Multi-level Approach of Brain Activity Using Intracranial Electrodes in Epileptic Patients

Institut National de la Santé Et de la Recherche Médicale, France50 enrolled

Overview

The main goal of this project is to study the mechanisms of epileptic activities using intracranial macro and micro electrodes in epileptic patients undergoing pre-surgical investigation. The recordings will also be used to study physiological mechanisms like sleep and different cognitive functions.

Study Type

INTERVENTIONAL

Allocation

Purpose

BASIC_SCIENCE

Masking

NONE

Enrollment

Conditions

Focal Epilepsy Electrodes, Implanted Cognitive Function Neurophysiology

Interventions

Eligibility

Sex: ALLMin age: 18 Years

Medical Language ↔ Plain English

Inclusion Criteria: * Patients with focal drug-resistant epilepsy * Patients who undergo a presurgical evaluation with intracranial electrodes in the videoEEG unit of the Neurology department at the Pitié-Salpêtrière hospital. * Patients who have been informed and provided written informed consent to take part in the study Exclusion Criteria: * Contraindication for an intracranial investigation (with macro-electrodes) : intercurrent infectious syndrome, decompensated associated pathology (cardiac, pulmonary, renal, hepatic), patient with increased risk of infection (ex: under immunosuppressive therapy) * Pregnant or parturient woman * Breastfeeding woman * Minor person or legally protected adult (tutelage, legal guardianship, maintenance of justice)

Outcomes

Primary Outcomes

Identification of single unit changes at seizure emergence

In order to identify biomarkers of epileptic seizures we will study single neuron activities (firing rate) using spike sorting at different time periods (before, during and after seizures and during interictal periods) We expect to observe significant changes in firing rate across the different time periods.

Time frame: Whole duration of the clinical inverstigation, until 4 weeks

Identification of local field potential (LFP) changes at seizure emergence

In order to identify biomarkers of epileptic seizures we will study LFP power using time frequency analysis at different time periods (before, during and after seizures and during interictal periods) We expect to observe significant changes in LFP power across the different time periods.

Time frame: Whole duration of the clinical inverstigation, until 4 weeks

Secondary Outcomes

Comparison of single unit activity before seizure according to brain localization

We will compare firing rate before seizure according to brain regions (anatomy and involvement in the seizure onset zone)

Time frame: Whole duration ofthe clinical inverstigation, until 4 weeks

Identification of single unit changes during physiological brain activity

We will compare firing rates during resting states and stimulus induced states. We expect to observe significant changes in firing rate between states.

Time frame: Whole duration ofthe clinical inverstigation, until 4 weeks

Identification of LFP power changes during physiological brain activity

We will compare LFP power during resting states and stimulus induced states. We expect to observe significant changes in LFP power between states.

Time frame: Whole duration ofthe clinical inverstigation, until 4 weeks

Multilevel study of brain activity

We will look for correlation between firing rates and LFP power changes.

Time frame: Whole duration ofthe clinical inverstigation, until 4 weeks

Multi-level Approach of Brain Activity Using Intracranial Electrodes in Epileptic Patients

Overview

Conditions

Interventions

Eligibility

Locations (1)

Outcomes

Primary Outcomes

Secondary Outcomes

Central Contacts