EEG-fMRI results and Time-Frequency (TF) statistical maps of SEEG recordings from patient 5.

<p>A – Scalp EEG showing electrographic seizure over perisylvian region and associated BOLD changes. Functional map is co-registered with anatomical MRI and CT showing the sampling of P-C, insula and temporal cortex by SEEG electrodes (marked by white arrows, other electrodes are not shown). Functional maps show activations in left insula and bilateral cingulate and deactivations in DMN nodes of left hemisphere. B - SEEG traces showing typical electrographic seizure originating from left insula (lower 2 traces) and SEEG in left PCC, P-C, IPL, DLPFC, inferior occipital and superior temporal regions. Each region was sampled with 2 consecutive bipolar channels 5 mm apart, and higher number denotes a more lateral channel. Note the spread of seizure activity to the IPL and temporal cortex and that the activity in IPL is identical to the activity measured on the scalp. C – Schematic representation of a typical electrographic seizure (not in scale) and 1 s epochs centered at the start, center, and end of the seizure. Epochs can overlap depending on the length of the IED. D – TF maps of statistically significant z values comparing start, center, and end of IED with baseline. They show decrease in gamma and increase in frequencies<30 Hz coinciding with the center of the seizure in PCC, P-C, DLPFC, whereas IPL and superior temporal gyrus show increase of frequencies up to 60 and 120 Hz, respectively, secondary to spread of epileptic activity. Boxed TF maps are shown in higher magnification on the right. Statistical threshold obtained after false discovery rate correction (indicated as “1” in color bar). Plots are saturated at a z value that is double the threshold value (indicated as “2”). Non-significant pixels (below false discovery rate threshold) are displayed in green.