Search Results
Results 351 - 400 of 650
< 3 4 5 6 7 8 9 10 11 12 13 >
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 ...
Izquierdo Alicia A Section on the Neurobiology of Learning and Memory, Laboratory of Neuropsychology, National Institute of Mental Health, National Institutes of Health, Bethesda, Maryland 20892-4415, USA. - - 2004
The orbital prefrontal cortex (PFo) operates as part of a network involved in reward-based learning and goal-directed behavior. To test whether the PFo is necessary for guiding behavior based on the value of expected reward outcomes, we compared four rhesus monkeys with two-stage bilateral PFo removals and six unoperated controls ...
Sclafani Anthony A Department of Psychology, Brooklyn College, Brooklyn, NY 11210-2889, USA. - - 2004
The postingestive satiating action of food is often viewed as producing a positive affective state that rewards eating. However, in an early test of this idea, Van Vort and Smith [Physiol. Behav. 30 (1983) 279] reported that rats did not learn to prefer a food that was "real-fed" and satiating ...
Johansson Linda - - 2004
The role of sensitivity of external food cues in producing attentional bias toward food-, body-weight-, and shape-related words on the Stroop and the dot probe tasks was examined. Contrary to expectations, individuals high in responsiveness to external food cues directed attention away from food words, whereas individuals low in responsiveness ...
Araujo J A - - 2004
Assessment of canine palatability is important for both the pet food and pharmaceutical industries; however, the current palatability assessment protocols are limited in their utility. The most common technique, the two-pan test, does not control for the satiating effects of food and may not be useful for long-term palatability analysis ...
Ishibashi Hidetoshi - - 2004
Many animal species including humans are endowed with the ability to use biological cues and can extract information by observing other individuals. This study explored whether the macaque monkey could use biological cue to find a hidden target. When the experimenter hid food in one hand and crossed and uncrossed ...
Call Josep - - 2004
Bonobos (Pan paniscus; n = 4), chimpanzees (Pan troglodytes; n = 12), gorillas (Gorilla gorilla; n = 8), and orangutans (Pongo pygmaeus; n = 6) were presented with 2 cups (1 baited) and given visual or auditory information about their contents. Visual information consisted of letting subjects look inside the ...
Davies K L - - 2004
BACKGROUND AND AIMS: In 1987, Kjellsson and Rasmussen described the labellar trichomes of Dendrobium unicum Seidenf. and proposed that these hairs function as pseudopollen. Pseudopollen is a mealy material that superficially resembles pollen, is usually laden with food substances and is formed when labellar hairs either fragment into individual cells ...
Milgram Norton W - - 2004
The effects of long-term treatment with both antioxidants and a program of behavioral enrichment were studied as part of a longitudinal investigation of cognitive aging in beagle dogs. Baseline performance on a battery of cognitive tests was used to assign 48 aged dogs (9-12 years) into four cognitively equivalent groups, ...
Lerman Caryn C Department of Psychiatry, Abramson Cancer Center, University of Pennsylvania, 3535 Market Street, Suite 4100, Philadelphia, PA 19104, USA. - - 2004
Despite the high prevalence and public health significance of weight gain following smoking cessation, little is known about the underlying bio-behavioral mechanisms or effective therapies. We evaluated the effects of bupropion on food reward following smoking abstinence and the moderating influence of genotype. Seventy-one smokers of European ancestry were genotyped ...
Davis Caroline C Kinesiology and Health Sciences, 343 Bethune College, York University, 4700 Keele Street, Toronto, Ont., Canada M3J 1P3. - - 2004
Sensitivity to reward (STR)-a personality trait firmly rooted in the neurobiology of the mesolimbic dopamine system-has been strongly implicated in the risk for addiction. This construct describes the ability to derive pleasure or reward from natural reinforcers like food, and from pharmacologic rewards like addictive drugs. Recently experts in the ...
Calef Richard S RS West Virginia Wesleyan College, Buckhannon, WV 26201, USA. - - 2004
During preshift, one experimental group of rats was given a large magnitude of food reward following a traversal of a straight alley and during a goalbox placement, while the other experimental group was given a small reward during goalbox placement and a large reward following a run. During postshift, all ...
Cleveland Allison - - 2004
Tool use and transport represent cognitively important aspects of early hominid evolution, and nonhuman primates are often used as models to examine the cognitive, ecological, morphological and social correlates of these behaviors in order to gain insights into the behavior of our early human ancestors. In 2001, Jalles-Filho et al. ...
< 3 4 5 6 7 8 9 10 11 12 13 >