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Results 501 - 550 of 612
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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 ...
Evans S M - - 1989
Pigeons were trained to discriminate i.m. administered d-amphetamine (AMPH) or pentobarbital (PB) from saline with responding maintained under a fixed-ratio 30 schedule of food delivery. Rhesus monkeys were trained to discriminate intragastrically administered AMPH or PB from saline using a signaled shock-avoidance trial procedure. In AMPH-trained pigeons the histamine H1-antagonists ...
Milliken G W - - 1989
Evaluated a free-ranging matriline of 13 ring-tailed lemurs (Lemur catta) from videotaped records for lateralized hand use with 2 tasks and 4 measures: food reaching, feeding posture, duration of food holding, and manipulation of food between mouth and hand while eating. Binomial z scores determined 7 lemurs to be left ...
Binienda Z - - 1989
We studied the hormonal responses in four pregnant rhesus monkeys between 112 and 149 days gestation. After 2 days, during which the monkeys were fed ad libitum, their food was withdrawn at 1500 h for 48 h while allowing free access to water. The food then was returned, and the ...
Kemnitz J W - - 1989
The influences of ovarian hormones on food intake, taste preferences, and glucoregulation were examined in intact and ovariectomized rhesus monkeys. Intake of intact monkeys was lowest in the preovulatory stage of the cycle, when estrogen levels are elevated, and exogenous estradiol transiently suppressed food intake of ovariectomized monkeys in a ...
Marriott B M - - 1989
The food ingestion patterns of the rhesus monkeys (Macaca mulatta) of Group L on Cayo Santiago were quantitatively recorded during two months which coincided with the annual breeding season. Three methods of sampling were used concurrently: interval scan sampling, group location mapping and focal animal observation. These data generated time ...
Evans M A - - 1989
A field project was conducted to remove an introduced population of rhesus macaques (Macaca mulatta) from Desecheo Island National Wildlife Refuge, Puerto Rico. A group of 57 monkeys from Cayo Santiago was released on Desecheo Island in 1966 to study processes of adaptation. Observations in 1969 and 1970 implicated the ...
Boysen S T - - 1989
A chimpanzee (Pan troglodytes), trained to count foods and objects by using Arabic numbers, demonstrated the ability to sum arrays of 0-4 food items placed in 2 of 3 possible sites. To address representational use of numbers, we next baited sites with Arabic numbers as stimuli. In both cases performance ...
Binienda Z - - 1989
Pregnant rhesus monkeys were studied between 109 and 149 days of gestation. Food withdrawal for 48 hours (with free access to water) was accompanied by a decrease in maternal whole blood glucose concentration and an increased maternal arterial plasma 13,14-dihydro-15-keto-prostaglandin F2 alpha concentration. On successive nights of the 48-hour period ...
Adamson R H - - 1989
Several compounds were evaluated in nonhuman primates for their potential to induce neoplasms, especially hepatocellular carcinoma (HCC). The compounds can be classified into three groups: food contaminants, model rodent carcinogens, and nitrosamines. All three compounds in the food contaminants group, namely, aflatoxin B1, sterigmatocystin, and methylazoxymethanol acetate, induced HCC. None ...
Fonberg E - - 1988
Dominance is a complex phenomenon mediated by different mechanisms. Various motivations and their mutual correlations determine the tendency to dominate. A subject that is dominant in every situation (i.e., absolutely dominant) is rather an exceptional case. Dominance may be limited to particular situations and exhibited only with some definite partners. ...
Clifton P G - - 1988
Chicks trained to take a food reward at the end of a runway can be distracted by changes in the appearance of either the food dish towards which they are running or of the walls of the runway remote from the food dish. Testosterone (administered as a long lasting ester ...
Sunderland G - - 1988
The taste preferences of adult male squirrel monkeys and bonnet macaques for Polycose, maltose, and sucrose solutions were compared in 24 hr/day solution vs. water tests. Solution concentrations of 0.01 M, 0.05 M, 0.10 M, and 0.20 (Polycose) or 0.50 M (maltose and sucrose) were tested. The squirrel monkeys displayed ...
Hernandez L L Department of Psychology, Princeton University, New Jersey - - 1988
Dopamine was measured by microdialysis in the nucleus accumbens of freely moving rats while they experienced rewarding food, brain stimulation and drugs. Extracellular dopamine increased 37% when the animals pressed a lever for food reward. Electrical stimulation of a lateral hypothalamic feeding-reward (self-stimulation) site caused a similar increase in dopamine, ...
Chamberlain B - - 1987
Social groups of vervet monkeys (Cercopithecus aethiops) were given amino acid mixtures that were tryptophan-free (T-), nutritionally balanced (B), or contained excess tryptophan (T+). The T- mixture caused a marked decrease in plasma tryptophan and the T+ mixture a large increase. Behavioral observations were made on the animals after administration ...
Sinnott J M - - 1987
Humans and monkeys were compared in their differential sensitivity to various acoustic cues underlying voicing contrasts specified by voice-onset time (VOT) in utterance-initial stop consonants. A low-uncertainty repeating standard AX procedure and positive-reinforcement operant conditioning techniques were used to measure difference limens (DLs) along a VOT continuum from--70 ms (prevoiced/ba/) ...
Wilpizeski C R - - 1987
It has been suggested by numerous researchers that the development of conditioned food aversion (CFA) in experimental animals represents the presence of a subjective state of illness. Squirrel monkeys with proven susceptibility to rotation-induced vomiting were given surgical bilateral labyrinthectomies, a procedure known to abolish signs and symptoms of motion ...
Sinnott J M - - 1987
Auditory duration DLs at 2.0 kHz were measured in Old World monkeys (Macaca, Cercopithecus) and humans using a go, no-go repeating standard AX procedure and positive reinforcement operant conditioning techniques. For a 200-ms standard, monkey DLs were 45-125 ms, compared to 15-27 ms for humans. Weber fractions (delta T/T) for ...
Carroll M E - - 1987
Two experiments addressed the effects of food satiation and deprivation on oral self-administration of two concurrently available phencyclidine concentrations. In the first experiment, 8 rhesus monkeys self-administered either of two concentrations of phencyclidine ("PCP, angel dust") and water under concurrent fixed-ratio 16 schedules. One concentration was always held constant (0.25 ...
Rumbaugh D M - - 1987
In this research, we asked whether 2 chimpanzee (Pan troglodytes) subjects could reliably sum across pairs of quantities to select the greater total. Subjects were allowed to choose between two trays of chocolates. Each tray contained two food wells. To select the tray containing the greater number of chocolates, it ...
Corwin R L - - 1987
The effects of the anorectics benzphetamine, chlorphentermine, clortermine, mazindol, phendimetrazine, and phenmetrazine on food intake were compared to the effects of d-amphetamine in rhesus monkeys given daily access to food pellets. The ability of these compounds to maintain intravenous self-administration under a fixed-ratio 10 schedule was also determined in rhesus ...
Nakano Y - - 1986
Feeding-related neuronal activity of monkey amygdalar glucose-sensitive and morphine-sensitive cells was investigated during a task that required bar-pressing to obtain food. Both glucose-sensitive and morphine-sensitive cells, located mostly in the centromedial part of the amygdala, decreased firing during the bar-press period more often than insensitive cells. Naloxone attenuated the decrease ...
Wilpizeski C R - - 1986
Using squirrel monkeys as experimental subjects, we reexamined the disputed role of the area postrema (AP) in motion-induced vomiting. After anesthetization, the obex and rhomboid fossa were exposed surgically, and the AP was ablated by thermal coagulation using either a battery cautery or a CO2 microsurgical laser. Sham operations were ...
Ruiz de Elvira M C - - 1986
A backpack system is described whereby osmotic minipumps are used to infuse gonadotrophin-releasing hormone (GnRH) subcutaneously in a pulsatile manner into infertile socially subordinate female marmoset monkeys (Callithrix jacchus jacchus). This procedure enables long-term infusion of GnRH without the necessity of repeated subcutaneous implantation of pumps and GnRH reservoirs. The ...
Mue S - - 1986
The inhibitory effect of 3-isobutyryl-2-isopropylpyrazolo[1,5-alpha]pyridine (KC-404) on aerosolized methacholine- and histamine-induced increase in total respiratory resistance (Rrs) was determined in monkeys using the forced 3 Hz oscillation method and was compared with the effect of aminophylline. The effects of several derivatives of KC-404 on methacholine-induced bronchoconstriction were also determined. All ...
Feistner A T - - 1986
In order to explore whether or not adult motivation influences transfer of food to infants in cotton-top tamarins (Saguinus oedipus oedipus), 2 experiments were carried out with 3 large captive family groups. Examination of (a) natural changes in food motivation during feeding, and (b) elevated motivation toward food by giving ...
Hallonquist J D - - 1986
Electrical stimulation of the lateral hypothalamus in 2 species of hibernator, dormice (Glis glis) and ground squirrels (Spermophilus lateralis), suggests that induced behaviors may reflect activation of specific neural systems, rather than merely activation of a single central mechanism interacting with internal and external cues and past experience (prepotency hypothesis). ...
Beighton D - - 1986
The rate of growth of the predominant bacterial strains of plaque from the developmental grooves of first deciduous molar teeth was determined. Median doubling times were 3.32, 3.45, 2.88 and 4.54 h for streptococci, lactobacilli, actinomyces and Neisseria mucosa respectively. Withdrawal of dietary food did not greatly influence the number ...
D'Mello G D - - 1985
In marmosets, the clinical signs of poisoning following the administration of sarin and the effects of sarin upon performance in three behavioral test models were investigated. The sensitivity of marmosets to the lethal action of sarin was shown to be greater than that of rodent species and rabbits but very ...
van Wolfswinkel L - - 1985
The involvement of endogenous opioids in self-stimulation reward was investigated by repeated administration of the opioid antagonist naloxone to rats during acquisition of a behavioral response pattern that was rewarded with electrical (self-)stimulation of the ventral tegmental area. A control experiment was performed using food deprived rats in which a ...
Pager J - - 1985
The activity of 26 olfactory bulb units, including 19 mitral, 5 granular and 2 external plexiform cells, was recorded in unrestrained rats associating food odor stimuli/isoamyl acetate to a food reward/no reward. The respiratory activity was transduced from the intranasal air pressure and used as a time-base to analyze the ...
Killeen P R - - 1985
Incentive theory is successfully applied to data from experiments in which the amount of food reward is varied. This is accomplished by assuming that incentive value is a negatively accelerated function of reward duration. The interaction of the magnitude of a reward with its delay is confirmed, and the causes ...
Sasaki K - - 1984
In some medial forebrain bundle (MFB) sites, self-stimulation is often modulated by hunger or satiety. With electrodes in the nucleus accumbens (NAC) such modulation rarely occurs. The influence of food deprivation on MFB self-stimulation is the main basis for the hypothesis that electrical stimulation of the MFB can mimic the ...
Foltin R W - - 1984
Food intake of rhesus monkeys was limited to a single daily 2 hr session of banana flavored pellet availability, seven days a week. Following stabilization of intake, the effects of liquid preload meals (0-80% of normal meal size) delivered through nasogastric tubes or chronic indwelling intragastric (IG) catheters were determined ...
Veluvolu P - - 1984
Fecal samples of 36 ground squirrels, Spermophilus beldingi, from Tioga Pass (elev. ca. 3315 m) in the Sierra Nevada, California, yielded oocysts of Eimeria beckeri in nine squirrels, E. citelli in four squirrels, E. beldingii n. sp. in two squirrels, and degenerated, unidentifiable oocysts in ten squirrels. Eimeria beldingii n. ...
Lee V C - - 1984
Five adult male monkeys (Macaca mulatta) weighing 7.1-9.9 kg were given synthetic human beta-endorphin (800 micrograms) and [14C]methoxy-inulin (50 microCi) in 400 microliters of normal saline intrathecally. Serial samples of cerebrospinal fluid were drawn through a previously positioned indwelling spinal catheter and were assayed for concentrations of beta-endorphin (determined by ...
Carroll M E - - 1984
Orally-delivered methohexital was demonstrated to function as a reinforcer for rhesus monkeys with either phencyclidine or pentobarbital self-administration histories. The effects of food deprivation and food satiation were compared across a wide range of methohexital concentrations. Initially, three monkeys were trained to orally self-administer phencyclidine (0.25 mg/ml) and water, and ...
Kemnitz J W - - 1984
Food intake of control and streptozotocin-diabetic rhesus monkeys was measured during menstrual cycles and pregnancy. Intake of control monkeys was lower at the time of ovulation than during other phases of the menstrual cycle. Intake of control monkeys was also low during most of pregnancy, but this was accompanied by ...
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