Neuromodulation, Refractory Epilepsy
Conditions
Keywords
SEEG, Piriform cortex, Electrical stimulation, Electrophysiology
Brief summary
The prospective study aims to characterize the network-specific modulatory effects of piriform cortex stimulation in patients undergoing stereotactic EEG for drug-resistant epilepsy. Using multimodal data, it seeks to link stimulation-evoked electrophysiological responses across brain networks with clinical outcomes, to inform targeted neuromodulation therapies.
Detailed description
This study employs stereotactic electroencephalography (SEEG) to investigate the network-specific mechanisms of brain modulation induced by electrical stimulation of the piriform cortex. By analyzing high-density intracranial recordings, combined with structural and functional neuroimaging, the research systematically characterizes how focal stimulation differentially engages and reorganizes activity across large-scale neural circuits. The primary focus is to decode the electrophysiological signatures of network engagement-including changes in spectral power, phase synchronization, and information flow-to reveal fundamental principles of targeted neuromodulation in the human brain.
Interventions
DEVICESEEG recordings and SPES
The intervention involves single-pulse electrical stimulation (SPES) applied during stereotactic electroencephalography (SEEG) monitoring. Low-intensity, standardized electrical pulses are delivered to targeted contacts within or near the piriform cortex via implanted depth electrodes, while simultaneous full-bandwidth SEEG recordings capture network-wide electrophysiological responses, allowing characterization of stimulation-evoked brain network activation and modulation patterns.
Sponsors
Xuanwu Hospital, Beijing
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
BASIC_SCIENCE
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
14 Years to 65 Years
Healthy volunteers
No
Inclusion criteria
* The patients were diagnosed with drug-resistant epilepsy. * The patients underwent stereoelectroencephalography (SEEG) implantation for pre-surgical evaluation of epilepsy, with at least one electrode target reaching the piriform cortex * Participants/parents/legal guardian provide informed consent for inclusion
Exclusion criteria
* Subjects that experience surgical complications during the implant procedure will be excluded from the study
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Seizure Discharge Suppression Rate | 72 hours | Quantified as the percentage reduction in the frequency of spikes and interictal epileptiform discharges (IEDs) during active stimulation compared to the baseline period. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| N1 Component Amplitude and Latency: | 72 hours | Amplitude (μV) and latency (ms) of the primary cortical evoked response (N1 wave). |
| Spatial Distribution of Activation | 72 hours | The extent of cortical activation, assessed by the number of electrode contacts showing significant evoked responses. |
| Effective Connectivity Change： | 72 hours | Alterations in effective connectivity strength (e.g., measured by Granger causality within a 500 ms time window). |
| Single-Pulse Stimulation Amplitude: | 72 hours | The minimum current intensity (mA) required to elicit a reproducible response. |
| Functional Network Reconfiguration | 72 hours | Changes in node centrality metrics (e.g., betweenness centrality, degree centrality) based on graph-theoretical analysis of functional networks. |
| Incidence of Treatment-Emergent Adverse Events [Safety and Tolerability] | 72 hours | Adverse Events: Incidence and severity of adverse events specifically associated with piriform cortex stimulation. |
| Phase-Amplitude Coupling Index | 72 hours | Changes in coupling between the phase of low-frequency oscillations and the amplitude of the gamma band (30-80 Hz). |
Countries
China
Contacts
Primary ContactLiankun Ren, MD
Outcome results
None listed