In the present study, we investigated the different types of neocortical rhythmic slow activity (RSA) during wakefulness and paradoxical sleep as well as their pharmacological modification. During wakefulness, the high-frequency (7-9 Hz) RSA1 type, which is atropine-resistant, is accentuated by forebrain stimulation and is abolished by urethane, clonidine and alcuronium. These drugs induce the...