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Floresco S B - - 2008
Reinstatement of previously extinguished instrumental responding for drug-related cues has been used as an animal model for relapse of drug abuse, and is differentially affected by inactivation of the core and shell subregions of the nucleus accumbens (NAc). To compare the roles of these subregions in reinstatement induced by cues ...
Bezzina G - - 2008
Previous experiments showed that destruction of the orbital prefrontal cortex (OPFC) or the nucleus accumbens core (AcbC) in rats altered choice between two delayed food reinforcers. Application of a quantitative model of inter-temporal choice suggested that lesions of either structure increased the delay-dependent degradation of reinforcer value (delay discounting); destruction ...
Williams Douglas A - - 2008
Analyses of second-by-second conditioned responding into a food receptacle by hungry rats (Rattus norvegicus) found that inhibition varies across the duration of a conditioned stimulus (CS) in a manner consistent with initial training. Variations in the arrival time of the unconditioned stimulus (US) supported temporally specific suppression of responding (Experiment ...
Sunsay Ceyhun - - 2008
To assess the role of dopamine input to the nucleus accumbens core in anticipatory learning, fast-scan cyclic voltammetry was combined with appetitive Pavlovian conditioning. One group of rats (Paired) received 16 tone-food pairings for at least four daily sessions while the control group (Unpaired) received the same number of unpaired ...
Christensen Chesley J - - 2008
RATIONALE: To provide a prospective test of the predictive adequacy of the exponential model of demand (Hursh and Silberberg, Psych Rev 115(1):186-198, 2008). OBJECTIVES: In Experiment 1, to measure the 'essential value' (the propensity to defend consumption with changes in price) of cocaine and food in a demand analysis (functional ...
Aparicio Carlos F - - 2008
Recent research has examined the effects on behavioral adjustment of a range of within-session changes in the reinforcer ratio available from two alternatives. Regularities between extended patterns of behavior (choice) and a distribution of food deliveries (expressed as a food-rate ratio) have emerged from such studies. To assess the generality ...
Ploog Bertram O - - 2008
A modified autoshaping paradigm (significantly different from those previously reported in the summation literature) was employed to allow for the simultaneous assessment of stimulus summation and subtraction in pigeons. The response requirements and the probability of food delivery were adjusted such that towards the end of training 12 of 48 ...
Keiflin Ronald - - 2008
RATIONALE: The exact behavioral nature of drug-induced reinstatement of drug seeking is still debated. As an incentive, the drug can have general facilitatory influences on appetitive behaviors. As an interoceptive stimulus, the drug can acquire discriminative properties and control behavior. OBJECTIVE: This study assessed the relative contribution of the incentive ...
Rasmussen Erin B - - 2008
The hypothesis that a penny lost is valued more highly than a penny earned was tested in human choice. Five participants clicked a computer mouse under concurrent variable-interval schedules of monetary reinforcement. In the no-punishment condition, the schedules arranged monetary gain. In the punishment conditions, a schedule of monetary loss ...
Richardson Joseph V - - 2008
In three experiments, a rat's lever presses could postpone timeouts from food pellets delivered on response-independent schedules. In Experiment 1, the pellets were delivered at variable-time (VT) rates ranging from VT 0.5 to VT 8 min. Experiment 2 replicated the VT 1 min and VT 8 min conditions of Experiment ...
Covarrubias Pablo P Universidad de Guadalajara-CUCBA-Instituto de Neurociencias, Francisco de Quevedo 180, Arcos Vallarta 44130, Guadalajara, Mexico. - - 2008
The Mathematical Principles of Reinforcement (MPR) model accurately predicts performance in fixed ratio (FR) schedules of reinforcement. The aim of the present study was to assess the generality of MPR with rats responding under progressive ratio (PR) schedules of different step sizes (PR1 or PR3) that provided either food or ...
Sanabria Federico - - 2008
We propose a novel method to dissociate incentive motivation from memory and motor processes in instrumental performance. Components of a multiple fixed-ratio schedule of food reinforcement were adjusted to envelop the range of response requirements that maintained lever pressing by rats. We sought to manipulate motivation for food rewards with ...
Bell Matthew C - - 2008
The effect of signals on resistance to change was evaluated using pigeons responding on a three-component multiple schedule. Each component contained a variable-interval initial link followed by a fixed-time terminal link. One component was an unsignaled-delay schedule, and two were equivalent signaled-delay schedules. After baseline training, resistance to change was ...
Epstein Leonard H - - 2008
Reports an error in "Food reinforcement, the dopamine D-sub-2 receptor genotype, and energy intake in obese and nonobese humans" by Leonard H. Epstein, Jennifer L. Temple, Brad J. Neaderhiser, Robbert J. Salis, Richard W. Erbe and John J. Leddy (Behavioral Neuroscience, 2007[Oct], Vol 121[5], 877-886). In the original article, the ...
Raiff Bethany R BR Department of Psychology, University ofFlorida, Gainesville, Florida 32611-2250, USA. - - 2008
Four pigeons responded on a two-component multiple token-reinforcement schedule, in which tokens were produced according to a random-interval 30-sec schedule and exchanged according to a variable-ratio 4 schedule in both components. To assess the effects of contingent token loss, tokens were removed after every second response (i.e., fixed-ratio 2 loss) ...
Nair S G - - 2008
Many studies have demonstrated a role of hypocretin 1 (orexin 1) receptors in home-cage food consumption in rodents. However, the role of these receptors in operant food self-administration or relapse to food seeking in animal models is unknown. In Experiment 1, we trained food-restricted rats (16-20 g per day) to ...
Lombas Andrés S AS Facultad de Psicología, Universidad del País Vasco, Avenida de Tolosa, 70, 20018 San Sebastián, Spain. - - 2008
In two experiments, the effects of Pavlovian or discriminative conditioned inhibitors on operant responding were investigated in rats. Experiment 1 found that a Pavlovian conditioned inhibitor for food suppressed food-reinforced lever pressing more than a non-differentially trained control stimulus did. Experiment 2 demonstrated that an operant discriminative inhibitor produced greater ...
Kupfer Anne S - - 2008
Adjunctive or induced behavior is generated during a variety of schedules of reinforcement. Several theoretical conceptualizations suggest that rate of reinforcement is the primary variable controlling the strength or levels of induced behavior. The operant response requirement within the schedule context has not been extensively studied as a determinant of ...
Lupfer-Johnson Gwen - - 2008
The author presented dwarf hamsters (Phodopus campbelli) and golden hamsters (Mesocricetus auratus) with conspecific and inanimate signals for food. Both species approached a cardboard stimulus that predicted food. The dwarf hamsters engaged in high levels of social contact directed toward a conspecific conditioned stimulus for food, but the golden hamsters ...
Farrar A M - - 2008
Organisms often make effort-related choices based upon assessments of motivational value and work requirements. Nucleus accumbens dopamine is a critical component of the brain circuitry regulating work output in reinforcement-seeking behavior. Rats with accumbens dopamine depletions reallocate their instrumental behavior away from food-reinforced tasks that have high response requirements, and ...
Cook Michelle E - - 2008
Previous research suggests that agricultural herbicides interfere with olfactory-mediated behavior, such as responses to alarm signals and the ability to locate food, in aquatic organisms. In crayfish, aggressive interactions are also mediated by chemical signals. These social signals are important in establishing dominance, which in turn has an impact on ...
Zombeck Jonathan A - - 2008
Neural circuits implicated in drug conditioning, craving and relapse overlap extensively with those involved in natural reward and reinforcement. To determine whether specificity could be detected in conditioned brain responses to drugs versus food, male outbred HSD:ICR mice were conditioned to a common environment using either 20 mg/kg cocaine (ip) ...
Epstein Leonard H LH Department of Pediatrics, School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, NY 14214-3000, USA. - - 2008
Pediatric obesity involves choices among healthy and less healthy alternatives, as well as choices whose consequences vary over time, such as engaging in unhealthy behaviors now at the expense of future health. The purpose of this study was to examine the relative reinforcing value of food and behavioral impulsivity under ...
Temple Jennifer L - - 2008
The reinforcing value of food is one factor that influences energy intake. The purpose of this study was to determine if the reinforcing value of highly liked snack foods could be modified by restriction or daily intake of individual preferred foods in the absence of changes in total energy intake. ...
Theopold Christoph - - 2007
BACKGROUND: Surgical repair of soft tissue trauma in the upper limb frequently requires postoperative immobilization to prevent tension across repaired tendons, vessels, or nerves. A plaster of Paris backslab, placed on either the volar or the dorsal surface, is frequently used, as it is inexpensive and easy to apply. METHODS: ...
Madden Gregory J - - 2007
This experiment was conducted to test the predictions of two behavioral-economic approaches to quantifying relative reinforcer efficacy. The normalized demand analysis suggests that characteristics of averaged normalized demand curves may be used to predict progressive-ratio breakpoints and peak responding. By contrast, the demand analysis holds that traditional measures of relative ...
Reed Miranda N - - 2008
It has recently been demonstrated that developmental exposure to methylmercury (MeHg) is associated with perseveration on operant tasks. An understanding of the behavioral mechanisms underlying this phenomenon may improve human testing of MeHg exposures and could provide insight into clinical syndromes that include perseveration as a component. One possible mechanism ...
Ghitza Udi E - - 2007
A major problem in treating obesity is high rates of relapse to maladaptive food-taking habits during dieting. This relapse is often provoked by acute re-exposure to palatable food, food-associated cues, or stress. We used a reinstatement model, commonly used to study relapse to abused drugs, to explore the effect of ...
Grasing Kenneth - - 2008
RATIONALE: Acetylcholine (ACh) is involved in brain reward and learning functions and contributes to opiate- and psychostimulant-motivated behaviors. Tacrine is a centrally acting, reversible cholinesterase inhibitor that also inhibits monoamine oxidase (MAO) and blocks reuptake of dopamine (DA) and serotonin. OBJECTIVES: To determine the effects of pretreatment with tacrine on ...
Jennings Dómhnall J - - 2007
In 3 experiments, the authors investigated the effect of stimulus duration on overshadowing. Experiments 1 and 2 examined responding to a target conditioned stimulus (CS1) when it was conditioned in compound with a coterminating overshadowing stimulus (CS2) that was longer, shorter, or of the same duration (the long, short, and ...
Epstein Leonard H - - 2007
The authors measured food reinforcement, polymorphisms of the dopamine D2 receptor (DRD2) and dopamine transporter (DAT1) genes, and laboratory energy intake in 29 obese and 45 nonobese humans 18-40 years old. Food reinforcement was greater in obese than in nonobese individuals, especially in obese individuals with the TaqI A1 allele. ...
Temple Jennifer L - - 2008
Within-session decreases in instrumental responding to obtain food, consistent with habituation, have been reliably demonstrated in adults and children. This study tested the hypothesis that within-session decreases in instrumental responding for food are due to habituation rather than satiation. Thirty-eight 8-12-year-old children performed a computer-based operant task to earn points ...
Fox Andrew T - - 2008
The spontaneously hypertensive rat (SHR) has been studied extensively as a purported rodent model of attention-deficit/hyperactivity disorder (ADHD). Because ADHD in humans is partially defined by marked impulsivity, SHRs, if a valid model of ADHD, ought to behave more impulsively than their normotensive parent strain, Wistar Kyoto (WKY). This prediction ...
Chilingaryan L I - - 2007
The same stimulus (a flash of light at a frequency of 6 Hz) was used in dogs to develop a food-related conditioned reflex reinforced by attractive food and an aversive conditioned reflex (avoidance/escape from paw stimulation) and differential inhibition to it (unavoidable series). This was followed by alternate experiments with ...
Epstein Leonard H - - 2007
Eating represents a choice among many alternative behaviors. The purpose of this review is to provide an overview of how food reinforcement and behavioral choice theory are related to eating and to show how this theoretical approach may help organize research on eating from molecular genetics through treatment and prevention ...
Machado Armando - - 2007
Two experiments examined how pigeons differentiate response patterns along the dimension of number. In Experiment 1, 5 pigeons received food after pecking the left key at least N times and then switching to the right key (Mechner's Fixed Consecutive Number schedule). Parameter N varied across conditions from 4 to 32. ...
Goldfield Gary S - - 2008
The present study examined the independent and interactive association between smoking, gender, dietary restraint and the relative reinforcing value of snack food in a university sample. Four hundred and three introductory psychology students completed questionnaires assessing age, gender, BMI, hunger, smoking status, nicotine dependence, dietary restraint, hedonic ratings and the ...
Garey Joan - - 2007
Acrylamide (ACR) is a neurotoxicant known to produce peripheral neuropathy in rats and humans, but little is known of its potential for producing cognitive or motivational alterations. Chronic exposure to low doses of ACR as a food contaminant is known to occur widely in humans. This research evaluated the effects ...
Naleid Amy M AM Department of Psychiatry & Behavioral Sciences, University of Washington, Seattle, WA 98108, - - 2008
Rats and humans avidly consume flavored foods that contain sucrose and fat, presumably due to their rewarding qualities. In this study, we hypothesized that the complex mixture of corn oil, sucrose, and flavor is more reinforcing than any of these components alone. We observed a concentration-dependent increase in reinforcers of ...
Escobar Rogelio - - 2007
The acquisition of lever pressing by rats and the occurrence of unreinforced presses at a location different from that of the reinforced response were studied using different delays of reinforcement. An experimental chamber containing seven identical adjoining levers was used. Only presses on the central (operative) lever produced food pellets. ...
Mazur James E - - 2007
Pigeons responded in a successive-encounters procedure that consisted of a search state, a choice state, and a handling state. The search state was either a fixed-interval or mixed-interval schedule presented on the center key of a three-key chamber. Upon completion of the search state, the choice state was presented, in ...
Zentall Thomas R - - 2007
When behavior suggests that the value of a reinforcer depends inversely on the value of the events that precede or follow it, the behavior has been described as a contrast effect. Three major forms of contrast have been studied: incentive contrast, in which a downward (or upward) shift in the ...
DeFulio Anthony - - 2007
Two experiments examined pigeons' postponement of a signaled extinction period, or timeout (TO), from an ongoing schedule of response-dependent food delivery. A concurrent-operant procedure was used in which responses on one (food) key produced food according to a variable-interval schedule and responses on a second (postponement) key delayed the next ...
Balani Kantesh - - 2007
Wear behavior of plasma-sprayed carbon nanotube (CNT)-reinforced hydroxyapatite (HA) coating is evaluated in the simulated body fluid environment. Apart from enhancing the fracture toughness and providing biocompatibility, CNT-reinforced HA coating demonstrated superior wear resistance compared with that of hydroxyapatite coating without CNT. Initiation and propagation of microcracks during abrasive wear ...
Filip MaƂgorzata - - 2007
In the present study we investigated the effects of the GABA(B) receptor antagonist (2S)-(+)-5,5-dimethyl-2-morpholineacetic acid (SCH 50911), the agonists baclofen and 3-aminopropyl(methyl)phosphinic acid (SKF 97541), and the allosteric positive modulator 3,5-bis(1,1-dimethylethyl)-4-hydroxy-beta,beta-dimethylbenzenepropanol (CGP 7930) on cocaine seeking behavior. The effects of the above drugs on the reinstatement of responding induced by ...
Porritt Matthew - - 2007
To examine whether CS-US pairing probability, hence rate (or probability) of food delivery, modulated the effects of cocaine, pigeons were exposed to an autoshaping procedure in which 6-s red, green, and white illuminations of a response key were immediately followed by response-independent food delivery with a probability of 1.0, 0.5, ...
Papaleo Francesco - - 2007
Altered motivational processes might participate to the physiopathology of eating-related disorders. The endogenous opioid system is thought to mediate the hedonic properties of food intake. To assess the role for the micro-opioid receptor (MOR) pathway in the motivational properties of food intake, in the present study we tested wild-type and ...
Soares Ernesto S - - 2007
The act of eating requires a decision by an animal to place food in its mouth. The reasons to eat are varied and include hunger as well as the food's expected reward value. Previous studies of tastant processing in the rat primary gustatory cortex (GC) have used either anesthetized or ...
Thalau Peter - - 2007
An experimental group of homing pigeons (Columba livia f. domestica) learned to associate food with a magnetic anomaly produced by bar magnets that were fixed to the bowl in which they received their daily food ration in their home loft; the control group lacked this experience. Both groups were trained ...
McLaughlin R J - - 2007
Reinstatement of previously extinguished instrumental responding for drug-related cues has been used as an animal model for relapse of drug abuse, and is disrupted by inactivation of the basolateral amygdala (BLA). However, the role that the BLA plays in reinstatement induced by cues associated with natural rewards is unclear. The ...
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