Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Cebus”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 253 records · Page 14Linked to original sources
PubMed2000

Solving a cooperation task without taking into account the partner's behavior: the case of capuchin monkeys (Cebus apella).

Four pairs of tufted capuchin monkeys (Cebus apella) were tested in a task requiring that both partners pull a handle simultaneously in order for both to be rewarded. The experimental design, an improved version of that of R. Chalmeau, E. Visalberghi, and A. Gallo (1997), aimed at assessing the extent to which a monkey that is pulling takes account of the behavior and spatial position of its partner, that is, whether the monkey understands what cooperation involves. Although all pairs succeeded, pulling was not affected by the partner's behavior, and it was affected only to a certain extent by the partner's spatial position. In addition, more experienced capuchins did not outperform naive individuals. The finding that capuchins were successful without understanding the role of the partner suggests that their cooperation is not cognitively grounded, as has been argued in descriptions of the hunting behavior of wild capuchins.

Animals↗
PubMed2004

Socially learned preferences for differentially rewarded tokens in the brown capuchin monkey (Cebus apella).

Social learning is assumed to underlie traditions, yet evidence indicating social learning in capuchin monkeys (Cebus apella), which exhibit traditions, is sparse. The authors tested capuchins for their ability to learn the value of novel tokens using a previously familiar token-exchange economy. Capuchins change their preferences in favor of a token worth a high-value food reward after watching a conspecific model exchange 2 differentially rewarded tokens, yet they fail to develop a similar preference after watching tokens paired with foods in the absence of a conspecific model. They also fail to learn that the value of familiar tokens has changed. Information about token value is available in all situations, but capuchins seem to pay more attention in a social situation involving novel tokens.

Animals↗
PubMed2004

Use of visual, acoustic, and olfactory information during embedded invertebrate foraging in brown capuchins (Cebus apella).

Experiments were conducted to investigate which sensory cues are used by brown capuchins (Cebus apella) in embedded invertebrate foraging. The importance of visual, olfactory, and acoustic cues in such foraging was determined by presenting subjects with a stimulus log modified to block out given sensory cues. Experiment 1 was designed to investigate whether subjects could locate an invertebrate embedded in wood when only visual, acoustic, or olfactory information was available. Experiments 2 and 3 were designed to investigate extractive foraging behavior when two sensory cues were provided. It was hypothesized that the combination of visual and acoustic information would be necessary for subjects to successfully locate embedded invertebrates. Results indicated that subjects' performance was most successful when both visual and acoustic information was available.

Animals↗
PubMed2004

Detection of grouped and ungrouped parts in visual patterns by tufted capuchin monkeys (Cebus apella) and humans (Homo sapiens).

The authors investigated perceptual grouping in capuchin monkeys (Cebus apella) and humans (Homo sapiens). In Experiment 1, 6 monkeys received a visual pattern as the sample and had to identify the comparison stimulus featuring some of its parts. Performance was better for ungrouped parts than for grouped parts. In Experiment 2, the sample featured the parts, and the comparison stimuli, the complex figures: The advantage for ungrouped elements disappeared. In Experiment 3, in which new stimuli were introduced, the results of the previous experiments were replicated. In Experiment 4, 128 humans were presented with the same tasks and stimuli used with monkeys. Their accuracy was higher for grouped parts. Results suggest that human and nonhuman primates use different modes of analyzing multicomponent patterns.

Animals↗
PubMed2004

Responses of white-faced capuchins (Cebus capucinus) to naturalistic and experimentally presented food-associated calls.

In the context of foraging, many animal species produce specific calls that attract others. Researchers hypothesize that these vocalizations function to inform others about food; however, few studies have investigated whether food-associated calls alone are sufficient to cause individuals to respond as if they have been informed about food. Playback experiments on white-faced capuchins (Cebus capucinus) investigated whether listeners could infer the presence of food merely by hearing food-associated calls. Recipients looked significantly longer toward the call source and approached the speaker more often after hearing food-associated calls, as compared with control calls. Because these responses are not indicative of feeding, it is unclear whether listeners associated the calls with food. Nonetheless, these responses, specific to food-associated calls, may increase individuals' chances of finding food.

Acoustic Stimulation↗
PubMed2004

Categorization of above and below spatial relations by tufted capuchin monkeys (Cebus apella).

Using a matching-to-sample procedure, the researchers investigated tufted capuchins' (Cebus apella) ability to form categorical representations of above and below spatial relations. In Experiment 1, 5 capuchins correctly matched bar-dot stimuli on the basis of the relative above and below location of their constituent elements. The monkeys showed a positive transfer of performance both when the bar-dot distance in the two comparison stimuli differed from that of the sample and when the actual location of the matching stimulus and the nonmatching stimulus on the apparatus was modified. In Experiment 2, the researchers systematically changed the shapes of the located object (the dot) or the reference object (the horizontal bar). These manipulations did not affect the monkeys' performance. Overall, the data suggest that capuchins can form abstract, conceptual-like representations for above and below spatial relations.

Animals↗
PubMed2005

A comparative analysis of global and local processing of hierarchical visual stimuli in young children (Homo sapiens) and monkeys (Cebus apella).

Results obtained with preschool children (Homo sapiens) were compared with results previously obtained from capuchin monkeys (Cebus apella) in matching-to-sample tasks featuring hierarchical visual stimuli. In Experiment 1, monkeys, in contrast with children, showed an advantage in matching the stimuli on the basis of their local features. These results were replicated in a 2nd experiment in which control trials enabled the authors to rule out that children used spurious cues to solve the matching task. In a 3rd experiment featuring conditions in which the density of the stimuli was manipulated, monkeys' accuracy in the processing of the global shape of the stimuli was negatively affected by the separation of the local elements, whereas children's performance was robust across testing conditions. Children's response latencies revealed a global precedence in the 2nd and 3rd experiments. These results show differences in the processing of hierarchical stimuli by humans and monkeys that emerge early during childhood.

Animals↗
PubMed2005

Experience and materials affect combinatorial construction in tufted capuchin monkeys (Cebus apella).

Three movement procedures can combine nesting cups into seriated structures. Reliance on these procedures changes with age in human children, and the putatively most advanced emerges as a predominant procedure at 3 or more years. Six monkeys' (Cebus apella) combinatorial procedures and successes at nesting seriated cups were evaluated. The current study examined whether the procedures used (a) shift toward more efficient procedures after unguided experience, (b) are dependent on the type of object being combined, and (c) can be altered by specific training history. All factors produced a change in procedure for some individuals, suggesting that combinatorial procedure is a product of the dynamic influences of preexisting tendencies to act in certain ways, of environmental circumstances, and of prior experiences. Some monkeys preferred the putatively most cognitively complex procedure.

Animals↗
PubMed2005

Choosing and using tools: capuchins (Cebus apella) use a different metric than tamarins (Saguinus oedipus).

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) preferred canes they could pull straight in when these were present, but they also repositioned canes in individually variable ways, and their success at obtaining food with repositioned canes improved with practice. In accord with predictions drawn from ecological psychology, capuchins discovered affordances of canes through exploratory actions with these objects, whereas tamarins did not. Ecological theory predicts these differences on the basis of species-typical manipulative activity, and it provides a useful approach for the study of species differences in tool-using behavior.

Animals↗
PubMed2005

Cooperative problem solving by tufted capuchin monkeys (Cebus apella): spontaneous division of labor, communication, and reciprocal altruism.

Using an experimentally induced cooperation task, the authors investigated whether tufted capuchin monkeys (Cebus apella) share the following 3 characteristics of cooperation with humans: division of labor, communication, and reciprocal altruism. In Experiment 1, the authors trained individual monkeys to perform the necessary sequence of actions for rewards and tested them in pairs to assess whether they could solve the task by spontaneously dividing the sequence of actions. All pairs solved this task. In Experiment 2, monkeys worked in the cooperation task and a task requiring no partner help. They looked at the partner significantly longer in the former task than in the latter, but communicative intent could not be determined. In Experiment 3, only 1 of 2 participants obtained a reward on each trial. Monkeys maintained cooperation when their roles were reversed on alternate trials. Their cooperative performances demonstrated division of labor; results suggest task-related communication and reciprocal altruism.

Altruism↗
PubMed2005

Attention to combined attention in new world monkeys (Cebus apella, Saimiri sciureus).

Co-orientation by capuchin (Cebus apella) and squirrel (Saimiri sciureus) monkeys in response to familiar humans abruptly switching the direction of their visual attention was recorded. Co-orientation occurred more frequently overall in capuchins than squirrel monkeys. Capuchins showed a tendency to habituate within trials involving consecutive attention switches performed by 2 different people, whereas squirrel monkeys co-oriented more when the 2nd attention switch was by a 2nd actor. These results suggest variable attention-processing abilities in New World monkeys, including differences in summation of attention by others.

Animals↗
PubMed2006

Self-control and tool use in tufted capuchin monkeys (Cebus apella).

Self-control is defined as forgoing immediate gratification to obtain a greater reward. Tool use may relate to self-control because both behaviors may require foresight and deliberate control over one's actions. The authors assessed 20 capuchin monkeys (Cebus apella) for the ability to delay gratification in a tool task. Subjects were given rod-shaped food items that could either be consumed immediately or be carried to an apparatus and used to extract a more preferred food. The authors found that some monkeys were able to exhibit self-control. Monkeys with relatively more tool use experience demonstrated the greatest levels of self-control. These results indicate that capuchins are capable of delaying gratification when a higher quality reinforcer is present and that tool experience can influence levels of self-control in this task.

Age Factors↗
PubMed2006

How capuchin monkeys (Cebus apella) quantify objects and substances.

Humans and nonhuman animals appear to share a capacity for nonverbal quantity representations. But what are the limits of these abilities? Results of previous research with human infants suggest that the ontological status of an entity as an object or a substance affects infants' ability to quantify it. We ask whether the same is true for another primate species-the New World monkey Cebus apella. We tested capuchin monkeys' ability to select the greater of two quantities of either discrete objects or a nonsolid substance. Participants performed above chance with both objects (Experiment 1) and substances (Experiment 2); in both cases, the observed performance was ratio dependent. This finding suggests that capuchins quantify objects and substances similarly and do so via analog magnitude representations.

Animals↗
PubMed2005

Primary motor cortex asymmetry is correlated with handedness in capuchin monkeys (Cebus apella).

Humans exhibit a population-wide tendency toward right-handedness, and structural asymmetries of the primary motor cortex are associated with hand preference. Reported are similar asymmetries correlated with hand preference in a New World monkey (Cebus apella) that does not display population-level handedness. Asymmetry of central sulcus depth is significantly different between left-handed and right-handed individuals as determined by a coordinated bimanual task. Left-handed individuals have a deeper central sulcus in the contralateral hemisphere; right-handed individuals have a more symmetrical central sulcus depth. Cerebral hemispheric specialization for hand preference is not uniquely human and may be more common among primates in general.

Animals↗
PubMed2003

Cebus apella, a nonhuman primate highly susceptible to neuroleptic side effects, carries the GLY9 dopamine receptor D3 associated with tardive dyskinesia in humans.

Tardive dyskinesia (TD) is a severe side effect of traditional neuroleptics affecting a considerable number of schizophrenic patients. Accumulating evidence suggests the existence of a genetic disposition to TD and other extra pyramidal symptoms (EPS) most strongly linked to a ser/gly polymorphism in position 9 of the D3 dopamine receptor gene (DRD3). The Cebus apella monkey is the favored animal model to study TD and other EPS because of its high susceptibility to side effects of neuroleptics. We therefore determined the sequence of the DRD3 gene in this species and compared it with that of humans. We found that the highly TD susceptible C. apella monkey (n=21) carries the gly9/gly9 DRD3 genotype that has been associated with TD in humans. Contrarily, C. apella did not carry the ser23 5HT2C allele that has been reported to increase TD susceptibility in humans.

Amino Acid Substitution↗
PubMed1999

Local and systemic cytokine expression during experimental chronic Trypanosoma cruzi infection in a Cebus monkey model.

Cebus apella is an acceptable model for chronic chagasic cardiomyopathy (CCC), since it is possible to experimentally induce cardiac lesions after 1 year of Trypanosoma cruzi infection. The T. cruzi Y strain, shown previously to produce CCC in C. apella monkeys, was used to experimentally infect 10 monkeys. Parasitological, serological and clinical parameters were monitored during a 19-month follow-up, and systemic cytokine responses were assessed sequentially in five monkeys selected according to the differential parasitemia pattern exhibited. Ten additional monkeys, infected with the same strain for 5, 10 and 12 years, were analysed cross-sectionally. Three monkeys/time point and one uninfected control animal were sacrificed for gross pathology, histology, presence of parasites, and local cytokine gene expression. Elevated expression of interleukin (IL)-4 was observed throughout the study in monkeys that had persistent, high parasitemias, whereas a high level of interferon (IFN)-gamma was seen in monkeys that controlled parasitemias soon after infection. Chronically infected monkeys expressed a nonpolarized, Th0-type response. Cardiac tissue collected from a monkey that succumbed to acute infection had elevated levels of proinflammatory cytokine [IL-1beta, IL-6, tumour necrosis factor-alpha] and interstitial cell adhesion molecule (ICAM)-1, platelet-derived growth factor (PDGF)-alpha, transforming growth factor (TGF)-beta and IL-10 transcripts. Cytokine production in cardiac tissue of chronically infected monkeys was also characterized by elevated expression of ICAM-1, PDGF-alpha and TGF-beta, which correlated with the detection of T. cruzi DNA by polymerase chain reaction.

Acute Disease↗
PubMed2003

Frontal sinus obliteration with heterogeneous corticocancellous bone versus spontaneous osteoneogenesis in monkeys (Cebus apella): histologic analysis.

PURPOSE: In this study, we evaluated the results of spontaneous osteoneogenesis of the frontal sinus with autogenous bone plug versus obliteration with heterogeneous (human) bone in monkeys (Cebus apella). MATERIALS AND METHODS: Eight young adult male C apella monkeys underwent an ostectomy of the anterior wall of the frontal sinus, removal of the sinus mucosa, and inner decortication of the bony walls and then were divided into 2 groups of 4 each, as follows. Group I monkeys underwent obliteration of the nasofrontal ducts with a free segment of frontallis muscle and corticocancellous heterogeneous bone, followed by full obliteration of the sinus with corticocancellous heterogeneous bone (Dayton Regional Tissue Bank, Dayton, OH). Group II monkeys underwent obliteration of the nasofrontal ducts with a frontal muscle segment and tibial autogenous bone plug, without full obliteration of the frontal sinus. In all animals, the sinus anterior wall was repositioned and fixed with 1.0 plate and screws. The monkeys were killed after 180 days, and routine laboratory procedures were followed for hematoxylin-eosin staining and histologic evaluation of the specimens. RESULTS: The 2 studied techniques were both effective in obliterating the frontal sinus with newly formed bone. The nasofrontal ducts were obliterated by new bone formation or fibrous tissue (1 animal only). CONCLUSIONS: Both methods used for frontal sinus obliteration were effective; the heterogeneous bone (human bone) was well tolerated and presented low antigenicity. The nasofrontal duct obliteration with autogenous muscle associated with autogenous tibial bone (group II) or with heterogeneous bone (group I) was effective, isolating the frontal sinus from the nasal cavity. The spontaneous obliteration resulted, in the period analyzed, in earlier bone maturation compared with the obliteration by heterogeneous bone.

Adipose Tissue↗
PubMed1956

Effect of the level and type of dietary fat on the metabolism of cholesterol and beta lipoproteins in the Cebus monkey.

A study was carried out to determine the effect of the level and type of dietary fat on the concentration of cholesterol and beta lipoproteins in the sera of Cebus monkeys. Three groups of monkeys were fed isocaloric diets containing a fixed ratio of alpha protein and cholesterol to calories but with different amounts of corn oil and sucrose. Corn oil provided 10, 32, and 45 per cent of the calories in the three diets, and the level of sucrose was varied inversely. After 8 weeks the serum cholesterol and S(f) 12 to 100 beta lipoprotein concentrations were significantly greater in the medium and high fat groups. When corn oil was decreased from 45 to 10 per cent of dietary calories and sucrose was increased, the serum cholesterol fell in all cases, and when the reverse change was made, the concentration of serum cholesterol increased. Variation in dietary sucrose had no specific effect. Substitution of starch for sucrose with diets otherwise constant did not cause significant change in the concentration of serum cholesterol. When monkeys fed corn oil diets at any of three levels were changed to hydrogenated cottonseed oil diets at the same level, the serum cholesterol and S(f) 12 to 100 beta lipoproteins rose. However, hydrogenated cottonseed oil had no greater hypercholesteremic effect than did corn oil in the absence of dietary cholesterol. Diets containing lard with cholesterol also produced strikingly greater serum lipide responses than did diets based on corn oil and cholesterol. Hydrogenated cottonseed oil had a greater hypercholesteremic effect than an unhydrogenated cottonseed oil from the same lot. Preliminary studies indicated that the saturated fats (hydrogenated cottonseed oil) produced the most striking elevation of serum cholesterol values (above controls fed corn oil) when casein was the dietary protein.

Animals↗