A large proportion of patients (approximately 30%) with drug-resistant epilepsy are not eligible for surgical treatment. The alternatives that can be offered to reduce the frequency of seizures are neuromodulation (vagus nerve stimulation (VNS), deep brain stimulation (DBS), or transcranial direct current stimulation (tDCS)). Most of these alternatives require invasive procedures and therefore carry risks.

Neurofeedback (NFB) is a potential adjunctive treatment that allows patients to self-modulate brain activity and thus reduce seizure frequency in a non-invasive manner.

This technique involves measuring neurophysiological activity using a technical interface to extract a parameter of interest, which is presented in real time to the participant, who has been trained and has learned how to modify it.

NFB is of interest in various neurological and psychiatric diseases and can lead to improvement in mood disorders, which are frequently associated with epilepsy. Previous NFB methods in epilepsy aimed to modulate sensorimotor rhythms or slow cortical potentials. The investigators propose an innovative EEG-NFB paradigm based on real-time estimation of EEG functional connectivity (FC) measured on the scalp EEG (NFC-FC).

This paradigm was developed based on previous studies demonstrating increased functional brain connectivity during the interictal period and decreased synchrony induced by VNS and transcranial electrical stimulation as a possible anti-epileptic mechanism.

This study consists of a randomized, double-blind comparison between NFB-FC and sham-NFB (control). The effect of this functional connectivity-based NeuroFeedBack (NFB-FC) will be evaluated on the number of seizures before and after treatment, as well as on their severity and on criteria related to quality of life.

In this study, two healthy volunteers will be recruited in order to generate the sham sessions.

For patients :

Inclusion Criteria:

• Male or female patient between 18 and 65 years old
• Patient suffering from focal or multifocal drug-resistant epilepsy
• Patient having a number of seizures: at least 3 / month during the baseline
• Patient's IQ, which in the investigator's opinion will enable questionnaires and neuropsychological assessments to be carried out;
• Patient having stable medications for epilepsy 4 weeks before the baseline (except rescue treatment);
• Patient able to understand, speak and write in French;
• Patient willing to participate, and gave written consent to the study after receiving clear information
• Patient beneficiary or affiliated to a health insurance plan

Exclusion Criteria:

• - Difficulty reading or understanding the French language or inability to understand information about the study
• Generalized epilepsy
• Major visual impairment incompatible with the realization of neurofeedback, based on investigator's opinion.
• Patient currently having psychogenic non-epileptic seizures
• Any condition that makes the study subject, in the opinion of the investigator, unsuitable for the study including presence of any disease, abnormality, medical or physical condition that, in the opinion of the investigator, may adversely impact, compromise, interfere, limit, affect or reduce the safety of the subject, the integrity of the data ; Person protected by articles L1121-5, L1121-6 of Public Health Code (pregnant or breastfeeding woman, deprived of liberty by judicial decision, situations of social fragility, adults unable or unable to express their consent, person under judicial safeguard (article L1122-2)).

For healthy volunteers :

Inclusion criteria :

• Male or female of over 18 years of age
• IQ compatible with the realization of the study
• Patient able to understand, speak and write in French;
• Patient willing to participate, and gave written consent to the study after receiving clear information
• Subject beneficiary or affiliated to a health insurance plan

Exclusion criteria :

• Subject presenting any neurological or psychiatric illnesses.
• Subject having major visual impairment incompatible with the realization of neurofeedback, based on investigator's opinion.