README.md

metadata

license: cc0-1.0
tags:
  - eeg
  - sleep-staging
  - in-ear-eeg
  - scalp-eeg
  - hdf5

EESM23-Processed

Processed HDF5 export of the EESM23 OpenNeuro dataset. It contains paired in-ear EEG and scalp EEG sleep-staging samples from the scored ses-001 and ses-002 recordings of 10 subjects.

Preprocessing

Generated with Ear-EEG-FM-Benchmark/dataset/preprocess_eesm23.py using schema/eegfm version 0.5.0:

• 0.1–100 Hz band-pass and 50 Hz notch filtering on each continuous recording
• no re-referencing, resampling, or channel renaming
• each labeled 30-second AASM scoring event is split into seven non-overlapping 4-second windows; the final 2 seconds are unused
• classes: Wake, N1, N2, N3, REM; Artefact events are dropped
• real sensor/data-loss NaN/Inf samples are preserved and recorded in overall and per-channel quality fields
• the ear-EEG and scalp outputs are strictly row-aligned; a session is excluded from both when either modality is missing/unreadable, and a window is retained only when it exists in both modalities
• recording bounds are checked separately for every 4-second window
• all signal values are stored as float32 microvolts at 250 Hz

Brief device data-loss gaps are interpolated before filtering to prevent FIR-kernel contamination, after which the original NaN positions are restored before window selection.

Files

File	Channels	Shape (N, C, T)	Size
eesm23-in-ear-eeg.h5	RB, RT, LB, LT	(108673, 4, 1000)	1.66 GiB
eesm23-scalp-eeg.h5	M1, F3, C3, O1, M2, F4, C4, O2	(108673, 8, 1000)	3.28 GiB

Label distribution:

Wake	N1	N2	N3	REM
9,631	9,044	51,302	17,458	21,238

Retained and discarded windows

The source scoring files define 119,518 potential 4-second windows, of which 115,906 carry one of the five retained sleep-stage labels and 3,612 are labeled Artefact. The final files contain 108,673 strictly paired windows per modality. The exclusions are:

Reason	Windows
Artefact label (outside the five-class task)	3,612
Entire sub-006/ses-002 pair: truncated/unreadable PSG	7,217
sub-002/ses-001: PSG window has no in-bounds ear-EEG partner	15
sub-010/ses-002: PSG window has no in-bounds ear-EEG partner	1
Total excluded, including Artefact	10,845

Among the five-class candidates, 7,233 windows are excluded by recording availability or strict pairing. No window is excluded because it contains NaN/Inf. The final files retain 3,491 in-ear windows and 13,328 scalp windows with at least one non-finite sample; their indices remain paired even when quality differs between modalities.

HDF5 schema (v0.5)

/data                 (N, C, 1000) float32
/durations            (N,)         int64
/nan_fraction         (N,)         float32
/channel_nan_fraction (N, C)       float32
/labels               (N,)         int64
/sample_id            (N,)         int64
/subject              (N,)         string
/session              (N,)         string
/task                 (N,)         string
/acquisition          (N,)         string
/run                   (N,)         string
/recording_id          (N,)         string
/trial_id              (N,)         int64
/event_id              (N,)         int64
/split_group_id        (N,)         int64
/window_start_sample   (N,)         int64
/window_stop_sample    (N,)         int64
/ch_names              (C,)         string

event_id and split_group_id identify the source 30-second scoring row. Keep all windows sharing a split group together when constructing train/validation/test partitions.

Important attributes include sfreq, class_names, unit, eegfm_version, preprocess_config_json, split_group_kind, and window_reference.