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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. ...
Henrich Joseph J Department of Anthropology, Emory University, Atlanta, Georgia 30322, USA. - - 2004
Brosnan and de Waal have shown that capuchin monkeys are more likely to reject a cucumber slice after seeing that another capuchin has received a more attractive grape. In interpreting this finding, the authors make a link to work in humans on 'inequity aversion' and suggest that capuchins, like humans, ...
Stevens Jeffrey R - - 2004
Animals may share food to gain immediate or delayed fitness benefits. Previous studies of sharing have concentrated on delayed benefits such as reciprocity, trade and punishment. This study tests an alternative model (the harassment or sharing-under-pressure hypothesis) in which a food owner immediately benefits because sharing avoids costly harassment from ...
Bicca-Marques Júlio César - - 2004
Early in their evolution, the ancestors of anthropoid primates radiated from a nocturnal to a diurnal niche. Foraging during the night differs from foraging during the day in terms of the availability of light and color cues, and in the movement of odor molecules through the canopy. In this study, ...
Garber P A - - 2004
From September through November 2000 we conducted an experimental field study of tool use in a group of 15 wild white-faced capuchins (Cebus capucinus) in Costa Rica. The problem presented to the capuchins involved the use of wooden dowels as probes to obtain a food reward (two bananas) located inside ...
Enstam Karin L - - 2004
Habitat structure can be important in determining habitat preference of animals because it is often closely linked to factors that affect survival and reproduction, such as food availability and predation risk. Here we examine the ways in which microhabitat structure and predation risk affect the habitat preference of wild patas ...
Lisboa Cristiane Varella - - 2004
A breeding in captivity program of neotropical primates for subsequent reintroduction in nature is in progress at the Primatology Center of Rio de Janeiro (CPRJ). Almost 200 animals of 20 species that include both wild captured animals and specimens born in captivity are maintained in CPRJ. Here, we examined 198 ...
Leavens David A - - 2004
Two experiments were conducted to assess the referential function of chimpanzee (Pan troglodytes) gestures to obtain food. The chimpanzees received 1 trial per condition. In Experiment 1 (N = 101), in full view of the chimpanzee, a banana was placed on top of 1 of 2 inverted buckets or was ...
Anderson James R JR Department of Psychology, University of Stirling, Stirling, Scotland. - - 2004
Squirrel monkeys (Saimiri sciureus) that had learned to reach toward 1 piece of food instead of 4 in a reverse-reward contingency were tested after an 8-month delay with no intervening relevant experiences. All monkeys except 1 continued to show inhibitory control by reliably reaching toward the smaller quantity, most of ...
Hopkins William D - - 2004
Asymmetries in motor skill when grasping small food items was evaluated in a sample of captive chimpanzees. In two experiments, error rates in grasping food were assessed when controlling for individual differences in grip morphology. In both experiments, chimpanzees were found to make more errors with the left compared to ...
Hampton Robert R - - 2004
The hippocampus is critical for remembering locations in a wide variety of species, including humans. However, recent findings from monkeys following selective hippocampal lesions have been equivocal. To approximate more closely the situations in which rodents and birds are tested, we used a spatial memory task in which rhesus monkeys ...
Jones Clara B - - 2004
This study surveyed 33 male hunters between the ages of 17 and 54 at the Community Baboon Sanctuary (CBS), Belize, to evaluate attitudes and behaviors in relation to hunting black howler monkeys (Alouatta pigra). The study defined hunting restraint as a learned predisposition not to hunt 1 or more species ...
Addessi Elsa - - 2004
Despite more than 40 million years of independent evolution, capuchin monkeys and human children share several features that make a comparison in the domain of feeding behaviour interesting. As with humans, capuchin monkeys have a long life span and an extended infancy period; moreover, they are omnivorous and food neophobic. ...
Green Leonard L Department of Psychology, Washington University, Campus Box 1125, St. Louis, Missouri 63130, USA. - - 2004
Temporal discounting refers to the decrease in the present, subjective value of a reward as the time to its receipt increases. Results from humans have shown that a hyperbola-like function describes the form of the discounting function when choices involve hypothetical monetary rewards. In addition, magnitude effects have been reported ...
Pessiglione Mathias M Neurologie et Thérapeutique expérimentale (INSERM U289), Hôpital de la Salpêtrière, Paris, - - 2004
The motor and cognitive symptoms of Parkinson's disease (PD) are well documented, but little is known about the functionality of motivational processes mediated by the limbic circuits of basal ganglia. The aim of this study was to test the ability of motivational processes to direct and to urge behaviour, in ...
Mottley Kieron - - 2003
Juvenile budgerigars (Melopsittacus undulatus) observed thin film transistor video playback of a virtual conspecific demonstrator using its beak to remove a stopper from a food box, either by pulling the object upward or by pushing it downward. Simultaneously (Experiment 1) or subsequently (Experiment 2), the observers were offered a similar ...
Cleveland A - - 2003
Cannell [Journal of Archaeological Science 29:335-339, 2002] argued that sex-based differences among humans in terms of the mass of chosen throwing stones could be used to infer body mass and patterns of sexual dimorphism in early hominids from Olduvai and Koobi Fora by examining the mass distributions of unaltered stone ...
Egashira Toru - - 2003
The contaminants in deionized and distilled water (DDI water) boiled with polystyrene resin inhibited A-type monoamine oxidase (MAO, MAO-A preferentially deaminates serotonin and norepinephrine and regulates these amines concentration) activity in monkey brain mitochondria. To identify these contaminants, we attempted measurements by HPLC, FT-IR and NMR. The compound inhibiting MAO-A ...
Hauser Marc D - - 2003
Altruistic food giving among genetically unrelated individuals is rare in nature. The few examples that exist suggest that when animals give food to unrelated others, they may do so on the basis of mutualistic or reciprocally altruistic relationships. We present the results of four experiments designed to tease apart the ...
Mitchell Suzanne H. - - 2003
It has been suggested that when the delivery of several rewards is separated in time, e.g. one reward immediately and a second reward a few moments later, the value of an alternative that includes these "bundled" rewards will be the sum of the hyperbolic discount functions of the individual rewards. ...
Bugnyar Thomas - - 2004
Active misleading of conspecifics has been described as a social strategy mainly for primates. Here we report a raven leading a competitor away from food in a social foraging task. Four individuals had to search and compete for hidden food at color-marked clusters of artificial food caches. At the beginning ...
Call Josep - - 2003
This study investigated the ability of three chimpanzees and three orangutans to track the position of a reward after a series of displacements. The reward was placed under one of two opaque containers resting on a platform. Experiment 1 investigated rotational displacements in which the platform was rotated 0 degrees, ...
Westergaard Gregory C - - 2004
This research examined exchange and value attribution in tufted capuchin monkeys ( Cebus apella). We presented subjects with opportunities to obtain various foods and a tool from an experimenter in exchange for the foods or tool in the subjects' possession. The times elapsed before the first chow biscuits were expelled ...
Gilberto David B - - 2003
Models of chronic cerebrospinal fluid (CSF) collection previously have been established for nonhuman primates and canines; many of these methods implement stainless-steel cannulas into the lateral or 4th ventricles or catheters into the cerebral or spinal subarachnoid space. These models have proved successful and reliable but unfortunately require invasive techniques ...
Fujita Kazuo - - 2003
Four tufted capuchin monkeys (Cebus apella) were trained to choose from 2 hook-like tools, 1 of which successfully led to collecting food, whereas the other did not because of inappropriate spatial arrangement of the tool and the food. In Experiment 1, all of the monkeys successfully learned the basic task. ...
Vick Sarah-Jane - - 2003
The ability of 4 olive baboons (Papio anubis) to use human gaze cues during a competitive food task was investigated. Three baboons used head orientation as a cue, and 1 individual also used eye direction alone. As the baboons did not receive prior training with gestural cues, their performance suggests ...
Snowdon Charles T - - 2003
Many monkeys show social facilitation in sampling novel, palatable foods but not in avoiding unpalatable foods. Cotton-top tamarins (Saguinus oedipus) socially learned to avoid a preferred food when it was made unpalatable but showed no aversion toward a food not made unpalatable. Only 33% sampled unpalatable tuna, and few sampled ...
Weldon Paul J - - 2003
Neotropical monkeys of the genus Cebus anoint themselves by rubbing arthropods and plants against their pelage. A recent study has shown that free-ranging wedge-capped capuchin monkeys (C. olivaceus) in Venezuela self-anoint with a benzoquinone-secreting millipede, an activity by which they are hypothesized to appropriate chemical deterrents of mosquitoes. To evaluate ...
Kondo Hiromu - - 2003
We investigated the gastrointestinal transit of liquids, as well as various gastric pH profiles, in fed cynomolgus monkeys. Twelve grams of a biscuit-type solid food were provided 1 h before the test. The acetaminophen method was used to determine the gastric half-emptying time (t(50%)), which provided an estimate of the ...
de Kort Selvino R - - 2003
Food sharing among unrelated same-sex individuals has received considerable interest from primatologists and evolutionary biologists because of its apparent altruistic nature and implications for the evolution of complex social cognition. In contrast to primates, food sharing in birds has received relatively little attention. Here we describe three types of food ...
Bos Ruud van den - - 2003
In rats (Rattus norvegicus) anticipation to an oncoming food reward in an appetitive Pavlovian conditioning procedure is expressed as an increase of behavioural transitions, i.e. hyperactivity. This behaviour might be related to the spontaneous appetitive behaviour of animals in relation to oncoming food rewards. To deepen our insight into anticipatory ...
Hihara Sayaka - - 2003
Vocal production and its usage in nonhuman primates may share common features with primitive human language. We trained two Japanese monkeys to use a rake-shaped tool to retrieve distant food. After the training, the monkeys spontaneously began vocalizing coo-calls in the tool-using context. We then trained one of the monkeys ...
Harris Glenda C GC Department of Psychiatry, University of Pennsylvania, 705 Stellar Chance/6100, Philadelphia, PA 19104, - - 2003
Opiate abuse has been associated with cognitive deficits in human addicts. To determine if prior opiate exposure alters the ability to learn, we trained animals in an instrumental learning task for a food reward. During a 2-week period after withdrawal, morphine-abstinent rats were significantly slower at learning an escalating fixed-ratio ...
Green Leonard - - 2003
Rats were given a choice between a smaller, immediately available reward and a larger reward available after a delay. In one phase, the reward was food and in another phase, the reward was water. Constant delays were added between the choice presentation and the delivery of the reward alternatives. As ...
Ducoing A M - - 2003
The ability of Tonkean macaques (Macaca tonkeana) to deceive partner about the location of hidden food was investigated in 4 males belonging to a group raised in a 2-acre park. Before releasing subjects in the search task, the experimenter prompted 1 of the subjects to observe where the bait was ...
Izawa Ei-Ichi E Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya 464-8601, - - 2003
Effects of bilateral chemical lesions of the medial basal ganglia [lobus parolfactorius (LPO)] were examined in 7- to 14-d-old domestic chicks. Chicks were trained in a color discrimination task, in which the subject had to peck one of the two colored beads associated with rewards that differed in quantity (amount ...
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