The Effects of Alcohol on Evoked Potentials of Various Parts of the Central Nervous System of the Cat

Abstract

The actions of alcohol 011 the electrical activity of the cortex and deep structures of the brain in various animals have been the subject of investigations by many workers. Included in these studies are the contributions of Horsey and Akert (1953) and Caspers (1958), who worked on animals. Alcohol permeates the brain readily, and there appears to be no doubt that alcohol in adequate doses depresses the functions of the central nervous system. The effects of small doses of alcohol are less clear but evidence is in favor of a transient excitatory stage in electroencephalographic (EEG) activity (Horsey and Akert, 1953; Masserman, 1940). There is general agreement that alcohol has a synchronizing effect on the spontaneous electrical activity of the cerebral cortex and, depending on the dose, that such activity shows varying degrees of reduction in frequency and decreases in amplitude. In a comprehensive review, Kalant (1961) quotes Caspers (1958) who worked on rats and furthered the idea that alcohol exerts its earliest effect at the level of the reticular formation and that changes in electrical cortical activity are secondary to the primary reticular depression. However, this viewpoint has been questioned by several investigators (Himwich et al., 1966; DiPerri et al., 1968) and it will be discussed in detail later in the chapter. The reticular formation, as defined by Moruzzi and Magoun (1949), has been shown to play an important role in modifying sensory patterns (Hernández-Peon et al., 1956, 1957; Killam, 1962; Steriade and Demetrescu, 1962; Chin et al., 1965).