whereby α4 subunit down-regulation in the shell may reduce the reinforcing effects of ethanol. For example, α4 subunit down-regulation may affect taste reactivity, such that acceptance of ethanol is decreased. It is also possible that our findings reflect alterations is neural systems critical for conditioned reinforcing properties of the sensory attributes of ethanol as learned indicators of subsequent pharmacological effects. Finally, it is always possible that decreases in responding reflect increases, rather than decreases, in rewarding properties that may result in faster satiation. Further experimentation is required to address these different possibilities.
