Motivation for alcohol in rats: position and bottle preferences do not cause drinking.

Position preference, i.e., the tendency to drink from onelocation rather than the other, was found to be relatively unimportant in determining the drinking behavior of rats presented with a choice between water and a 7% (v/v) ethanol solution in typical two-bottle choice situations. It accounted for essentially none of the variance in rats generally drinking more alcohol solution than water after prolonged previous alcohol experience, and in rats consuming very little alcohol; only in rats drinking slightly less alcohol solution than water was it found to have an influence. Similarly, bottle preference, i.e., the tendency to drink from one of the two bottles regardless of its position or contents, andposition preference were found to have almost no effect on heavy-drinking rats even on their first day of exposure and on low-drinking rats after about three days of access to alcohol.