Mild ethanol intoxication may enhance pavlovian conditioning

Abstract

Evidence is reviewed showing that low doses of ethanol (-200-400 mgikg), administered prior to training, can facilitate aversive Pavlovian conditioning and delay subsequent extinction of Pavlovian conditioned responses in both rabbits and rats. The effect of ethanol during Pavlovian training occurs during later testing in both intoxicated and sober animals and is stronger for Pavlovian than for comparable instrumental conditioned responses. New data are reported showing that the facilitatory effect of ethanol on Pavlovian conditioned suppression in rats interacts with both the extent of Pavlovian training and the reinforcement schedule used to maintain the operant baseline but also resembles the effect of more extended Pavlovian training in saline-treated animals. Together, these findings suggest that facilitation of Pavlovian conditioning may be a general effect of mild ethanol intoxication. Possible behavioral mechanisms of this effect are discussed.

Interactive effects of ethanol and nicotine on learning in C57BL/6J mice depend on both dose and duration of treatment

“…In the current study, we found, as have other researchers (Gulick and Gould 2007;Hernandez and Powell 1986;Hernandez and Valentine 1990), that low doses of ethanol enhance learning. Although there were no additive effects of nicotine withdrawal and high doses of ethanol on disruption of contextual fear conditioning, nicotine-withdrawal-associated deficits in contextual fear conditioning were reversed by a low dose of ethanol.…”

“…If such additive effects exist, they may contribute to the difficulty alcoholics experience in abstaining from nicotine. Moreover, it has been demonstrated that low doses of ethanol enhance learning (Gulick and Gould 2007;Hernandez and Powell 1986;Hernandez and Valentine 1990); thus, a dose of ethanol that enhances learning could reverse nicotine withdrawal deficits.…”

Acute Ethanol Has Biphasic Effects on Short‐ and Long‐Term Memory in Both Foreground and Background Contextual Fear Conditioning in C57BL/6 Mice

“…Ethanol‐induced changes in NMDA receptor function could also explain the enhancement of fear conditioning by ethanol. Similar to the present results for fear conditioning, prior research demonstrates that ethanol enhances other forms of learning including eye blink conditioning (Devenport et al., 1983; Hernandez and Powell, 1986; Hernandez and Valentine, 1990; Korman et al., 1960). What is interesting is that eye blink conditioning involves plasticity in the cerebellum (Gould and Steinmetz, 1996; Kim and Thompson, 1997; McCormick and Thompson, 1984), while fear conditioning involves plasticity in the hippocampus and amygdala (Kim et al., 1993; Le Doux, 1995; Logue et al., 1997; Phillips and LeDoux, 1992); yet although the underlying neural areas involved in eye blink conditioning differ from those involved in fear conditioning, the dose of ethanol that enhanced fear conditioning was within the range of doses that enhanced eye blink conditioning.…”

“…Far fewer studies have examined the effects of low doses of ethanol on cognition. The studies that have been conducted suggest that lower doses of ethanol may enhance learning in paradigms such as the 8‐arm radial maze, serial learning during stress, and eye blink conditioning (Devenport et al., 1983; Hernandez and Powell, 1986; Hernandez and Valentine, 1990; Korman et al., 1960). To date, no studies have examined the effects of ethanol on fear conditioning using both doses that have been shown to enhance learning in other studies and doses associated with impairments.…”

Role of hippocampus in alcohol-induced memory impairment: implications from behavioral and immediate early gene studies

“…Interestingly, these studies also showed that very low doses of alcohol (0.375 g/kg) enhanced conditioning, suggesting two important points: first, that the effects of alcohol on memory are dose-dependent, and second, that learning in different paradigms, possibly involving divergent neuronal populations, may be differentially affected by alcohol (Hernandez and Valentine 1990). Although initially these tasks were considered hippocampus-independent, more and more recent studies show hippocampal involvement in passive avoidance learning (Lorenzini et al 1996;Stecher et al 1997;Treit and Menard 1997) and in eye-blink conditioning (Akase et al 1989;Moyer et al 1990;Woodruff-Pak et al 1997).…”