Fig. 1.

Electrode localization in 2 representative patients. Two methods of electrode survey are used. A: CT (left). Postoperative skull radiograph is from 1 subject implanted with 20 stereo-depth EEG (sEEG) electrode arrays. Of the 320 contacts implanted in this subject, 231 were analyzed for breathing-related activity because they were outside the seizure onset zone and provided artifact-free signals. Right, MRI image of the same patient, showing 2 electrode arrays with the deepest contacts (1–4) in the hippocampi (red), superficial electrodes in the superior temporal gyrus (green), and a number of intervening electrodes lying in the white matter. B: CT (left). Lateral view of head radiograph is from the 1 subject who was implanted with subdural ECoG grids and strips. Right, MRI reconstruction showing the location of the electrodes on a parcellated brain (FreeSurfer; Dale et al. 1999; Fischl et al. 1999).