moabb.datasets.Wang2026Handwriting#

class moabb.datasets.Wang2026Handwriting(subjects=None, sessions=None, *, return_all_modalities=False)[source]#

Bases: BaseBIDSDataset

[source]

Dataset Snapshot

Wang2026Handwriting

Cognitive, 11 classes

AuthorsFan Wang, Yanxiao Chen, Peng Wang, Anmin Gong, Hui Xu, Yunfa Fu

🇨🇳 Minjiang University, CN·2026
Cognitive Code: Wang2026Handwriting 21 subjects 2 sessions 32 ch 1000 Hz 11 classes 4.0 s trials CC BY 4.0

Class Labels: horizontal, vertical, left_falling, right_falling, turning, a, o, e, ...

Overview

Chinese handwriting imagery dataset (CCS-HI / SV-HI) from Wang et al. 2026 (cognitive paradigm).

Dataset from

The dataset contains EEG recordings from 21 healthy, right-handed adults (10 female, 11 male, aged 22-32 years) performing two handwriting-imagery tasks:

  • - CCS-HI (Chinese character strokes imagery): five stroke classes (horizontal, vertical, left-falling, right-falling, turning), 40 trials per class;
  • SV-HI (single vowels imagery): six Pinyin vowel classes (a, o, e, i, u, ü), 40 trials per class.

Each subject completed both tasks in each of two sessions recorded on separate days. Every trial is a 4 s window of kinesthetic handwriting imagery cued by a visual stimulus, followed by a rest period. EEG was recorded from 32 Ag/AgCl electrodes (10-10 layout) at 1000 Hz, referenced to CPz with Fpz as ground, with a 0.1-100 Hz hardware band-pass and no software filtering applied before disclosure.

The subjects split into expert and novice groups by their handwriting imagery performance (see the group column of the release's participants.tsv), which makes the dataset usable for both within-session and expert/novice transfer analyses.

This loader reads the authors' BIDS release hosted on figshare. Each subject is distributed as a single zip containing both tasks for both sessions; the loader downloads it, unpacks it beside the other BIDS sidecars it fetches from the same deposit, and reads the resulting BIDS tree with :class:`mne_bids`. Sessions are numbered "0" and "1" in MOABB and runs are named after the BIDS task (CCSHI / SVHI).

Citation & Impact

Stimulus Protocol
../_images/Wang2026Handwriting.svg

4s task window per trial · 11-class cognitive paradigm · 2 runs/session across 2 sessions

HED Event Tags
HED tags11/11 events annotated

Source: MOABB BIDS HED annotation mapping.

Label
11
Sensory-event
11
horizontal
Sensory-eventLabel
vertical
Sensory-eventLabel
left_falling
Sensory-eventLabel
right_falling
Sensory-eventLabel
turning
Sensory-eventLabel
a
Sensory-eventLabel
o
Sensory-eventLabel
e
Sensory-eventLabel
i
Sensory-eventLabel
u
Sensory-eventLabel
v
Sensory-eventLabel

HED tree view

Tree · horizontal
├─ Sensory-event
└─ Label
Tree · vertical
├─ Sensory-event
└─ Label
Tree · left_falling
├─ Sensory-event
└─ Label
Tree · right_falling
├─ Sensory-event
└─ Label
Tree · turning
├─ Sensory-event
└─ Label
Tree · a
├─ Sensory-event
└─ Label
Tree · o
├─ Sensory-event
└─ Label
Tree · e
├─ Sensory-event
└─ Label
Tree · i
├─ Sensory-event
└─ Label
Tree · u
├─ Sensory-event
└─ Label
Tree · v
├─ Sensory-event
└─ Label
Channel Summary
Total channels32
EEG32 (Ag/AgCl)
Montage10-05
Sampling1000 Hz
ReferenceCPz
Notch / line50 Hz

This diagram is automatically generated from MOABB metadata. Please consult the original publication to confirm the experimental protocol details.

Chinese handwriting imagery dataset (CCS-HI / SV-HI) from Wang et al. 2026 (cognitive paradigm).

Dataset from [1].

The dataset contains EEG recordings from 21 healthy, right-handed adults (10 female, 11 male, aged 22-32 years) performing two handwriting-imagery tasks:

  • CCS-HI (Chinese character strokes imagery): five stroke classes (horizontal, vertical, left-falling, right-falling, turning), 40 trials per class;

  • SV-HI (single vowels imagery): six Pinyin vowel classes (a, o, e, i, u, ü), 40 trials per class.

Each subject completed both tasks in each of two sessions recorded on separate days. Every trial is a 4 s window of kinesthetic handwriting imagery cued by a visual stimulus, followed by a rest period. EEG was recorded from 32 Ag/AgCl electrodes (10-10 layout) at 1000 Hz, referenced to CPz with Fpz as ground, with a 0.1-100 Hz hardware band-pass and no software filtering applied before disclosure.

The subjects split into expert and novice groups by their handwriting imagery performance (see the group column of the release’s participants.tsv), which makes the dataset usable for both within-session and expert/novice transfer analyses.

Important

The release flags two sessions with fewer valid trials than the protocol’s standard count (sub-06 session 2 of SV-HI: 225 instead of 240; sub-13 session 2 of CCS-HI: 162 instead of 200). The authors attribute this to trigger misfires during acquisition. MOABB keeps those sessions as released; the counts above describe the standard session, and the per-subject trial totals reported by get_data() reflect what each session actually contains.

This loader reads the authors’ BIDS release hosted on figshare. Each subject is distributed as a single zip containing both tasks for both sessions; the loader downloads it, unpacks it beside the other BIDS sidecars it fetches from the same deposit, and reads the resulting BIDS tree with mne_bids. Sessions are numbered "0" and "1" in MOABB and runs are named after the BIDS task (CCSHI / SVHI).

References

[1]

F. Wang, Y. Chen, P. Wang, A. Gong, H. Xu, and Y. Fu, “An EEG dataset for handwriting imagery decoding of Chinese character strokes and Pinyin single vowels,” Scientific Data, 2026. DOI: 10.1038/s41597-026-06708-3

from moabb.datasets import Wang2026Handwriting
dataset = Wang2026Handwriting()
data = dataset.get_data(subjects=[1])
print(data[1])

Dataset summary

#Subj

21

#Chan

32

#Classes

5

#Trials / class

40

Trials length

4 s

Freq

1000 Hz

#Sessions

2

#Runs

2

Total_trials

18480

Participants

  • Population: healthy

  • Age: 25.7619 (range: 22-32) years

  • Handedness: {‘right’: 21}

  • BCI experience: mixed (expert and novice groups)

Equipment

  • Amplifier: Neuracle NeuSenW32 32-channel Ag/AgCl cap

  • Electrodes: Ag/AgCl

  • Montage: standard_1005

  • Reference: CPz

Preprocessing

  • Data state: raw

  • Bandpass filter: 0.1-100 Hz

  • Notes: Recorded with a 0.1-100 Hz hardware band-pass; the release applies no software filter.

Data Access

Experimental Protocol

  • Paradigm: cognitive

  • Task type: handwriting_imagery

  • Feedback: none

  • Stimulus: visual cue (stroke or vowel to imagine writing)

Notes

Added in version 1.8.0.

__init__(subjects=None, sessions=None, *, return_all_modalities=False)[source]#

Initialize function for the BaseDataset.

property all_subjects#

Full list of subjects available in this dataset (unfiltered).

convert_to_bids(path=None, subjects=None, overwrite=False, format='EDF', verbose=None, generate_figures=False)[source]#

Convert the dataset to BIDS format.

Saves the raw EEG data in a BIDS-compliant directory structure. Unlike the caching mechanism (see CacheConfig), the files produced here do not contain a processing-pipeline hash (desc-<hash>) in their names, making the output a clean, shareable BIDS dataset.

Parameters:
  • path (str | Path | None) – Directory under which the BIDS dataset will be written. If None the default MNE data directory is used (same default as the rest of MOABB).

  • subjects (list of int | None) – Subject numbers to convert. If None, all subjects in subject_list are converted.

  • overwrite (bool) – If True, existing BIDS files for a subject are removed before saving. Default is False.

  • format (str) – The file format for the raw EEG data. Supported values are "EDF" (default), "BrainVision", and "EEGLAB".

  • verbose (str | None) – Verbosity level forwarded to MNE/MNE-BIDS.

  • generate_figures (bool) – If True, generate interactive neural signature HTML figures in {bids_root}/derivatives/neural_signatures/. Requires plotly (pip install moabb[interactive]). Default is False.

Returns:

bids_root – Path to the root of the written BIDS dataset.

Return type:

pathlib.Path

Examples

>>> from moabb.datasets import AlexMI
>>> dataset = AlexMI()
>>> bids_root = dataset.convert_to_bids(path="/tmp/bids", subjects=[1])

Notes

Use CacheConfig to configure caching for get_data(). Use moabb.datasets.bids_interface.get_bids_root to get the BIDS root path.

Added in version 1.5.

data_path(subject, path=None, force_update=False, update_path=None, verbose=None)[source]#

Get path to local copy of a subject data.

Parameters:
  • subject (int) – Number of subject to use

  • path (None | str) – Location of where to look for the data storing location. If None, the environment variable or config parameter MNE_DATASETS_(dataset)_PATH is used. If it doesn’t exist, the “~/mne_data” directory is used. If the dataset is not found under the given path, the data will be automatically downloaded to the specified folder.

  • force_update (bool) – Force update of the dataset even if a local copy exists.

  • update_path (bool | None Deprecated) – If True, set the MNE_DATASETS_(dataset)_PATH in mne-python config to the given path. If None, the user is prompted.

  • verbose (bool, str, int, or None) – If not None, override default verbose level (see mne.verbose()).

Returns:

path – Local path to the given data file. This path is contained inside a list of length one, for compatibility.

Return type:

list of str

download(subject_list=None, path=None, force_update=False, update_path=None, accept=False, verbose=None)[source]#

Download the BIDS trees of the requested subjects.

get_additional_metadata(subject, session, run)[source]#

Load additional metadata for a specific subject, session, and run.

Parameters:
  • subject (str) – The identifier for the subject.

  • session (str) – The identifier for the session.

  • run (str) – The identifier for the run.

Returns:

A DataFrame containing the additional metadata if available, otherwise None.

Return type:

None | pandas.DataFrame

get_block_repetition(paradigm, subjects, block_list, repetition_list)[source]#

Select data for all provided subjects, blocks and repetitions.

subject -> session -> run -> block -> repetition

See also

get_data

Parameters:
  • subjects (List of int) – List of subject number

  • block_list (List of int) – List of block number

  • repetition_list (List of int) – List of repetition number inside a block

Returns:

data – dict containing the raw data

Return type:

Dict

get_data(subjects=None, cache_config=None, process_pipeline=None, n_jobs=1)[source]#

Return the data corresponding to a list of subjects.

The returned data is a dictionary with the following structure:

data = {"subject_id": {"session_id": {"run_id": run}}}

subjects are on top, then we have sessions, then runs. A sessions is a recording done in a single day, without removing the EEG cap. A session is constitued of at least one run. A run is a single contiguous recording. Some dataset break session in multiple runs.

Processing steps can optionally be applied to the data using the *_pipeline arguments. These pipelines are applied in the following order: raw_pipeline -> epochs_pipeline -> array_pipeline. If a *_pipeline argument is None, the step will be skipped. Therefore, the array_pipeline may either receive a mne.io.Raw or a mne.Epochs object as input depending on whether epochs_pipeline is None or not.

Parameters:
  • subjects (List of int) – List of subject number

  • cache_config (dict | CacheConfig) – Configuration for caching of datasets. See CacheConfig for details.

  • process_pipeline (sklearn.pipeline.Pipeline | None) – Optional processing pipeline to apply to the data. To generate an adequate pipeline, we recommend using moabb.make_process_pipelines(). This pipeline will receive mne.io.BaseRaw objects. The steps names of this pipeline should be elements of StepType. According to their name, the steps should either return a mne.io.BaseRaw, a mne.Epochs, or a numpy.ndarray. This pipeline must be “fixed” because it will not be trained, i.e. no call to fit will be made.

  • n_jobs (int) – Number of jobs to run in parallel over subjects (passed to joblib.Parallel). Default 1 (sequential). Per-subject processing (reading, filtering, resampling, epoching) is independent, so this gives a near-linear speedup for datasets with many subjects.

Returns:

data – dict containing the raw data

Return type:

Dict

property metadata[source]#

Return structured metadata for this dataset.

Returns the DatasetMetadata object from the centralized catalog, or None if metadata is not available for this dataset.

Returns:

The metadata object containing acquisition parameters, participant demographics, experiment details, and documentation. Returns None if no metadata is registered for this dataset.

Return type:

DatasetMetadata | None

Examples

>>> from moabb.datasets import BNCI2014_001
>>> dataset = BNCI2014_001()
>>> dataset.metadata.participants.n_subjects
9
>>> dataset.metadata.acquisition.sampling_rate
250.0
sourcedata_path(subject=None, path=None, force_update=False, verbose=None)[source]#

Get the dataset’s original pre-BIDS distribution from NEMAR.

Where data_path() fetches the original files from the upstream host, this fetches the copy NEMAR mirrors under sourcedata/. The files keep their upstream names, so the two are interchangeable in content – but NEMAR stays reachable when the upstream host is slow, rate-limited, behind a bot gate, or retired.

Parameters:
  • subject (int | str | None) – Restrict the download to one subject, resolved through the deposit’s sourcedata_provenance.json. Deposits enriched before that manifest recorded subjects fall back to the whole tree with a warning. When None the whole tree is fetched.

  • path (None | str) – Base path where MOABB stores datasets.

  • force_update (bool) – Re-fetch even when a local copy is present.

  • verbose (bool, str, int, or None) – If not None, override default verbose level.

Returns:

Local path to the sourcedata directory.

Return type:

str

Raises:
  • ValueError – If the dataset declares no nemar_id.

  • moabb.datasets.download.NemarDownloadError – If the download fails or the deposit publishes no sourcedata/.