Investigation of the devaluation interpretation of anticipatory negative contrast.

Abstract

Rats suppress intake of an acceptable substance (e.g., 0.15% saccharin) when it is followed by a preferred substance (e.g., 32% sucrose) in once per day pairings. The role of a learned devaluation of the initial solution in suppressed intake (anticipatory negative contrast) was investigated. The findings included the following: (a) Flavors or odors as within-subject cues precluded the occurrence of anticipatory contrast, conditioning flavor and odor preferences instead, which appeared to antagonize suppressed intake. (b) Anticipatory contrast was obtained when within-subject context cues, temporal alternation cues, or drinking-spout cues were used. (c) Preference tests conducted with the spout cues showed that devaluation of the initial substance was not necessary for the occurrence of negative anticipatory contrast.

Opioid-Dependent Anticipatory Negative Contrast and Binge-Like Eating in Rats with Limited Access to Highly Preferred Food

“…Studies were not designed to distinguish the mechanisms responsible for reductions in home-cage or predeprivation chow intake. However, several findings support the interpretation that chow hypophagia at the first feeder was a form of anticipatory negative contrast (Flaherty and Checke, 1982;Flaherty and Rowan, 1986;Flaherty et al, 1995) and not energy homeostatic compensation for accruing weight gain, lasting satiety, or successive negative contrast. First, there was no concurrent or prospective relation between differences in weight gain and the magnitude of chow hypophagia (unlike strong individual differences seen in chow hypophagia).…”

“…Anticipatory negative contrast has been interpreted alternatively as: devaluation (whereby the hedonic value of the first tastant is decreased as a result of historical or representational comparisons to a more preferred tastant), inhibition (whereby rats learn that a more preferred tastant is imminent and correspondingly inhibit intake of a less preferred, predictive, tastant), or behavioral competition (whereby conditioned anticipatory behavior interferes with ingestion of the first tastant) (Flaherty et al, 1995). Although the present data do not clearly differentiate between these interpretations, they suggest a hedonic, non-energy homeostatic account of anticipatory negative contrast.…”

“…Such a learned change in food acceptance may increase risk for body weight dysregulation and eating disorders because of the increased role placed on sensoryhedonic, rather than nutritional, properties of food for controlling intake (Wardle et al, 2001). Perhaps an analog of this learned change in food acceptance, negative contrast in rodents refers to the hypophagia of an otherwise acceptable tastant that results from having predictably received access to a more preferred substance either immediately before (successive negative contrast) or subsequent to (anticipatory negative contrast) that substance (Flaherty and Checke, 1982;Flaherty and Rowan, 1986;Flaherty et al, 1995). Contrast effects have been studied previously using limitedly available (3-5 min) sweet solutions in weight-restricted rats, but have not yet been well-studied vis-à-vis day-to-day food acceptance/intake in subjects' self-determining body weight.…”

“…Nalmefene was predicted to normalize successive intake of the otherwise differently preferred diets, reducing chow intake in subjects that had not experienced more preferred food options, but increasing intake of less-preferred chow in palatable food-experienced subjects. This novel, second prediction is based on findings that (1) binge-like eating and anticipatory negative contrast are palatability-induced adaptations of eating behavior (Corwin, 2006;Flaherty et al, 1995) and that (2) opioid-receptor antagonists dull palatability-related processes (Cooper, 2004;Yeomans and Gray, 2002).…”

Effects of neuropeptide Y on feeding microstructure: Dissociation of appetitive and consummatory actions.

“…Rats were offered the same sucrose concentration for 5 consecutive test days, with ICV injections on Days 3 and 5. This approach served to avoid potential contrast effects (Flaherty, Coppotelli, Grigson, Mitchell, & Flaherty., 1995) and ensure stable baseline intake responses. Two rest days intervened between 5-day concentration test blocks.…”