Pattern of daily water consumption in relation to intake of saccharin solution

Abstract

Twelve nondeprived rats were presented with a bottle (B2) containing.25% saccharin solution for 1 h each day in addition to the maintenance water bottle (Bl). After 18 days (preshift), the contents of B2 were changed to plain tap water for 6 days (postshift). Intake from B1 in the 2 h preceding the time of B2 presentation increases during preshift while overnight intake decreased, suggesting the emergence of a B1 drinking schedule as intake from B2 increased. However, detailed aspects of the results were not consonant with this possibility. During postshift, intake from B1 returned to the initial preshift level while intake from B2 settled at a much higher level, suggesting the operation of secondary reinforcement.