The programming details of the induction phase include the designation of 3 experimental “States” for each session, imposed to separate the induction of ethanol drinking from the consumption of water and food later in the daily session. In “State 1” (scheduled-induced polydipsia) a food pellet was given every 300 seconds until the predetermined amount of fluid was consumed (or the daily food ration of pellets was delivered). “State 2” then ensued without pellet delivery and only vehicle (water) was available for 2 hours. However, if the induced dose of ethanol was not consumed in state 1 (an occurrence that would also indicate the entire daily food ration had been delivered under the fixed-time schedule), then ethanol remained the only fluid available in state 2 (this occurred in 5/900 or <0.5% of total ethanol induction sessions). “State 3” then began and any remaining pellets (daily ration minus pellets delivered under the fixed-time schedule) were available under a fixed ratio of 1 pellet for each press on the push panel. Water was also available. The preset volume of the induced fluid was completely consumed in either state 1 or state 2 in all, but 1 monkey on 1 day.
The main correlate of current study is daily ethanol intake (g/kg) during the 12-months of ethanol self-administration for 22 h/d (further details and characteristics of the 12 months of chronic ethanol self-administration to be published separately). Two sets of exploratory analyses, namely, principal components regression analysis (PCRA) and classification based on functional principal components analysis (FPCA), were performed to determine whether drinking behaviors on different induction doses (water, 0.5, 1.0, and 1.5 g/kg sessions) predict chronic alcoholic binge-drinker during 22-hour self-administration.
The main correlate of current study is daily ethanol intake (g/kg) during the 12-months of ethanol self-administration for 22 h/d (further details and characteristics of the 12 months of chronic ethanol self-administration to be published separately). Two sets of exploratory analyses, namely, principal components regression analysis (PCRA) and classification based on functional principal components analysis (FPCA), were performed to determine whether drinking behaviors on different induction doses (water, 0.5, 1.0, and 1.5 g/kg sessions) predict chronic alcoholic binge-drinker during 22-hour self-administration.