Characterising the Network-Specific Effects of Piriform Cortex Stimulation Via SEEG

Capital Medical University

Status: Not yet enrolling

Conditions: Refractory Epilepsy; Neuromodulation

Treatments: Device: SEEG recordings and SPES

Study type: Interventional

Funder types: Other

Identifiers

NCT07305311

2025-292-202

Details and patient eligibility

About

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.

Full 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.

Enrollment: 10 estimated patients

Sex: All

Ages: 14 to 65 years old

Volunteers: No Healthy Volunteers

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

Trial design

Primary purpose: Basic Science

Allocation: N/A

Interventional model: Single Group Assignment

Masking: None (Open label)

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10 participants in 1 patient group

SEEG recordings and SPES effects

Experimental group

Description:

This arm encompasses patients with drug-resistant focal epilepsy who underwent intracranial monitoring via stereotactically implanted depth electrodes (SEEG) as part of their standard presurgical evaluation. During the monitoring period, these patients additionally underwent systematic Single-Pulse Electrical Stimulation (SPES) mapping. SPES was administered according to a standardized clinical protocol, involving the delivery of single, low-intensity electrical pulses to selected electrode contacts-including those located within or adjacent to the piriform cortex-while recording the evoked electrophysiological responses across the implanted SEEG network. The data collected in this arm include continuous intracranial EEG recordings, precise stimulation parameters (location, intensity), and the corresponding electrophysiological responses used to characterize cortico-cortical evoked potentials and network connectivity.

Treatment:

Device: SEEG recordings and SPES