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Results 451 - 500 of 615
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Nakagawa N - - 1999
In order to obtain reliable evidence for differences in habitat preferences between two closely related savanna-dwelling primate species, namely, patas monkeys (Erythrocebus patas) and tantalus monkeys (Cercopithecus aethiops tantalus), I collected data on vegetation and patterns of range use concurrently at a single study site, Kala Maloue, Cameroon, in a ...
Hauser MD - - 1999
In any problem-solving situation, there are features associated with the problem that are relevant from a functional perspective and other features that are irrelevant. To determine whether animals are sensitive to the distinction between functionally relevant and irrelvant features of a problem, we conducted two main experiments with a New ...
Beran M J MJ Language Research Center, Georgia State University Decatur 30034, - - 1999
Delay of gratification in 3 chimpanzees (Pan troglodytes) was examined by using a paradigm based on research with children. The chimpanzees either pressed a door-bell button during a trial and received one reward (the immediate reward) or did not press the doorbell and received another reward (the delayed reward). Two ...
Bassareo V V Department of Toxicology and CNR, Center for Neuropharmacology, University of Cagliari, - - 1999
The nucleus accumbens septi is the major target of mesolimbic dopamine neurons originating in the ventral tegmental area of the mesencephalon. Studies involving experimental manipulation of dopamine transmission by drugs and by lesions, as well as in vivo monitoring of extracellular dopamine concentrations, have provided evidence that the dopamine transmission ...
Pakarinen E D - - 1999
The present study assessed the liability of ethanol to be established as an oral reinforcer in 24 juvenile rhesus monkeys. All of the monkeys had a prior oral self-administration history with concurrently available methadone and water. To determine if food restriction and sex differences would contribute to ethanol preference, the ...
Estrada A - - 1999
In Neotropical rain forests, fresh mammal dung, especially that of howler monkeys, constitutes an important resource used by dung beetles as food and for oviposition and further feeding by their larvae. Tropical rain forest destruction, fragmentation, and subsequent isolation causing reductions in numbers of and the disappearance of howler monkeys ...
Laska M - - 1999
The purpose of this study was to determine taste difference thresholds for sucrose in frugivorous spider monkeys and omnivorous baboons. Using a two-bottle preference test of brief duration, we presented four Ateles geoffroyi and four Papio hamdryas anubis with six different reference concentrations (RCs) of 25, 50, 100, 200, 300, ...
Miyazaki K K Laboratory of Brain-operative expression, Brain Science Institute, RIKEN, Wako, Saitama, - - 1998
Single unit recording in rat nucleus accumbens (NAcc) was used to ascertain NAcc neuronal activity in mediating of reward including its anticipation. Of the 103 neurons investigated, 63% showed some response in connection with the task activity. Of these, 20 units responded during delivery of the primary reward (food and/or ...
Tomie A A Department of Psychology, Center of Alcohol Studies, Rutgers University, Piscataway, NJ 08855, - - 1998
Autoshaping conditioned responses (CRs) are reflexive and targeted motor responses expressed as a result of experience with reward. To evaluate the hypothesis that autoshaping may be a form of impulsive responding, within-subjects correlations between performance on autoshaping and impulsivity tasks were assessed in 15 Long-Evans hooded rats. Autoshaping procedures [insertion ...
Parker A - - 1998
Three Cynomolgus monkeys (Macaca fascicularis) learned a flavour-visual conditional discrimination problem, in which one of two possible food items was presented at the beginning of each trial, and acted as an instruction cue to signal which of two visually distinct stimulus objects the animal must displace on that trial in ...
Silberberg A - - 1998
In 5 experiments, 4 monkeys and 1 ape chose between 2 food sources, each held in 1 of the experimenter's hands while he stood in front of a cage. When choosing between 2 sources of the same food that differed in amount, preference for the larger amount decreased as the ...
Hopkins W D - - 1998
Hand use in gestural communication was examined in 115 captive chimpanzees (Pan troglodytes). Hand use was measured in subjects while they gestured to food placed out of their reach. The distribution of hand use was examined in relation to sex, age, rearing history, gesture type, and whether the subjects vocalized ...
Novak M A - - 1998
Self-injurious behavior (SIB) occurs in about 10% of individually housed monkeys. Monkeys with SIB bite their own bodies frequently, occasionally inflicting wounds as a result. At present, there is no standard treatment for this phenomenon. We examined the effectiveness of puzzle feeders in alleviating SIB in monkeys with a veterinary ...
Visalberghi E - - 1998
Visalberghi and Fragaszy [Animal Behaviour 49:1089-1095, 1995] have shown that social influences affect acceptance of novel foods. However, little is known about the temporal course on which such influences act (e.g., for how long they persist and for how many encounters they are effective). To explore this issue, 11 adult ...
Isbell L A - - 1998
A 17 month field study of unprovisioned patas monkeys (Erythrocebus patas pyrrhonotus) in Laikipia, Kenya, using both ad libitum and scan sampling techniques, revealed that the diet of patas monkeys consists primarily of gum of Acacia drepanolobium, arthropods (both free-living and concentrated in the swollen thorns of A. drepanolobium), and ...
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 ...
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