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Mauricio R. Papini - One of the best experts on this subject based on the ideXlab platform.
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control of free choice Consummatory Behavior by absolute reward value
Learning and Motivation, 2020Co-Authors: Sara Guarino, Shannon E. Conrad, Mauricio R. PapiniAbstract:Abstract Rats trained in a 2-lever autoshaping situation with large and small rewards, prefer the lever signaling the large reward in simultaneous free-choice tests. However, after a large-to-small reward devaluation, choice switches to the unshifted lever that always offered the small reward ( Conrad & Papini, J Exp Psychol: Anim Learn Cog, 2018 ). Such revaluation of an option signaling an unshifted reward in a choice situation illustrates reward relativity. Would a similar reward revaluation be observed in Consummatory Behavior? In Experiment 1, two groups of rats received exposure to 16% vs. 2% or 4% vs. 2% sucrose in different bottles. Free-choice tests with the simultaneous presentation of both bottles showed that preference for the large reward was greater in 16-vs.−2% than in 4-vs.−2% sucrose comparisons. After the downshift, free-choice responses adjusted in both groups without a switch in preference to the unshifted option (i.e., no evidence of revaluation). Experiment 2 replicated the training procedure, but free-choice tests were administered on a separate session with empty bottles. In free-choice tests, rats showed a reduction of responding for the downshifted bottle with no evidence of revaluation of the unshifted reward. In Experiment 3, sessions with the large (16% or 4% sucrose) and small reward (2% sucrose) occurred in the same context, but at different times. Free-choice tests again provided no evidence of revaluation. Consummatory Behavior is usually quite sensitive to reward relativity, but free choices uncovered strong control by absolute reward value.
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Dimensions of sucrose solutions in the successive negative contrast effect
Learning and Motivation, 2020Co-Authors: Juan Carlos Ruiz-salas, L. Gonzalo De La Casa, Mauricio R. PapiniAbstract:Abstract The Consummatory successive negative contrast (cSNC) task typically involves administering food-deprived rats 10 daily 5-min sessions of access to 32 % sucrose (preshift) followed by a few sessions in which the concentration is reduced to 4 % sucrose (postshift). Such sucrose downshift leads to transient suppression of Consummatory Behavior. Reward downshifts were used to determine whether food-deprived rats treat sucrose solutions as food, because sweetness is a proxy for its caloric content, or as water, because a solution has hydration content. In Experiment 1, a cSNC effect was obtained in food-deprived animals, but not in water-deprived animals. This suggested that food deprivation focused attention on the feeding dimension of sucrose, whereas water deprivation focused attention on the drinking dimension of sucrose. Sucrose downshift results in a greater caloric change than in hydration content because both concentrations continue to provide fluid. Experiments 2 and 3 offered presession access to rewards either before preshift or before postshift sessions, respectively. Consistent with this attentional view, presession access to water (which should focus attention on the feeding dimension), but not to food (which should focus attention on the drinking dimension), suppressed Consummatory Behavior after a sucrose downshift. Presession access to food, like water deprivation, enhanced the hydration properties of the sucrose solution at the expense of its caloric properties. These results are consistent with an attentional hypothesis according to which the internal state, manipulated via deprivation or presession reward access, determines which dimension of the sucrose reward would control Consummatory Behavior.
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Complex effects of reward upshift on Consummatory Behavior.
Behavioural Processes, 2016Co-Authors: Iván Annicchiarico, Amanda C. Glueck, Lucas Cuenya, Katsuyoshi Kawasaki, Shannon E. Conrad, Mauricio R. PapiniAbstract:Exposing rats to an upshift from a small reward to a larger reward sometimes yields evidence of Consummatory successive positive contrast (cSPC), an effect that could be a suitable animal model of positive emotion. However, cSPC is an unreliable effect. Ten experiments explored the effects of an upshift in sucrose or saccharin concentration on Consummatory Behavior under several conditions. There was occasional evidence of cSPC, but mostly a combination of increased Consummatory Behavior relative to preshift reward concentrations and a reduced Behavioral level relative to unshifted controls. Such a pattern is consistent with processes causing opposite changes on Behavior. Reward upshift may induce processes that suppress Behavior, such as taste neophobia (induced by an intense sucrose taste) and generalization decrement (induced by novelty in reward conditions after the upshift). An experiment tested the role of such novelty-related effects by preexposing animals to either the upshift concentration (12% sucrose) or water during three days before the start of the experiment. Sucrose-preexposed animals drank significantly more than water-preexposed animals during the upshift, but just as much as unshifted controls (i.e., no evidence of cSPC). These results suggest that cSPC may be difficult to obtain reliably because reward upshift induces opposing processes. However, they also seriously question the ontological status of cSPC.
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Anisomycin Disrupts Consummatory Behavior after Incentive Downshift via Conditioned Taste Aversion
International journal of psychology and psychological therapy, 2014Co-Authors: Leonardo A. Ortega, Amanda C. Glueck, Mauricio R. PapiniAbstract:The protein synthesis inhibitor anisomycin was tested in the Consummatory successive negative contrast paradigm (cSNC). The cSNC effect involves suppression of Consummatory Behavior induced by 4% sucrose in animals that previously received 32% sucrose (downshifted), relative to animals that always received 4% sucrose (unshifted). Systemic anisomycin (25 mg/kg, ip) induced suppression in both downshifted and unshifted groups when injected before the first or second downshift trial (Experiment 1) or after the first downshift trial (50 mg/kg, ip; Experiment 2). The effect of anisomycin (50 mg/kg, sc) administration after the first downshift trial was observed only in downshifted animals in Experiment 3, but the same dose and route of administration induced significant conditioned taste aversion in Experiment 4. It was concluded that a conditioned taste aversion to the 4% sucrose solution accounts most parsimoniously for all the results. Implications for other experiments involving posttrial anisomycin administration are discussed.
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Effects of pretraining treatment with testosterone on successive and anticipatory negative contrast.
Physiology & Behavior, 2012Co-Authors: Nadia Justel, Alba Elisabeth Mustaca, Eliana Ruetti, Mauricio R. PapiniAbstract:Previous research indicated that the suppression of Consummatory Behavior that follows incentive downshift in male rats is attenuated by testosterone (T) administration during training. The present experiments were designed to assess the role of pretraining T administration on two incentive contrast situations in Consummatory Behavior: successive negative contrast (cSNC) and anticipatory negative contrast (cANC). In cSNC (Experiment 1), a downshift from 32% to 4% sucrose leads to Behavioral suppression relative to an unshifted, 4% sucrose condition (the cSNC effect). Pretraining T administration enhanced Consummatory Behavior directed at 4% sucrose, without affecting Behavior directed at 32% sucrose. This effect obscured a reduction in the cSNC effect by the T treatment that was only detected when a proportional measure of Behavior was used. In cANC (Experiment 2), groups received access to two bottles per day separated by a short midtrial interval. Consumption of 4% sucrose is suppressed when the second bottle offers 32% sucrose, relative to 4% sucrose (the cANC effect). Pretraining T did not affect the cANC effect, known to be insensitive to treatment with anxiolytics. These results suggest an anxiolytic-like effect of testosterone in adjustment to incentive downshifts.
Santiago Pellegrini - One of the best experts on this subject based on the ideXlab platform.
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Stimulus magnitude effects on the extinction of conditioned Consummatory responses to flavored sucrose solution in mice.
Behavioural Processes, 2011Co-Authors: Santiago PellegriniAbstract:Paradoxical extinction effects in the conditioned Consummatory Behavior of rodents have remained largely elusive. Here, appetitive flavor conditioning was studied to determine if a paradoxical magnitude of reinforcement extinction effect (MREE) can occur in the Consummatory Behavior of mice. During acquisition training of two experiments with factorial design, animals received daily access to either 32% or 4% sucrose solution, and goal tracking time was measured in one-minute bins. In Experiment 1 the solutions were flavored with either 5% or 0.5% almond essence and in Experiment 2 with 2% almond essence, but combined with continuous or partial schedules of reinforcement. During extinction tests of Experiment 1 and 2, water flavored with 0.5% or 2% almond was presented, respectively. Consummatory performance decreased more abruptly during the initial portion of the extinction sessions after training with 32% as compared to 4% sucrose solution. Furthermore, when given a choice test after extinction training (Experiment 2), animals trained with 32% sucrose, preferred the flavored solution, but animals trained with 4% preferred the unflavored solution. These results are interpreted as indicative of the occurrence of a paradoxical MREE in conditioned Consummatory Behaviors.
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Scaling relative incentive value in anticipatory Behavior
Learning and Motivation, 2007Co-Authors: Santiago Pellegrini, Mauricio R. PapiniAbstract:Abstract Papini and Pellegrini (Papini, M. R., & Pellegrini, S. Scaling relative incentive value in Consummatory Behavior. Learning and Motivation, in press) observed that, within limits, the level of Consummatory responding of rats exposed to incentive downshifts in the concentration of sucrose solutions was similar when the ratio of test/training solutions was the same. For example, 32 → 4% and 16 → 2% downshifts (1:8 test/training ratios) lead to similar levels of Consummatory Behavior, despite differences in the absolute concentrations of the solutions involved in the downshift. This suggests the applicability of Weber’s law to spaced-trial, incentive-downshift situations. Experiment 1 extended these results to runway performance using food pellets as reward, and Experiment 2 to lever pressing performance, using an autoshaping procedure and sucrose solutions as rewards. The results conform well to the test/training ratio suggesting that Weber’s law is applicable to anticipatory Behavior. A simple mathematical rule that can be easily incorporated into models based on linear operators describes the results of Consummatory and anticipatory Behavior experiments.
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Scaling Relative Incentive Value in Consummatory Behavior.
Learning and Motivation, 2006Co-Authors: Mauricio R. Papini, Santiago PellegriniAbstract:Abstract Surprising downshifts from more preferred (training incentive) to less preferred incentives (test incentive) are usually accompanied by emotional activation and suppression of conditioned Behavior in rats. Two experiments were designed to determine whether Consummatory Behavior is similarly affected by downshifts of equal proportions. Within limits, the degree of Consummatory responding during incentive downshift was similar with equal ratios of test concentration to training concentration. Thus, 32–4% and 16–2% downshifts (1:8 test/training ratios) caused similar levels of Consummatory Behavior, despite differences in the absolute concentrations of the solutions involved in the downshift. An interpretation based on sensory contrast was discarded because of the long intervals between training and test solutions (40 min and 24 h in Experiments 1 and 2, respectively). It is suggested that Weber’s law regulates Behavioral suppression after reward downshifts. A theoretical framework for the interpretation of these data is presented.
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successive negative contrast after partial reinforcement in the Consummatory Behavior of rats
Learning and Motivation, 2004Co-Authors: Santiago Pellegrini, Alba Elisabeth Mustaca, Ruben N Muzio, Mauricio R. PapiniAbstract:Abstract Rats given access to a 32% sucrose solution later reject a 4% solution significantly more than controls that have only received the 4% solution. In Experiment 1, this Consummatory successive negative contrast (cSNC) effect was attenuated by previous exposure to 50% partial reinforcement. Furthermore, recovery from cSNC was also facilitated by partial reinforcement. In Experiment 2, the attenuating effects of partial reinforcement on cSNC were eliminated by administration of the benzodiazepine anxiolytic chlordiazepoxide (5 mg/kg) before nonreinforced trials. In Experiment 3, the attenuating effect of partial reinforcement was greater after a shift from 32 to 6% solution, than after a shift from 32 to 2% solution. The parallels between the effects of partial reinforcement on Consummatory and instrumental Behavior are discussed.
Allen S. Levine - One of the best experts on this subject based on the ideXlab platform.
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Oxytocin as feeding inhibitor: maintaining homeostasis in Consummatory Behavior.
Pharmacology Biochemistry and Behavior, 2010Co-Authors: Pawel K. Olszewski, Anica Klockars, Helgi B. Schiöth, Allen S. LevineAbstract:Initial studies showed that the anorexigenic peptide oxytocin (OT) regulates gastric motility, responds to stomach distention and to elevated osmolality, and blocks consumption of toxic foods. Most recently, it has been proposed to act as a mediator of general and carbohydrate-specific satiety and regulator of body weight. In the current review, we discuss the function of OT as a homeostatic inhibitor of consumption, capable of mitigating multiple aspects of ingestive Behavior and energy metabolism.
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Minireview: Characterization of Influence of Central Nociceptin/Orphanin FQ on Consummatory Behavior
Endocrinology, 2004Co-Authors: Pawel K. Olszewski, Allen S. LevineAbstract:Nociceptin/orphanin FQ (N/OFQ), a peptide closely related to dynorphin A, is the endogenous agonist of the NOP receptor that moderately increases food intake under various conditions. Its orexigenic properties are mediated by the brain circuitry. In the present review, we focus on discussing the nature of hyperphagic effects of N/OFQ with special emphasis on its function within feeding-related neural networks. Although some of N/OFQ’s orexigenic effects resemble those induced by opioids, reward-dependent feeding appears to be affected in a different manner by agonists of the NOP and classical opioid receptors. Also, data suggest that N/OFQ may not only promote feeding initiation, but rather its role may be to inhibit signaling responsible for inhibition of Consummatory Behavior. Central systems involved in termination of feeding that seem to be influenced by N/OFQ encompass oxytocin, α-MSH, and CRH.
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minireview characterization of influence of central nociceptin orphanin fq on Consummatory Behavior
Endocrinology, 2004Co-Authors: Pawel K. Olszewski, Allen S. LevineAbstract:Nociceptin/orphanin FQ (N/OFQ), a peptide closely related to dynorphin A, is the endogenous agonist of the NOP receptor that moderately increases food intake under various conditions. Its orexigenic properties are mediated by the brain circuitry. In the present review, we focus on discussing the nature of hyperphagic effects of N/OFQ with special emphasis on its function within feeding-related neural networks. Although some of N/OFQ’s orexigenic effects resemble those induced by opioids, reward-dependent feeding appears to be affected in a different manner by agonists of the NOP and classical opioid receptors. Also, data suggest that N/OFQ may not only promote feeding initiation, but rather its role may be to inhibit signaling responsible for inhibition of Consummatory Behavior. Central systems involved in termination of feeding that seem to be influenced by N/OFQ encompass oxytocin, α-MSH, and CRH.
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Effect of peptide histidine isoleucine on Consummatory Behavior in rats
American Journal of Physiology-Regulatory Integrative and Comparative Physiology, 2003Co-Authors: Pawel K. Olszewski, Michelle M. Wirth, Timothy J. Shaw, Martha K. Grace, Allen S. LevineAbstract:Peptide histidine isoleucine (PHI) and VIP are derived from the same precursor. While central VIP decreases food intake, potential effects of PHI on feeding have not been studied. In the current study, we found that PHI administered intracerebroventricularly (ICV) or into the hypothalamic paraventricular nucleus (PVN) or central nucleus of the amygdala (CeA) decreased food consumption in overnight-deprived rats. The magnitude of an anorexigenic response to PHI differed depending on the injection route: ICV-infused peptide evoked the most potent effect. We determined that that only PVN- and CeA-injected PHI did not have aversive consequences. In addition, we infused anorexigenic doses of PHI via the same routes and assessed Fos immunoreactivity of PVN oxytocin (OT) and vasopressin (VP) neurons using double immunohistochemistry. OT and VP are thought to promote feeding termination. PHI increased the percentage of Fos-positive OT neurons regardless of the injection route. PVN- and ICV-infused PHI induced activation of VP cells. We conclude that central PHI has an inhibitory influence on food intake in rats. The PVN, with OT and VP neurons, and CeA may be involved in the mediation of anorexigenic effects of PHI.
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Role of α-MSH in the regulation of Consummatory Behavior: immunohistochemical evidence
American Journal of Physiology-Regulatory Integrative and Comparative Physiology, 2001Co-Authors: Pawel K. Olszewski, Charles J. Billington, Michelle M. Wirth, Timothy J. Shaw, Martha K. Grace, Silvia Q. Giraudo, Allen S. LevineAbstract:Central injection of α-melanocyte-stimulating hormone (α-MSH) decreases food intake, suggesting a role for this peptide in the mediation of satiety. Inasmuch as α-MSH also supports the development ...
Martha Levinson - One of the best experts on this subject based on the ideXlab platform.
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interaction of msg taste with nutrition perspectives in Consummatory Behavior and digestion
Physiology & Behavior, 1991Co-Authors: Michael Naim, Ikuo Ohara, Morley R Kare, Martha LevinsonAbstract:Studies in the taste system of mammals indicate that monosodium glutamate (MSG) produces a unique taste sensation termed umami. As a derivative of glutamic acid, MSG is a naturally occurring nutrient in many foods; its commercial use to improve food palatability for humans is well documented. Behavioral studies with experimental animals have revealed that preference for MSG in solutions and selection of MSG-flavored diets can be explained by sensory means with no appreciable effects on preference by postingestive consequences. However, preference for umami-flavored fluids is reduced by feeding rats low-protein diets or low quality protein. MSG-flavored diets, initially unpreferred, were subsequently highly selected. However, the adulteration of diets by MSG either did not or only slightly increased food intake. In light of the significant contribution of MSG to diet taste, apparently as a signal coupled to dietary proteins, physiological studies have been initiated to reveal its role as a stimulator of the cephalic phase of pancreatic exocrine secretion. Modified sham-feeding experiments with dogs have shown that oral stimulation by MSG produced significant stimulation of both pancreatic flow and protein output in conscious dogs.
Michael Naim - One of the best experts on this subject based on the ideXlab platform.
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interaction of msg taste with nutrition perspectives in Consummatory Behavior and digestion
Physiology & Behavior, 1991Co-Authors: Michael Naim, Ikuo Ohara, Morley R Kare, Martha LevinsonAbstract:Studies in the taste system of mammals indicate that monosodium glutamate (MSG) produces a unique taste sensation termed umami. As a derivative of glutamic acid, MSG is a naturally occurring nutrient in many foods; its commercial use to improve food palatability for humans is well documented. Behavioral studies with experimental animals have revealed that preference for MSG in solutions and selection of MSG-flavored diets can be explained by sensory means with no appreciable effects on preference by postingestive consequences. However, preference for umami-flavored fluids is reduced by feeding rats low-protein diets or low quality protein. MSG-flavored diets, initially unpreferred, were subsequently highly selected. However, the adulteration of diets by MSG either did not or only slightly increased food intake. In light of the significant contribution of MSG to diet taste, apparently as a signal coupled to dietary proteins, physiological studies have been initiated to reveal its role as a stimulator of the cephalic phase of pancreatic exocrine secretion. Modified sham-feeding experiments with dogs have shown that oral stimulation by MSG produced significant stimulation of both pancreatic flow and protein output in conscious dogs.