EFFECTS OF METHADONE AND MORPHINE ON THE ELECTROENCEPHALOGRAM OF THE DOG

The present study was made as part of a comprehensive investigation of the comparative actions of methadone and morphine on the central nervous system (1, 2). The dog has been utilized in these studies because the effects of small doses of methadone and morphine on this species are analogous to those in man (3-5). In particular, however, we wished to compare the effects of large doses of methadone and morphine on the electroencephalogram since such studies can-not be made with safety in man. Some of the observations made in the course of these investigations are also of interest with reference to the pharmaco-phys-iologic aspects of convulsive seizures. METHODS. Electroencephalographic studies were made on eleven dogs. In eight of these animals the effects of methadone and morphine were observed without previous anaesthe-sia or curare. This was accomplished by the insertion of wire or “mercury cup ” electrodes which made contact with the dura over the desired cortical area. The mercury cup elec-trode (figure 1) was inserted under aseptic conditions and permitted the recording of dcc-troencephalograms without muscle artifacts in the same dog as often as desired over