Equal-reinforcement values for sucrose and glucose solutions compared with equal-sweetness values.

Abstract

Sucrose and glucose solutions from 2% to 32% concentration were used as reward for rats in the aperiodically reinforced bar-pressing situation. Rate of bar-pressing was an increasing, nearly logarithmic function of concn. for both substances, with the rate for glucose always below that for the same concn. of sucrose. Below 20% glucose, the glucose-sucrose concentration pairs which yield equal response rates correspond to the concn. pairs judged equally sweet by human subjects. The rate-concn. curves extrapolate approximately to origins at the respective human absolute thresholds. The relationships obtained indicate a close connection between reinforcement values and taste-receptor effects.