatically.

class eegdash.dataset.NM000127(cache_dir: str, query: dict | None = None, s3_bucket: str | None = None, **kwargs)[source]#

Bases: EEGDashDataset

Kim2025 – 40-class beta-range SSVEP speller dataset

Study:

nm000127 (NeMAR)

Author (year):

Kim2025_SSVEP

Canonical:

Kim2025

Also importable as: NM000127, Kim2025_SSVEP, Kim2025.

Modality: eeg; Experiment type: Perception; Subject type: Healthy. Subjects: 40; recordings: 240; tasks: 1.

Parameters:
  • cache_dir (str | Path) – Directory where data are cached locally.

  • query (dict | None) – Additional MongoDB-style filters to AND with the dataset selection. Must not contain the key dataset.

  • s3_bucket (str | None) – Base S3 bucket used to locate the data.

  • **kwargs (dict) – Additional keyword arguments forwarded to EEGDashDataset.

data_dir#

Local dataset cache directory (cache_dir / dataset_id).

Type:

Path

query#

Merged query with the dataset filter applied.

Type:

dict

records#

Metadata records used to build the dataset, if pre-fetched.

Type:

list[dict] | None

Notes

Each item is a recording; recording-level metadata are available via dataset.description. query supports MongoDB-style filters on fields in ALLOWED_QUERY_FIELDS and is combined with the dataset filter. Dataset-specific caveats are not provided in the summary metadata.

References

OpenNeuro dataset: https://openneuro.org/datasets/nm000127 NeMAR dataset: https://nemar.org/dataexplorer/detail?dataset_id=nm000127

Examples

>>> from eegdash.dataset import NM000127
>>> dataset = NM000127(cache_dir="./data")
>>> recording = dataset[0]
>>> raw = recording.load()
__init__(cache_dir: str, query: dict | None = None, s3_bucket: str | None = None, **kwargs)[source]#
save(path, overwrite=False)[source]#

Save the dataset to disk.

Parameters:
  • path (str or Path) – Destination file path.

  • overwrite (bool, default False) – If True, overwrite existing file.

Return type:

None

See Also#