How to add channel locations for ESG data in BIDS?

Hi NeuroStars,

I would like to share data sets from three different experiments that include simultaneous electroencephalography (EEG) and electrospinography (ESG) recordings. At the moment ESG channels are classified as MISC channels. However, I would still like to add the locations of ESG. I have between 40 and 80 ESG channels and since there is no standard for naming their position remains unclear. I do not know how to best add the locations of the electrode over the spinal cord in the BIDS format. Any recommendations?

Best wishes

Birgit Nierula

1 Like

Hi @Birgit, you could add a custom column to the electrodes.tsv file in which you enter “codes” corresponding to positions. Then you would explain these codes in an accompanying electrodes.json file.

For example this could be a TSV file, with ABC1 being an electrode:

name	x	y	z	spin_loc	type
ABC1	n/a	n/a	n/a	code2	spinal
...

And this could be a part of the JSON file:

{
	"spin_loc": {
		"Description": "General description of how locations"
		"Levels": {
			"code2": "description of the location meant by 'code2'"
		}
	}
}

For the real data you’d have many more rows (and potentially columns) in the TSV file, and more entries in the JSON file → especially more “Levels” for the “spin_loc” entry in the JSON file.

Thank you @sappelhoff, this is very helpful!