Reduced palatability in pain-induced conditioned taste aversions

• Published in: Physiology & behavior Vol. 119; pp. 79 - 85
• Main Authors: Lin, Jian-You, Arthurs, Joe, Reilly, Steve
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Inc 02.07.2013; Elsevier
• Subjects: Animals; Avoidance Learning - drug effects; Behavioral psychophysiology; Biological and medical sciences; Conditioning, Classical; Feeding Behavior - drug effects; Fundamental and applied biological sciences. Psychology; Gallamine; Gallamine Triethiodide - pharmacology; Hypertonic sodium chloride; Lick cluster size; Lithium chloride; Male; Medical sciences; Neuropharmacology; Pain - chemically induced; Pain - psychology; palatability; Pharmacology. Drug treatments; Psychiatry; Psychoanaleptics: cns stimulant, antidepressant agent, nootropic agent, mood stabilizer; Psychoanaleptics: cns stimulant, antidepressant agent, nootropic agent, mood stabilizer..., (alzheimer disease); Psychology. Psychoanalysis. Psychiatry; Psychology. Psychophysiology; Psychopharmacology; Rats; saccharin; Saccharin - pharmacology; Saline Solution, Hypertonic - pharmacology; sodium chloride; Taste; Rats; Lick cluster size; Gallamine; Lithium chloride; Hypertonic sodium chloride; Non depolarizing muscle relaxant; Rat; Rodentia; Gallamine triethiodide; Lithium; Gustative system; Sodium chloride; Vertebrata; Mammalia; Pain; Mood stabilizer; Gustation; Animal; Taste; Conditioned aversion
• ISSN: 0031-9384; 1873-507X
• DOI: 10.1016/j.physbeh.2013.06.012

Abstract The current study investigated whether internal pain-inducing agents can modulate palatability of a tastant in the same way as illness-inducing agents (e.g., lithium chloride). Similar to traditional conditioned taste aversion (CTA) experiments, during conditioning the rats were exposed to a saccharin solution followed by intraperitoneal injections of either gallamine (Experiment 1) or hypertonic sodium chloride (NaCl; Experiments 1 and 2). In addition to the total amount consumed, the time of each lick was recorded for lick pattern analysis. The results showed that both gallamine and hypertonic NaCl caused suppression in saccharin intake. Importantly, both lick cluster size and initial lick rate (the measures of taste palatability) were reduced as well. This pattern of results suggests that these pain-inducing agents reduce the hedonic value of the associated tastant and thus CTA is acquired. The current finding serves as evidence supporting the view that CTA is a broadly tuned mechanism that can be triggered by changes in internal body states following consummatory experience.