Physiology Data Definitions

M-BIDS extends the BIDS Physiological recordings specification with stricter Calibench naming and metadata rules. Each physiological modality SHOULD be stored in a separate modality-specific file with a matching JSON sidecar.

As in BIDS, compressed *_physio.tsv.gz files MUST NOT include a header row. The column names MUST be provided by the Columns list in the matching *_physio.json sidecar.

All Calibench physiology time-series files use timestamp as the first column. The timestamp column is a continuously increasing time value in seconds, relative to the start of the trimmed recording.

General file pattern

sub-<participant_label>/
└── physio/
    ├── sub-<participant_label>_task-acquisition_recording-scr_physio.json
    ├── sub-<participant_label>_task-acquisition_recording-scr_physio.tsv.gz
    ├── sub-<participant_label>_task-acquisition_recording-ecg_physio.json
    ├── sub-<participant_label>_task-acquisition_recording-ecg_physio.tsv.gz
    ├── sub-<participant_label>_task-acquisition_recording-resp_physio.json
    └── sub-<participant_label>_task-acquisition_recording-resp_physio.tsv.gz

The same pattern is used for task-extinction. Eye-tracking recordings are also stored in physio/ when they are aligned with physiological recordings.

Common sidecar fields

BIDS defines common physiology sidecar fields such as Columns, StartTime, and SamplingFrequency. In addition to these BIDS fields, every Calibench *_physio.json sidecar MUST contain the following fields when applicable:

Table 1: Common physiology sidecar fields
Key	Description	Example
`Columns`	Column names for the matching headerless TSV file. The first entry must be `timestamp`.	`timestamp, scr`
`StartTime`	Time of the first sample relative to the recording start.	`0.0`
`SamplingFrequency`	Sampling frequency in Hz.	`2000`
`PhysioType`	Recording type used by the importer.	`generic`
`TrimPoints`	Source-data time points used to trim the exported recording.	`[882.7075, 1530.7065]`
`Duration`	Duration of the exported recording in seconds.	`647.999`
`timestamp`	Metadata object describing the timestamp column.	`Units: s`

Modality-specific definitions

Guidelines for individual modalities are given below.

Physio Data Modalities: