HUMAN ETHANOL SELF-ADMINISTRATION .1. THE INTERACTION BETWEEN RESPONSE REQUIREMENT AND ETHANOL DOSE

The effects of work requirement on human ethanol self-administration w ere systematically examined. Healthy volunteers with a history of mode rate alcohol consumption (12 to 16 drinks per week) were recruited as subjects. Four subjects self-administered 4, 8 or 16% w/v ethanol solu tion contingent upon completion of a fixed-ratio (FR) response require ment. The ratio requirements were FR 32, FR 64 and FR 128 responses. E thanol consumption at lower doses decreased with increases in FR. Etha nol consumption at the high dose was greatest across all ratio require ments and was unchanged by increases in the ratio requirement, indicat ing greater relative reinforcing effects of the high dose of ethanol. Ethanol consumption was sensitive to unit price with 53-82% of the var iance explained by the unit price analysis.