[Influence of psychotropic substances on the self stimulation response]

D-amphetamine and cocaine were found to facilitate septal self-stimulation. In low doses morphine, imipramine, benactyzine, meprobamat, diazepam, chlordiazepoxide, phenobarbital, LSD-25 failed to influence this index, but in high doses they depressed the self-stimulation. It is supposed that d-amphetamine and cocaine exerted a direct stimulating action of the positive reinforcement system of the septum. Inefficiency of the other above-mentioned agents was due to the absence of the nervous substrate of negative reinforcement at the septum level. A comparative study of the above results and the influence of neurotropic agents on the hypothalamic self-stimulation (literature data) indicated that the activating effect of psychotropic agents on the systems of positive reinforcement depended upon their influence on the emotiogenic brain structures and not on the structures responsible for the formation of motivations.