Inclusion Criteria:  For the patient group:  age >18, <65 newly diagnosed, drug naive patients with primary restless legs syndrome  For the control group:  age >18, <65 participants without chronic systemic disorder  Exclusion Criteria:  previous diagnosis of primary RLS subjects with secondary RLS concomitant use of drugs that could interfere with autonomic nervous system individuals with a known acute/chronic medical disease individuals with a minimental test score < 25/30 sleep disorders that could affect test performances