[Biofeedback and drug-resistant epilepsy: back to an earlier treatment?].

Biofeedback is a complementary non-pharmacological and non-surgical therapeutic developed over the last thirty years in the management of drug-resistant epilepsy. Biofeedback allows learning cognitive and behavioral strategies via a psychophysiological feedback loop. Firstly, this paper describes the different types of biofeedback protocols used for the treatment of drug-refractory epilepsy and their physiological justifications. Secondly, this paper analyzes the evidence of effectiveness, from a medical point of view, on reducing the numbers of seizures, and from a neurophysiological point of view, on the changing brain activity. Electroencephalography (EEG) biofeedback (neurofeedback) protocol on sensorimotor rhythms (SMR) has been investigated in many studies, the main limitation being small sample sizes and lack of control groups. The newer neurofeedback protocol on slow cortical potential (SCP) and galvanic skin response (GSR) biofeedback protocols have been used in a smaller number of studies. But, these studies are more rigorous with larger sized samples, matched control groups, and attempts to control the placebo effect. These protocols also open the way for innovative neurophysiological researches and may predict a renewal of biofeedback techniques. Biofeedback would have legitimacy in the field of clinical drug-resistant epilepsy at the interface between therapeutic and clinical neurophysiology.