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Results 301 - 350 of 612
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Peciña Susana S Department of Psychology, University of Michigan, Ann Arbor, MI 48109, USA. - - 2006
Corticotropin-releasing factor (CRF) is typically considered to mediate aversive aspects of stress, fear and anxiety. However, CRF release in the brain is also elicited by natural rewards and incentive cues, raising the possibility that some CRF systems in the brain mediate an independent function of positive incentive motivation, such as ...
Roth Megan E - - 2005
Clinical and preclinical data suggest that fluctuations in ovarian steroid hormones across the menstrual/estrous cycle influence spontaneous feeding behavior in females. The effects of gender, menstrual cycle phase, and ovarian hormone fluctuations on food-maintained responding under a progressive-ratio schedule were investigated in four female and three male cynomolgus monkeys. Females ...
Aoki Naoya N Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya 464-8601, - - 2006
The effects of bilateral chemical lesions of the ventral striatum (nucleus accumbens and the surrounding areas in the medial striatum) and arcopallium (major descending area of the avian telencephalon) were examined in 1-2-weeks old domestic chicks. Using a Y-maze, we analyzed the lesion effects on the choices that subject chicks ...
Cagniard Barbara B Department of Neurobiology, Pharmacology and Physiology, The University of Chicago, Chicago, IL 60637, USA. - - 2006
Dopamine has been critically implicated in learning and motivation, although its precise role remains to be determined. In order to investigate the involvement of dopamine in learning and motivation for a food reward, we used dopamine transporter knockdown mice (DAT KD) that have chronically elevated levels of extracellular dopamine. The ...
Santos Laurie R - - 2005
The authors examined how 2 lemur species (Eulemur fulvus and Lemur catta) reason about tools. Experiment 1 allowed subjects to use 1 of 2 canes to retrieve an inaccessible food reward. Lemurs learned to solve this problem as quickly as other primates. Experiment 2 then presented subjects with novel tools ...
Hopkins William D - - 2005
Humans throw right-handed, and it has been suggested that the neurophysiological demands of aimed throwing may have served as a precursor to the evolution of left hemisphere specialization for linguistic functions. Although there are descriptions of throwing by wild and captive chimpanzees (Pan troglodytes), systematic observations of aimed throwing and ...
Silk Joan B JB Department of Anthropology, University of California, Los Angeles, California 90095, USA. - - 2005
Humans are an unusually prosocial species-we vote, give blood, recycle, give tithes and punish violators of social norms. Experimental evidence indicates that people willingly incur costs to help strangers in anonymous one-shot interactions, and that altruistic behaviour is motivated, at least in part, by empathy and concern for the welfare ...
Balleine Bernard W BW Department of Psychology and the Brain Research Institute, University of California, Box 951563, Los Angeles, CA 90095-1563, United States. - - 2005
Recent studies suggest that there are multiple 'reward' or 'reward-like' systems that control food seeking; evidence points to two distinct learning processes and four modulatory processes that contribute to the performance of food-related instrumental actions. The learning processes subserve the acquisition of goal-directed and habitual actions and involve the dorsomedial ...
Ohmura Yu Y Department of Behavioral Science, Hokkaido University, N10 W7 Kita-ku, Sapporo, 060-0810, Japan. - - 2005
Nicotine dependence has been associated with impulsivity and discounting delayed/uncertain outcomes. This study had two main objectives: (1) to examine the relationship between the number of cigarettes consumed per day and the degree to which delayed and uncertain monetary gains and losses are discounted by smokers, and (2) to determine ...
Franken Ingmar H A - - 2005
According to the theory of J.A. Gray, a strongly reactive approach system is highly sensitive to reward or to cues that signal reward. This implies that intake driven by the rewarding properties of food should be affected by individual differences in reactivity of the approach system. The present study examined ...
Paukner Annika - - 2006
This study investigated capuchin monkeys' understanding of their own visual search behavior as a means to gather information. Five monkeys were presented with three tubes that could be visually searched to determine the location of a bait. The bait's visibility was experimentally manipulated, and the monkeys' spontaneous visual searches before ...
Yonghui Li L Institute of Psychology, Chinese Academy of Sciences; Laboratory of Mental Health, Chinese Academy of Sciences, P.R. China. - - 2006
Behavioural studies have provided strong evidence for common substrates in the rewards of natural and addictive substances, but it is still unclear whether there is a common glutamatergic NMDA receptor mechanism involved in the processing of reward for both. The present study was designed to investigate the effects of MK-801 ...
Izawa Ei-Ichi E Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya 464-601, - - 2005
To identify the neuro-cognitive substrates of valuation and choice, we analysed the neural correlates of anticipated food rewards in the ventral striatum of freely behaving chicks. One-week-old chicks were trained in a color-discrimination task using four color cues (red, yellow, green and blue), each of which was associated with a ...
Herzig Volker V Neuropharmacology, Zoological Institute, Faculty of Biology, University of Tübingen, Germany. - - 2005
Recent studies have revealed the effectiveness of 2-methyl-6-(phenylethynyl)pyridine (MPEP), a highly selective antagonist of metabotropic glutamate receptors subtype 5 (mGluR5), in conditioned drug reward. In a previous study we showed that MPEP blocks expression of context-conditioned morphine- but not cocaine reward in the rat. The present study now examines the ...
O'Malley Robert C - - 2005
Interpopulation variability in patterns of food processing, similar to what is described as "traditional" or "cultural" variation in chimpanzees (Pan troglodytes) and orangutans (Pongo pygmaeus), was identified in white-faced capuchins (Cebus capucinus). However, recent comparisons of food processing in capuchins were conducted only at the population level, with relatively little ...
Bicca-Marques Júlio César JC Pontifícia Universidade Católica do Rio Grande do Sul, Brazil. - - 2005
Rainforest primates need to apply distinct foraging rules for efficiently using the spatial knowledge of the distribution of resources showing different temporal patterns of renewal. A win-stay rule is very important for exploiting abundant, long-lasting resources. Here, the author tests the use of this rule in wild groups of emperor ...
Padoa-Schioppa Camillo - - 2006
We studied economic choice behavior in capuchin monkeys by offering them to choose between two different foods available in variable amounts. When monkeys selected between familiar foods, their choice patterns were well-described in terms of relative value of the two foods. A leading view in economics and biology is that ...
Beran Michael J - - 2005
Two chimpanzees and a rhesus macaque rapidly learned the ordinal relations between 5 colors of containers (plastic eggs) when all containers of a given color contained a specific number of identical food items. All 3 animals also performed at high levels when comparing sets of containers with sets of visible ...
Stevens Jeffrey R JR Department of Psychology and Primate Cognitive Neuroscience Laboratory, Harvard University, Cambridge, MA 02138, USA. - - 2005
Decision making often involves choosing between small, short-term rewards and large, long-term rewards. All animals, humans included, discount future rewards--the present value of delayed rewards is viewed as less than the value of immediate rewards. Despite its ubiquity, there exists considerable but unexplained variation between species in their capacity to ...
Anapol F - - 2005
Body weight and length, chest girth, and seven postcranial limb segment lengths are compared between two guenon species, Chlorocebus (Cercopithecus) aethiops (vervets) and Cercopithecus mitis (blue monkeys), exhibiting different habitual locomotor preferences. The subjects, all adults, were wild caught for a non-related research project (Turner et al. [1986] Genetic and ...
Drapier Maud M Centre d'Ecologie, Physiologie et Ethologie, Centre National de la Recherche Scientifique, UPR 9010, Strasbourg, - - 2005
To assess how brown capuchin monkeys (Cebus apella) delay gratification and maximize payoff, we carried out four experiments in which six subjects could exchange food pieces with a human experimenter. The pieces differed either in quality or quantity. In qualitative exchanges, all subjects gave a piece of food to receive ...
Wellman Laurie L LL Interdisciplinary Program in Neuroscience and Department of Pharmacology, Georgetown University, Washington, DC 20007, - - 2005
Amygdala ablation disrupts reinforcer "devaluation" in monkeys (Malkova et al., 1997). Here, we tested the hypothesis that transient inactivation of amygdala by the GABA(A) agonist muscimol (MUS), specifically during the period of reward satiation, would have a similar effect. Six pigtail macaques were trained on a visual object discrimination task ...
Cummins-Sebree Sarah E - - 2005
Cotton-top tamarins (Saguinus oedipus) selected canes positioned so that a straight inward pull brought food within reach (M. D. Hauser, 1997; see also record 1997-41347-003). Tamarins failed to retrieve food with canes in other positions, and they did not reposition these canes. In this study, tufted capuchin monkeys (Cebus apella) ...
Wilson Fraser A W - - 2005
We describe a custom-built feeder based on stepping motor technology controlled by a laboratory computer. The feeder dispenses a wide range of foods: any fruit, vegetable, or nut. The feeder allows the investigator to reward monkeys with different foods within a single experimental day. The monkey's motivation to perform tasks ...
Hermer-Vazquez Linda L Department of Physiology and Pharmacology, SUNY Health Science Center, Brooklyn, NY 11203, USA. - - 2005
Two groups of rats, one rewarded with sweetened food and the other rewarded with medial forebrain bundle (MFB) stimulation, were trained to home in on and dig for a buried object coated with a target odor. After each group had 15 training trials, MFB rats searched with greater accuracy and ...
Brown Gillian R - - 2005
Infant marmosets and tamarins obtain solid food items from adults during and after the time of weaning. In addition to providing nutrients, food transfers may provide infants with the opportunity to learn about diet. The aim of this study was to investigate patterns of begging and food transfer in captive ...
Meyer Carl G - - 2005
We used behavioural conditioning to demonstrate that sharks can detect changes in the geomagnetic field. Captive sharks were conditioned by pairing activation of an artificial magnetic field with presentation of food over a target. Conditioned sharks subsequently converged on the target when the artificial magnetic field was activated but no ...
Gómez-Laplaza Luis M - - 2005
The ability of the cichlid angelfish, Pterophyllum scalare, to associate time and place to locate food, provided twice a day in two different places, was tested. Food was delivered daily in one corner of the tank in the morning and in the diagonally opposite corner in the afternoon, for a ...
Schaffner Colleen M - - 2005
Reconciliation is the post-conflict friendly reunion between opponents. A series of conditions and rules in order for reconciliation to take place has been recently proposed. One critical condition is that the relationship between opponents must be disrupted. We tested this condition using post-conflict and matched-control observations on 4 small groups ...
Dumont Eric C EC The Vollum Institute and Department of Behavioral Neuroscience, Oregon Health & Science University, Portland, Oregon 97239, - - 2005
Understanding the neurobiology of motivation might help in reducing compulsive behaviors such as drug addiction or eating disorders. This study shows that excitatory synaptic transmission was enhanced in the bed nucleus of the stria terminalis of rats that performed an operant task to obtain cocaine or palatable food. There was ...
Sharf Ruth - - 2005
We recently demonstrated that dopamine D1 receptors in the ventral tegmental area (VTA) are involved in intravenous cocaine reward. Here, we investigated whether VTA D1 receptors also are involved in food reward by testing the hypothesis that blockade of dopamine D1 receptors in the VTA attenuates the rewarding effects of ...
Kralik Jerald D - - 2005
When presented with a choice between 1 and 3 pieces of food in a type of reversed contingency task, 4 cotton-top tamarins (Saguinus oedipus) consistently chose the 3 pieces of food and received nothing, even though the choice of 1 piece would have yielded 3. However, in a task in ...
Salamone J D JD Division of Behavioral Neuroscience, Dept of Psychology, University of Connecticut, Storrs, Connecticut 06269-1020, USA. - - 2005
According to the dopamine (DA) hypothesis of reward, DA systems in the brain, particularly in the nucleus accumbens, are thought to directly mediate the rewarding or primary motivational characteristics of natural stimuli such as food, water and sex, as well as various drugs of abuse. However, there are numerous problems ...
Wang Szu-Han SH University of California, Los Angeles, USA. - - 2005
Incentive learning is the process via which animals update changes in the value of rewards. Current evidence suggests that, for food rewards in rats, this learning process involves the amygdala. However, it remains unclear whether this learning undergoes protein synthesis-dependent consolidation and "reconsolidation" processes in the lateral and basal nuclei ...
Santos Laurie R - - 2005
Most studies of animal tool use require subjects to use one object to gain access to a food reward. In many real world situations, however, animals perform more than one action in sequence to achieve their goals. Of theoretical interest is whether animals have the cognitive capacity to recognize the ...
Lewis Kerrie P - - 2005
A wealth of data demonstrating that monkeys and apes represent number have been interpreted as suggesting that sensitivity to number emerged early in primate evolution, if not before. Here we examine the numerical capacities of the mongoose lemur (Eulemur mongoz), a member of the prosimian suborder of primates that split ...
Behie Alison M - - 2005
The diet and activity of a population of Alouatta pigra were compared before and immediately after a major hurricane to begin to explore how the monkeys cope with severe habitat destruction. Focal animal data were collected from January to April (dry season) for two seasons before (368 h) and one ...
Schmidt Manfred - - 2005
In the spiny lobster Panulirus argus the antennules carrying olfactory sensilla called aesthetascs and several types of other non-olfactory sensilla accompanying them are frequently groomed by the third maxillipeds in a stereotyped behavioral pattern. This behavior can be elicited by chemical stimulation with l-glutamate. Using selective sensillar ablations, we tested ...
Mead Andy N AN Department of Psychology, School of Life Sciences, University of Sussex, BN1 9QG, UK. - - 2005
The conditioned place preference (CPP) paradigm has been used as a measure of the rewarding effects of a number of stimuli. Critically, this classical conditioning procedure requires the formation of associations between a rewarding stimulus and environmental cues, and the ability of these cues to direct subsequent behaviour. The purpose ...
Mattison Julie A - - 2005
Human studies have documented age-related declines in caloric intake that are pronounced at advanced ages. We examined caloric intake from a longitudinal study of aging in 60 male and 60 female rhesus monkeys (Macaca mulatta) collected for up to 10 years. Monkeys were provided a standardized, nutritionally fortified diet during ...
Moura A C de A - - 2004
Wild capuchin monkeys inhabiting dry forest were found to customarily use tools as part of their extractive foraging techniques. Tools consisted of twigs and sticks, often modified, which were used to probe for insects and, most frequently, of stones of a variety of sizes and shapes used for cracking and ...
Flombaum Jonathan I - - 2004
A manual-search experiment with rhesus monkeys (Macaca mulatta) explored dynamic object individuation in the tunnel effect: Subjects watched as a lemon rolled down a ramp and came to rest behind a tunnel (Occluder 1) and then as a kiwifruit emerged and became occluded at the end of its path behind ...
Fragaszy Dorothy - - 2004
We conducted an exploratory investigation in an area where nut-cracking by wild capuchin monkeys is common knowledge among local residents. In addition to observing male and female capuchin monkeys using stones to pound open nuts on stone "anvils," we surveyed the surrounding area and found physical evidence that monkeys cracked ...
Harris Heather G - - 2004
Stainless steel circular mirrors were employed in an enrichment plan for 105 singly housed male African green monkeys. We observed 25 randomly selected males to measure mirror use and to assess the mirrors' effectiveness as an enrichment item. We conducted additional mirror-use surveys on all 105 males using fingerprint accumulation ...
Bush Eliot C - - 2004
Extant anthropoids have large brains, small olfactory bulbs, and high-acuity vision compared with other primates. The relative timing of the evolution of these characteristics may have important implications for brain evolution. Here computed tomography is used to examine the cranium of a fossil anthropoid, Parapithecus grangeri. It is found that ...
McKenzie Tammy - - 2004
In seven experiments, 2 squirrel monkeys were given choices between arrays of food that varied in the quantity offered. In Experiments 1-5, the monkeys were offered choices between quantities of the same food that varied in a 2:1 ratio. The squirrel monkeys failed to show the temporal myopia effect or ...
Horner Amy J - - 2004
Benthic crustaceans rely on chemical stimuli to mediate a diversity of behaviors ranging from food localization and predator avoidance to den selection, conspecific interactions and grooming. To accomplish these tasks, Caribbean spiny lobsters (Panulirus argus) rely on a complex chemosensory system that is organized into two parallel chemosensory pathways originating ...
Parker Karen J - - 2004
BACKGROUND: Retrospective studies in humans have identified characteristics that promote stress resistance, including childhood exposure to moderately stressful events (ie, stress inoculation). OBJECTIVE: Because of limited opportunities for prospective studies in children, we tested whether exposure to moderate stress early in life produces later stress resistance in a primate model. ...
Huang Xun-Bin - - 2004
AIM: To examine the effect of sildenafil citrate on penile erection of male rhesus macaque. METHODS: Twenty Macaca mulatta were divided into the sildenafil treated and the control groups of 10 animals each. The penile size, the corpus cavernosal electromyogram (EMG) and the intra-corpus cavernosal pressure (ICP) were determined. RESULTS: ...
Spinozzi Giovanna - - 2004
This study investigates prehension in 20 tufted capuchins (Cebus apella) in a reaching task requiring individuals to grasp a small food item fixed to a tray. The aim was twofold: 1) to describe capuchins' grasping techniques in detail, focusing on digit movements and on different areas of contact between the ...
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