Search Results
Results 201 - 250 of 1343
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Weatherly Jeffrey N - - 2007
Researchers have demonstrated that rats' rates of operant responding that are maintained by 1% liquid-sucrose reinforcement will increase if food-pellet reinforcement is upcoming within the same session. The authors investigated whether a similar induction effect would be observed when rats pressed a lever for 1% sucrose that was delivered by ...
Gulley Joshua M - - 2007
A goal of the current study was to determine if individual differences in cocaine-induced locomotion, which has been shown in outbred Sprague-Dawley (SD) rats to be correlated with differential function of dopamine transporters, were also evident in Long-Evans (LE) rats. Another objective was to determine if differences in locomotion following ...
Odum Amy L - - 2007
Although the effects of dopamine agonists on temporal discrimination have been widely studied, conclusions as to their behavioral and neurophysiological effects are difficult due to a number of discrepant findings in the literature. This study examined whether a previously unexplored procedural difference could account for some of these discrepancies. In ...
Doughty Adam H - - 2007
Resurgence refers to the transient recovery of previously reinforced, but presently not reinforced, responding when more recently reinforced responding is extinguished. The primary purpose of our research was to determine how differential resurgence results from the procedures used to eliminate that responding. There were three conditions in each of five ...
Aparicio Carlos F - - 2007
The idea that dopamine mediates the reinforcing effects of stimuli persists in the field of neurosciences. The present study shows that haloperidol, a dopamine antagonist, does not eliminate the reinforcing value of food reinforcers. The ratio of reinforcers changed seven times across two levers within sessions, modeling a dynamic environment. ...
Madden Gregory J - - 2007
This experiment was conducted to test predictions of two behavioral-economic approaches to quantifying relative reinforcer efficacy. According to the first of these approaches, characteristics of averaged normalized demand curves may be used to predict progressive-ratio breakpoints and peak responding. The second approach, the demand analysis, rejects the concept of reinforcer ...
Davison Michael - - 2007
Five pigeons were trained on a procedure in which seven concurrent variable-interval schedules arranged seven different food-rate ratios in random sequence in each session. Each of these components lasted for 10 response-produced food deliveries, and components were separated by 10-s blackouts. We varied delays to food (signaled by blackout) between ...
Pinkston Jonathan W - - 2007
Previous research has shown that patterns in operant responding may change within the course of individual experimental sessions. The proper interpretation of such changes is controversial. At least one source of this controversy may lie in unstated experimental practices across laboratories, as published reports often have failed to detail important ...
Ford Matthew M - - 2007
Although systemic allopregnanolone (ALLO; a positive modulator of GABA(A) receptors) has been shown to enhance ethanol-reinforced responding and to modulate drinking patterns in rodents, the effects of centrally administered ALLO on ethanol intake are not known. The current work examined the effects of intracranial ALLO on operant ethanol self-administration in ...
Banks Matthew L - - 2007
Although reinstatement of extinguished cocaine self-administration is widely used as an animal model of relapse, it is unclear which behavioral effects of the drug stimulus (i.e., unconditioned, discriminative or reinforcing) mediate the increases in responding after extinction. To examine the influence of experience with cocaine as a reinforcer on the ...
Macinnis Mika L M - - 2007
The goal was to determine whether rats time filled and empty intervals of equal duration differently. Each of five rats was trained for 50 sessions on an instrumental appetitive head entry procedure in which food was available (primed) every 120 s. On "empty" cycles, 30s prior to the next food ...
Mazur James E - - 2007
An adjusting-delay procedure was used to study rats' choices with probabilistic and delayed reinforcers, and to compare them with previous results from pigeons. A left lever press led to a 5-s delay signaled by a light and a tone, followed by a food pellet on 50% of the trials. A ...
Galarce Ezequiel M - - 2007
We examined the reinforcer-specificity of Pavlovian conditioning in the control of appetitive and consummatory behaviors in Pavlovian-to-instrumental transfer, cue-potentiated eating, and devaluation procedures. Rats received pairings of one conditioned stimulus with sucrose and another conditioned stimulus with maltodextrin. In Experiment 1, rats were also trained to earn sucrose for one ...
Ward Ryan D - - 2007
The present experiment examined the effects of several disruptors on temporal discrimination. Pigeons responded under a 0-delay symbolic matching-to-sample procedure in which responses to one key color were reinforced following the presentation of four shorter sample durations, and responses to another key color were reinforced following the presentation of four ...
Delparte J J - - 2007
Theta-burst magnetic fields (1 microT) designed to mimic electrical stimuli employed in vitro to affect long-term potentiation have been previously shown to impair the acquisition of conditioned fear. In the current study, the authors were interested in investigating whether similar magnetic fields could affect the consolidation of food-induced conditioned place ...
Evenden John - - 2007
Many similarities exist between the overconsumption of food, which results in obesity, and drug addiction. The present study investigated the effects of anorectic drugs on responding maintained by high incentive, but nutritionally unnecessary, food reinforcers using an FI15(fixed-ratio 10:S) schedule of reinforcement, similar to that used in studies on the ...
Ford Matthew M - - 2007
Ethanol reinforcement should ideally be evaluated in animals that are not food deprived to ensure that the motivation behind its consumption is pharmacological, and not caloric, in nature. The objective of this work was to assess the influence of reinforcement schedule on ethanol intake in nondeprived mice. Male C57BL/6J mice ...
Salamone J D JD Division of Behavioral Neuroscience, Department of Psychology, University of Connecticut, Storrs, CT, 06269-1020, USA. - - 2007
Over the last several years, it has become apparent that there are critical problems with the hypothesis that brain dopamine (DA) systems, particularly in the nucleus accumbens, directly mediate the rewarding or primary motivational characteristics of natural stimuli such as food. Hypotheses related to DA function are undergoing a substantial ...
Brozoski Thomas J - - 2007
Animal models have facilitated basic neuroscience research investigating the pathophysiology of tinnitus. It has been hypothesized that partial deafferentation produces a loss of tonic inhibition in the auditory system that may lead to inappropriate neuroplastic changes eventually expressed as tinnitus. The pathological down-regulation of gamma-amino butyric acid (GABA) provides a ...
Solís-Correa R E - - 2007
For short-term cardiovascular application, segmented polyurethanes (SPUs) based on 4,4-methylenebis(cyclohexyl isocyanate) (HMDI), polytetramethylenglycol (PTMG) and 1,4-butanediol (BD) were synthesized and characterized by spectroscopy (FT-IR, (1)H-NMR) and thermal (TGA, DMA, DSC) and mechanical techniques. The segmented nature of the SPUs was not easily established by spectroscopic means; however, TGA allowed the ...
Kodak Tiffany - - 2007
Factors that influence reinforcer choice have been examined in a number of applied studies (e.g., Neef, Mace, Shea, & Shade, 1992; Shore, Iwata, DeLeon, Kahng, & Smith, 1997; Tustin, 1994). However, no applied studies have evaluated the effects of postsession reinforcement on choice between concurrently available reinforcers, even though basic ...
Kodak Tiffany - - 2007
Factors that influence choice between qualitatively different reinforcers (e.g., a food item or a break from work) are important to consider when arranging treatments for problem behavior. Previous findings indicate that children who engage in problem behavior maintained by escape from demands may choose a food item over the functional ...
Ishii Taku T Centre for Integrated Research on the Mind, Keio University, 3-1-7 Mita-Toho Bldg. 7F, Mita, Minato-ku, Tokyo 108-8345, Japan. - - 2007
The present experiment examined overall and local effects of omission of reinforcers in a choice situation. Pigeons' key-pecking responses were reinforced under concurrent fixed-interval and random-interval schedules of food presentation. After some weeks of baseline sessions in which the probability of reinforcement was 1.00, approximately 25% of food presentations from ...
Ottani Alessandra A Department of Biomedical Sciences, Section of Pharmacology, University of Modena and Reggio Emilia, 41100 Modena, - - 2007
Palatability and variety of foods are major reasons for "hedonic" eating, and hence for overeating and obesity. Palatable food and drugs of abuse share a common reward mechanism, and compounds that block the reinforcing effect of drugs of abuse preferentially suppress the intake of palatable foods. This research was aimed ...
Weldon Douglas A DA Department of Psychology, Hamilton College, Clinton, NY 13323, United States. - - 2007
The activity of single units in the intermediate and deep layers of the superior colliculus was recorded while rats performed an operant conditioning task. On all trials, each animal pressed a bar and then inserted his snout into a food cup; on half of the trials, food reinforcement was available. ...
Riggio Lucia - - 2006
Inhibition of return (IOR) is a response delay that occurs when the target is preceded by an irrelevant stimulus (cue) at the same location. IOR can be object based, as well as location based. The aim of the present study was to investigate the role of the pragmatic features of ...
Semenova Svetlana - - 2007
Schizophrenia is characterized by attentional deficits possibly associated with glutamate dysfunction. The role of postsynaptic metabotropic glutamate 5 receptors (mGluR5) or presynaptic inhibitory mGluR2/3 on attention is currently unknown. We investigated the effects of the mGluR5 antagonist MPEP (2-methyl-6[phenylethynyl]-pyridine) and the mGluR2/3 antagonist LY341495 on attention in the 5-choice serial ...
Davison Michael - - 2006
Six pigeons were trained on a procedure in which seven components arranged different food-delivery ratios on concurrent variable-interval schedules each session. The components were unsignaled, lasted for 10 food deliveries, and occurred in random order with a 60-s blackout between components. The schedules were arranged using a switching-key procedure in ...
Roberts Nicole A - - 2006
This study examined whether individuals from 4 major ethnic groups within the United States (African American, Chinese American, European American, and Mexican American) showed greater subjective, behavioral, and physiological responses to emotional film clips (amusement, sadness, and disgust) with actors from their own ethnic group (ethnically matched) compared with actors ...
Ginsburg Brett C - - 2006
In previous studies, the selective serotonin reuptake inhibitor fluvoxamine preferentially reduced responding for ethanol compared with responding for food under conditions in which each was available alone in separate groups or in the same subjects under a multiple schedule in which baseline response rates were matched. The impact of providing ...
Udalova G P GP St. Petersburg Research Institute Center of Ecological Safety, Russian Academy of Sciences, - - 2006
The characteristics of learning in ants - active Myrmica rubra foragers - were studied in a maze at different levels of colony carbohydrate food need with reinforcement consisting of carbohydrate (sugar syrup) or protein (pupae of Lasius niger ants). Measures of the maze skill during learning reinforced with syrup were ...
Grant Douglas S - - 2007
Pigeons were trained to match 2- and 8-s food samples. The delay on training trials was either 0s (group 0sF), 5s (group 5sF), or varied between 2 and 8s (M=5s, group 5sV). Testing at a delay that exceeded the training delay by 15s in each group revealed a robust choose-short ...
Negus S S - - 2007
Monoamine releasers constitute one class of drugs under investigation as candidate medications for the treatment of cocaine abuse. Promising preclinical and clinical results have been obtained with amphetamine, which has high selectivity for releasing dopamine/norepinephrine versus serotonin. However, use of amphetamine as a pharmacotherapy is complicated by its high abuse ...
Crystal Jonathon D - - 2007
A defining feature of a circadian oscillator is that periodic output from the oscillator continues after the termination of periodic input. In contrast, a defining feature of a pacemaker-accumulator system is that elapsed time is measured with respect to the presentation of a stimulus, according to the classic description of ...
O'Dell Laura E - - 2007
The present study characterized nicotine intake, circadian patterns of food and water intake, precipitated somatic signs of withdrawal, and extinction of nicotine-seeking behavior in rats with 23-h access to intravenous self-administration (IVSA). Separate groups of animals were allowed access to nicotine IVSA (0.015, n = 9; 0.03, n = 14; ...
Colwill Ruth M - - 2007
The depressive effects of noncontingent and explicitly unpaired food unconditioned stimuli (USs) and the recovery from those effects on autoshaped responding were examined in a series of experiments with pigeons. In Experiments 1 and 2, responding to a keylight conditioned stimulus (CS) previously paired with food was depressed equally by ...
Ahn Soyon S Department of Psychiatry, University of British Columbia, 2255 Wesbrook Mall, Vancouver, British Columbia, V6T 2A1, - - 2007
Dopamine (DA) activity in the nucleus accumbens (NAc) is related to the general motivational effects of rewarding stimuli. Dickinson and colleagues have shown that initial acquisition of instrumental responding reflects action-outcome relationships based on instrumental incentive learning, which establishes the value of an outcome. Given that the sensitivity of responding ...
Odum Amy L - - 2006
Four experiments examined the effects of delays to reinforcement on key peck sequences of pigeons maintained under multiple schedules of contingencies that produced variable or repetitive behavior. In Experiments 1, 2, and 4, in the repeat component only the sequence right-right-left-left earned food, and in the vary component four-response sequences ...
Dallery Jesse - - 2007
Although voucher reinforcement has been shown to promote abstinence from smoking, more practical methods are needed to obtain objective evidence of smoking status on a frequent and sustained basis. Using a within-subject reversal design, the present study tested an Internet-based method to obtain objective evidence of smoking status and to ...
Raiff Bethany R - - 2006
There is growing recognition that nonnicotine factors, such as the sensory stimuli associated with smoking, can play a critical role in the maintenance of cigarette smoking. However, little is known about the effects of nicotine on responding maintained by these stimuli, which are assumed to be conditioned reinforcers. The authors ...
García Andrés - - 2006
In Experiment 1, 10 pigeons were exposed to a successive symbolic matching-to-sample procedure in which the sample was generated by the pigeons' own behavior. Each trial began with both response keys illuminated white, one being the "correct" key and the other the "incorrect" key. The pigeons had no way of ...
Nair S G - - 2006
We have recently adapted a reinstatement model, commonly used to study relapse to drugs of abuse, to study the role of stress and anxiety in relapse to palatable food seeking [Ghitza UE, Gray SM, Epstein DH, Rice KC, Shaham Y. The anxiogenic drug yohimbine reinstates palatable food seeking in a ...
Reutershan Jörg - - 2006
Alveolar recruitment is one of the beneficial effects of prone positioning in patients with ARDS (acute respiratory distress syndrome). However, responses vary among patients and, therefore, we hypothesized that alveolar recruitment is an individual time-dependent process and its measurement might be helpful to 'dose' prone positioning individually. In 13 patients ...
Ginsburg Brett C - - 2006
The cannabinoid CB1 antagonist rimonabant (SR141716A) has been proposed as a therapeutic agent for several addictive disorders, including alcoholism. Rimonabant may selectively reduce responding for an ethanol solution compared with an alternative. While this could represent a specific effect of CB1 inhibition on ethanol reinforcement, this could also result from ...
Podlesnik Christopher A - - 2006
Previous experiments have shown that unsignaled delayed reinforcement decreases response rates and resistance to change. However, the effects of different delays to reinforcement on underlying response structure have not been investigated in conjunction with tests of resistance to change. In the present experiment, pigeons responded on a three-component multiple variable-interval ...
Peters Jamie - - 2006
RATIONALE: Group II metabotropic glutamate receptor (mGluR2/3) agonists are proposed to serve as potential treatment for addiction. OBJECTIVES: The present study examined the hypothesis that mGluR2/3 agonists exert inhibitory effects on cocaine-induced reinstatement of cocaine-seeking. METHODS: Rats were trained to self-administer either cocaine or control reinforcer (food), then responding on ...
Temple Jennifer L - - 2006
Salivary responses habituate to repeated presentations of food cues, and these responses recover when new food stimuli are presented. Research suggests that within-session changes in motivated responding for food may also habituate, and motivated responding may, therefore, recover when new foods are presented. The purpose of this study was to ...
Buser Pierre - - 2006
This paper analyses an interesting story, that of the physiologist Ivan Petrovitch Pavlov. While investigating the causes of salivary secretions in the waking, behaving dog, he discovered a class of causes that he called psychic, since they were associated with perceiving a visual, acoustic or other signal, delivered before food ...
Ginsburg Brett C - - 2006
Acute treatment with fluvoxamine reduces responding for ethanol more than responding for food. However, pharmacotherapy for alcoholism is likely to require chronic treatment. These experiments were performed to assess the effects of chronic fluvoxamine on ethanol- and food-maintained behaviors. Effects of chronic fluvoxamine (10 and 17.8 mg/kg/dayx30 days) on ethanol- ...
Macdonall James S - - 2006
In a concurrent schedule, responding at each alternative is controlled by a pair of schedules that arrange reinforcers for staying at that alternative and reinforcers for switching to the other alternative. Each pair of schedules operates only while at the associated alternative. When only one pair of stay and switch ...
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