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Results 451 - 500 of 599
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Masterson T J - - 1997
Ontogenetic patterns of sexual dimorphism and cranial form in two capuchin monkeys, Cebus albifrons and C. apella, are investigated by means of univariate, bivariate, and multivariate statistics. The analyses are based on 23 linear variables. Univariate analyses indicate that similar ontogenetic patterns of cranial sexual dimorphism are present; however, interspecific ...
de Waal F B - - 1997
Capuchin monkeys (Cebus apella) share food even if their partner is behind a mesh restraint. Pairs of adult capuchins were moved into a test chamber in which 1 monkey received cucumber pieces for 20 min and the other received apple slices during the following 20 min. Tolerant transfers of food ...
DeCoteau W E WE Department of Psychology, University of Utah, Salt Lake City 84112, - - 1997
Memory for magnitude of reinforcement was assessed in rats using a go/no-go short-term memory paradigm. During the task's study phase rats were given a piece of cereal comprised of either 25 or 50% sugar. For all trials, one of the cereal types was designated positive, the other negative. On the ...
Schedin U - - 1997
BACKGROUND: High amounts of endogenous nitric oxide (NO) have been demonstrated in the human upper airway, but the role of nasal NO is still unclear. The present study aims to describe nasal NO excretion in different animal species with special living conditions or anatomy. METHODS: Domestic animals (horse, cow, pig, ...
Salinas J A JA Department of Psychology, University of Virginia, Charlottesville 22903, USA. - - 1997
These experiments examined the effects of posttraining intraamygdala administration of the muscarinic agonist, oxotremorine, and the beta-noradrenergic antagonist, propranolol, on memory for reduction in reward magnitude. Male Sprague-Dawley rats (175-200 g) implanted with bilateral intraamygdala cannulae were food deprived (maintained at 80% of body weight) and trained to run a ...
Bolen R H - - 1997
The authors tested free-ranging New World monkeys (nocturnal owl monkeys [Aotus nancymai] and diurnal capuchin monkeys [Cebus apella]) to determine the extent to which they use olfactory cues to locate food hidden in containers at 2 of 6 feeding sites within a 1 1/2-ha forested enclosure. These 2 sites were ...
Snowdon C T - - 1997
Affiliative behavior is often expressed through communication, and the nature of affiliative interactions affects the ontogeny of communication. I presented three phenomena that demonstrate the importance of affiliation in vocal development in marmosets and tamarins, but the results have parallels in many other species including birds, dolphins, and humans. Pygmy ...
Westergaard G C - - 1997
This research investigated the effects of posture on lateral bias for food reaching in tufted capuchin monkeys ( Cebus apella ) by comparing hand preferences for quadrupedal and bipedal reaching. Several findings of this investigation warrant discussion. First, we found a population-level bias towards use of the right hand for ...
Garber P A - - 1997
Despite a large body of data on diet and ranging patterns in prosimians, monkeys and apes, little is known regarding the types of information that non-human primates use when making foraging decisions. In a series of controlled field experiments, we tested the ability of wild capuchins (Cebus capucinus) at La ...
Westergaard G C - - 1997
This research examined tool and food transfer between two groups of tufted capcuhin monkeys (Cebus apella). Subjects in one group transferred stones to subjects in a second group who in turn used the stones as cutting tools and then transferred food to subjects in the first group. Aspects of the ...
Westergaard G C - - 1996
This research examined hand preference for a bimanual task in 45 tufted capuchin (Cebus apella) and 55 rhesus macaque (Macaca mulatta) monkeys. Investigators presented subjects with plastic tubes lined with food and noted which hand the animals used to hold the tubes and which hand the animals used to remove ...
Josselyn S A - - 1996
Cholecystokinin (CCK) is an endogenous peptide that is colocalized with dopamine (DA) in some mesolimbic neurons projecting to the nucleus accumbens (NAC). DA has been implicated in the acquisition of conditioned rewarding properties by neutral stimuli [conditioned stimuli (CS)] associated with a primary reward (such as food). A variety of ...
McGraw W S - - 1996
Habitat heterogeneity is widely theorized to be important in the evolution of Old World monkeys, yet the impact of architecturally distinct forest types on the positional repertoires of African monkeys is largely unknown. As part of a wider project, this study investigates how the locomotor behavior of five sympatric cercopithecids ...
Spooren W P - - 1996
This study describes the organization of the ventral and dorsal pallidostriatal pathway in the monkey. Both retrograde and anterograde tracers were injected into various regions of the ventral and dorsal pallidum as well as into the striatum. The data indicate that the pallidostriatal pathway is an extensive pathway in the ...
Bauman R A - - 1996
Three experiments were conducted to study the effect of an imperfect substitute for food on demand for food in a closed economy. In Experiments 1 and 2, rats pressed a lever for their entire daily food ration, and a fixed ratio of presses was required for each food pellet. In ...
Rauth-Widmann B - - 1996
Long-term recordings of locomotor activity, feeding activity and core temperature carried out in 7 male and 7 female adult owl monkeys (Aotus lemurinus griseimembra) revealed sex-specific infradian alterations in the level of these circadian functions when the monkeys were housed under lighting conditions which neither inhibited nor enhanced (i.e., "masked,") ...
Berridge K C KC Department of Psychology, University of Michigan, Ann Arbor - - 1996
What are the neural substrates of food reward? Are reward and pleasure identical? Can taste pleasure be assessed in animals? Is reward necessarily conscious? These questions have re-emerged in recent years, and there is now sufficient evidence to prompt re-examination of many preconceptions concerning reward and its relation to brain ...
Parker A - - 1995
Three Cynomolgus monkeys (Macaca fasicularis) learned a series of food-visual conditional discrimination problems. In each problem, 1 of 2 possible food items was presented at the beginning of each trial and acted as an instruction cue as to which of 2 visually distinct stimulus objects the monkey must displace on ...
Howland D R - - 1995
The development of bipedal treadmill locomotion and overground locomotion has previously been studied in the kitten; the development of quadrupedal treadmill locomotion has not. We evaluated and compared all three forms of locomotion in the normal kitten and present quantitative data comparing the development of quadrupedal treadmill and overground locomotion. ...
Mohdmarjan Z Z - - 1995
The purpose of this study was to develop a visual aid to improve and increase accuracy of the 24-hour recall method. This aid in the form of a booklet, consists of life-sized photographs of common Malaysian foods, accompanied by the weight of its edible portion and nutrient values. These photographs ...
De Vleeschouwer K - - 1995
The effect of posture on hand preferences was examined in an experiment with 5 bonobos (Pan paniscus). To obtain a food reward, the animals had to adopt 1 out of 7 different postures. These postures represented an increasing problem to the maintenance of body equilibrium. It was expected that an ...
Comer S D - - 1995
Studies have shown that both food deprivation and response cost have important influences on the magnitude of self-administration of a wide variety of psychoactive drugs. In an attempt to extend these findings to the smoked route of drug self-administration, the effects of food allotment and fixed-ratio (FR) value were evaluated ...
Aou S - - 1994
Although the dopamine (DA) system has been shown to regulate food intake, the function of the DA receptor subtypes on behavior still remains to be elucidated. In the present study, we examined the effect of B-HT 920, a selective agonist of DA D2 receptors that preferentially affect presynaptic autoreceptors, on ...
Roney L S - - 1993
Squirrel monkeys (Saimiri sciureus) and cotton-top tamarins (Saguinus oedipus) made unimanual food reaches from either a horizontal, quadrupedal posture or a vertical, clinging posture. No population-level handedness occurred in either species. However, in both species, directional lateral preferences weakly expressed for reaching from the stable quadrupedal posture were intensified in ...
Champoux M - - 1993
Laboratory-born, group-housed, ovariectomized adult female squirrel monkeys (Saimiri sciureus) were exposed to feeding conditions in which the availability and accessibility of food were altered. Both high- and variable-demand feeding conditions were utilized. The variable-demand condition required alternating periods of high effort (120% of normal daily intake presented) and low effort ...
Hopkins W D - - 1993
Behavioral laterality was studied in a captive group of 11 bonobos (Pan paniscus). In an observational method a significant left lateral bias in carrying and a right lateral bias in leading limb were found. Direction of lateral bias in carrying and leading limb was enhanced when subjects maintained a bipedal ...
Corwin R L - - 1993
The present report describes a new procedure for assessing anorectic specificity. Two rhesus monkeys (Macaca mulatta) surgically prepared with indwelling intragastric catheters were trained in a discrete trial choice paradigm to respond for either food or visual access to a room containing other monkeys. Our hypothesis was that a specific ...
Schreihofer D A - - 1993
Short periods of fasting (1-2 days) significantly suppress the frequency of pulsatile LH secretion in adult male rhesus monkeys. Resumption of food intake (i.e. refeeding) after fasting rapidly restores pulsatile LH secretion. We hypothesized that the resumption of LH secretion after refeeding results from the metabolic consequences of food intake ...
Demaria-Pesce V H - - 1993
Previous experiments performed with mammals during spaceflight suggest that microgravity may affect the circadian timekeeping system. However, this system could also be influenced by other factors related to the spaceflight environment, such as the animal compartment. The Rhesus project is a joint program of C.N.E.S. and N.A.S.A in which investigators ...
Cherpas C - - 1993
Michael (this issue) defines an establishing operation (EO), such as food deprivation, as (a) altering the effectiveness of reinforcement as well as (b) evoking behavior. Although this dual role for EOs is compelling, it is possible that such operations have only evocative effects (i.e., function only in the form of ...
Yoshida M - - 1993
The effect of chronic administration of a probable endogenous dopaminergic neurotoxin, tetrahydroisoquinoline, has been examined on squirrel monkeys. Chronically administered TIQ produced motor symptoms similar to parkinsonism in squirrel monkeys even 7 days after discontinuation of TIQ and the symptoms were alleviated remarkably by L-DOPA treatment. Biochemical analysis of the ...
Hauser M D - - 1992
From a functional perspective, deception can evolve in animal populations but should be constrained by the costs associated with detection. It then follows that withholding information should be more prevalent as a form of deception than active falsification of information because of the relative difficulties associated with detecting cheaters. Empirical ...
Nader M.A. - - 1992
The present experiment was designed to examine the effects of the conditions of food availability on choice between cocaine and food in rhesus monkeys. Monkeys (n = 3), maintained at approximately 90% of their free-feeding weights, were trained in a discrete-trials choice procedure and allowed to choose between intravenous injections ...
Bard K A - - 1992
The goal of this study was to describe the ontogeny of the manipulation of an animate object (i.e., the mother) by young free-ranging orangutans within the context of food sharing. The food-sharing context is an important one in the development of object manipulation skills and social communication. 5 orangutans, ranging ...
Sinnott J M - - 1992
Frequency (delta F) and intensity (delta I) difference limens were directly compared in Mongolian gerbils (Meriones unguiculatus), Old World African Monkeys (Cercopithecus mitis, Cercocebus albigena), and humans. Methods employed a repeating background AX discrimination procedure, and positive (food) reinforcement for animals. For delta I, there were small quantitative differences between ...
Povinelli D J - - 1991
The ability of 4 rhesus monkeys (Macaca mulatta) to understand the causal connection between seeing and knowing was investigated. The subjects were tested to determine if they could discriminate between information provided by experimenters who randomly alternated between roles of guesser and knower. In a series of tests, the knower ...
Tamura R - - 1991
To investigate the role of the hippocampal formation (HF) in feeding behavior, single neuron activity in the monkey HF was recorded during performance of an operant task that included food/nonfood discrimination, drinking, and active avoidance. Of 837 neurons recorded in the HF, 155 responded to the sight of one or ...
Washburn D A - - 1991
Two rhesus monkeys (Macaca mulatta) learned that the arabic numerals 0 through 9 represented corresponding quantities of food pellets. By manipulating a joystick, the monkeys were able to make a selection of paired numerals presented on a computer screen. Although the monkeys received a corresponding number of pellets even if ...
Hannah J - - 1990
To investigate the role of plasma insulin on food intake, we have examined the effect of naturally occurring chronic hyperinsulinemia on the feeding behavior of male rhesus monkeys. Two groups of monkeys, a group with normal fasting insulin concentrations (52.4 +/- 2.2 microU/ml) (mean +/- SE) and a hyperinsulinemic group ...
Povinelli D J - - 1990
The visual perspective-taking ability of 4 chimpanzees (Pan troglodytes) was investigated. The subjects chose between information about the location of hidden food provided by 2 experimenters who randomly alternated between two roles (the guesser and the knower). The knower baited 1 of 4 obscured cups so that the subjects could ...
Hayes S L - - 1990
Capuchin monkeys often employ complex manipulative skills while recovering food items. Five captive Cebus capucinus were presented with two identical feeders that required the monkeys to lift up flaps, search through hay, and perform coordinated hand movements in order to obtain food items. The intent of this study was not ...
Welsh D K - - 1990
Lithium lengthens the period of free-running circadian rhythms in a variety of species, but this effect has not been demonstrated unequivocally in primates. Because of the possible link between lithium's action on the circadian clock and its therapeutic action in human mood disorders, we tested the ability of lithium to ...
Line S W - - 1990
Environmental enrichment devices are a potential way to enhance psychological well-being in laboratory animals. The effects of such devices need to be systematically evaluated before they are recommended for widespread use. The purpose of this research was to monitor the behavioural and physiological responses of adult female rhesus macaques to ...
Wissler R W - - 1990
For at least 60 years, spotty and poorly documented evidence has suggested that atherosclerotic disease in humans might be reversible. Little direct evidence was available until researchers demonstrated that rather advanced atherosclerotic lesions in experimental animals could show marked improvement after blood-lipid-reducing regimens that were often combined with other measures, ...
Lawes M J - - 1990
The samango monkey occurs at the southern limit of the range of Cercopithecus mitis. Greater climatic seasonality at this latitude results in more predictable fruiting patterns. In addition, there are no diurnal sympatric primate frugivores. Under these conditions, the diet and feeding strategies of samango monkeys would be expected to ...
Chapman C A - - 1990
The foraging strategies and association patterns of 3 species of primates (Ateles geoffroyi, Alouatta palliata, Cebus capucinus) were studied over a 5-year period. The objective of the study was to provide a quantitative test of the hypothesis that the size, density and distribution of food resources influence the size of ...
Boesch C - - 1990
Reported incidences of tool use and tool making for three wild chimpanzee populations increase from Mahale (12 and 3 types of use and making, respectively), Gombe (16 and 3) to Taï (19 and 6). Sticks are commonly used and prepared at all three sites. However, Taï chimpanzees seem to perform ...
Feistner A T - - 1990
Food-sharing behaviour was observed in 9 captive families of cotton-top tamarins (range 4-14 individuals per group), during meals of fresh fruit. Food was transferred to infants by their parents and older sibs in response to begging, and was also offered to them without prior solicitation. Older, mature, reproductively suppressed individuals ...
Evans K R KR University of Toronto, Department of Psychology, - - 1990
The present study examined the possibility that the increased feeding found following central and peripheral administrations of low doses of d-amphetamine (AMP) and morphine (MOR) may involve central reward mechanisms. In order to examine this possibility, the effects of these drugs on food selection and intake of foods that varied ...
Katz N L - - 1989
The present study examined the effect of structural analogs of clonidine on feeding in both rabbits and monkeys. In rabbits, lofexidine and tizanidine either did not influence or decreased food intake in contrast to clonidine, which stimulated food intake. Lofexidine elicited easily observed decreases in motor behavior with several of ...
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