Abstract
There is a limited amount of information available about taste as a discriminative stimulus in non-human primates. The objective of this study was to establish a bitter taste (quinine sulfate) as a cue for lever selection and food reward in rhesus monkeys. Training took place in a series of steps that culminated in a schedule in which five lip contacts on a spout produced either quinine solution or water, followed by an opportunity to earn a food pellet by completing 20 presses on one of two levers. Responses on one of the levers resulted in food delivery if the solution contained quinine; responses on the other lever resulted in food delivery if the solution was water. A single session consisted of 100 randomly ordered taste trials with a 60-s interval between each trial. All of the animals acquired the discrimination, and the lowest quinine concentration that maintained consistent behavior was 0.3 mg/ml. To assess the specificity of the discrimination, compounds from other human taste categories were tested. A series of compounds that are detected as ”bitter” by humans (caffeine, 1.5×10–3 M; strychnine, 9×10–4 M; PTC, 6×10–5 M, denatonium benzoate, 2.24×10–4 M; and urea, 3.0×10–1 M) produced full generalization to the quinine sulfate discriminative stimulus, while ”sweet” (sucrose, 2.9×10–2 M) and ”salty” (sodium chloride, 1.4 M) stimuli did not. There was individual variation among animals in response to ”sour” compounds; acetic acid did not generalize to quinine, but HCl acid produced full generalization in one of three animals. These results suggest that a ”bitter” taste cue is controlling the quinine discrimination.
Similar content being viewed by others
Author information
Authors and Affiliations
Additional information
Received: 3 February 1998 / Final version: 14 August 1998
Rights and permissions
About this article
Cite this article
Aspen, J., Gatch, M. & Woods, J. Training and characterization of a quinine taste discrimination in rhesus monkeys. Psychopharmacology 141, 251–257 (1999). https://doi.org/10.1007/s002130050832
Issue Date:
DOI: https://doi.org/10.1007/s002130050832