Intracerebral Epileptic Discharges Without and During Concurrent tDCS in an Epileptic Patient

Published: 27 January 2023| Version 1 | DOI: 10.17632/3krd4hrk86.1


Intracerebral EEG recordings of a patient (female, 19 yo) suffering from refractory insulo-opercular epilepsy. She gave informed consent to participate in this study (NCT03644732). Intracerebral electrode positions (see also Figure): A’, B’, C’ and P’, targeted the temporal pole, the mesial and neocortical temporal lobe. H’, I’, L’, O’, R’, S’ and T’ targeted the insular cortex and the operculum. G’, J’, K’, M’, W’ and X’ targeted the mesial and neocortical frontal lobe. IEEG signals were recorded at a 1024 Hz sampling rate with a 256-channel amplifier (SD LTM 256 Headbox, Micromed, Italy). The reference electrode was an iEEG contact located in the white matter. The tDCS parameters were +1mA over the anode (T7 electrode) and -1mA over the cathode (C6 electrode) and a 20-minute total duration was set. Two HD electrodes (12mm external diameter; Soterix Medical®, New York, NY, USA) were used (with Z < 5 kOhms). During the four days of iEEG investigation, five spontaneous epileptic seizures occurred, and ictal epileptic discharges were recorded in S’1-2 to 8-9 and O’5-6 to O’9-10 contacts. Seizure#5 occured after 8min of tDCS. Five datasets of ictal epileptic discharges outside (IED1-4) and during tDCS (IED*) were identified and selected during tDCS with the same 60 seconds duration (bipolar montage).


Steps to reproduce

Patient inclusion Depth multi-contact electrodes implantation and localization (MR-CT co-registration) Aseptic small-HD tDCS electrode placement Intracerebral EEG recordings with concurrent tDCS tDCS parameters : +1mA over the anode (T7 scalp electrode) and -1mA over the cathode (C6 scalp electrode)


Centre Hospitalier Universitaire de Nancy, CNRS Delegation Centre-Est, Universite de Lorraine


Neuromodulation, Epilepsy, Electroencephalography in Epilepsy, Depth Recording Electroencephalography, Brain Stimulation, Transcranial Direct Current Stimulation, Clinical Neuroscience


Université de Lorraine


City College of New York


Conseil régional du Grand Est

PhD grant