Table 1.
Electrode sampling: anatomical region in which each electrode contact was located, following FreeSurfer automated parcellation
| Brain Area | No. of Electrodes | No. of Subjects |
|---|---|---|
| Amygdala | 33 | 4 |
| Hippocampus | 30 | 5 |
| Entorhinal | 4 | 2 |
| Parahippocampal | 9 | 3 |
| Insula | 55 | 5 |
| Lateral orbitofrontal | 55 | 4 |
| Medial orbitofrontal | 25 | 4 |
| Pars orbitalis | 9 | 3 |
| Olfactory bulb* | 10 | 3 |
| Piriform* | 9 | 3 |
| Pars triangularis | 24 | 5 |
| Pars opercularis | 25 | 6 |
| Frontal-rostral middle | 27 | 5 |
| Frontal-caudal middle | 27 | 4 |
| Frontal-superior | 22 | 4 |
| Precentral | 41 | 6 |
| Paracentral | 10 | 3 |
| Postcentral | 33 | 6 |
| Cingulate-anterior | 14 | 5 |
| Cingulate-middle | 10 | 5 |
| Parietal-inferior | 7 | 3 |
| Parietal-superior | 7 | 3 |
| Precuneus | 9 | 4 |
| Cuneus-calcarine-occipital | 12 | 2 |
| Lingual | 12 | 3 |
| Fusiform | 15 | 5 |
| Temporal-middle | 114 | 5 |
| Temporal-inferior | 43 | 4 |
| Temporal-superior | 93 | 6 |
| Supramarginal | 17 | 4 |
| Transverse temporal | 26 | 4 |
| White matter | 319 | 5 |
| CSF | 10 | 5 |
| Total | 1,137 | 6 |
Shown are the locations of all electrodes (n = 1,137 electrodes in 6 patients) included in the analysis of natural breathing (Figs. 2–8) after FreeSurfer parcellation (Fischl et al. 2004), the number of electrodes in each area, and the number of subjects contributing to each area. Electrodes showing any sign of abnormal epileptiform discharges were excluded from the analysis. Asterisks indicate electrode locations after FreeSurfer parcellation correction; these electrodes were automatically assigned to orbitofrontal cortex and/or the pars orbitalis region by FreeSurfer parcellation in the ventral aspect of the frontal lobe. Assignment to piriform cortex or olfactory bulb was based on visual inspection of the postimplantation MRI and CT scans (see materials and methods).