Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Competitive Behavior”

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 73 records · Page 4Linked to original sources
PubMedDate not supplied

Correlating testosterone and fighting in male participants in judo contests.

The role of hormones in human aggression is open to debate, but takes on a new urgency owing to the alarming abuse of androgenic anabolic steroids by some sports participants. In this study, video-taped behavior exhibited by 28 male competitors during a judo fight was assessed to analyze its relation to serum testosterone and cortisol levels measured before and after the bouts. A positive relation between testosterone and offensive behaviors was obtained in the sense that the greater the hormonal titer, the greater the number of threats, fights, and attacks. These findings coincide with the pattern of relationships found using observational scales. Conversely, cortisol also presented positive correlations with some of these behavioral categories but did not moderate the relationship between testosterone and competitive behavior. The present results corroborate and extend earlier findings on the role of these hormones in human behavior, giving support to the view that testosterone can be linked to the expression of competitive aggression.

Adolescent↗
PubMed1987

The effects of d-amphetamine on food competition in male rats.

Male Wistar rats were tested in 3 competitive situations to determine the effects of d-amphetamine (AMP) on competitive behavior. Subjects were initially tested in a fixed-pair food competition paradigm. Based on the percentage of pellets obtained, a winner and loser were defined for each pair. AMP (2.0 and 4.0 mg/kg) was then administered to one or both members of pair, and the effects of the drug on the defined winners and losers were determined. AMP did not significantly alter the percentage of pellets obtained by losers except when only the winners were administered AMP (4.0 mg/kg). Subjects were then tested in a round-robin competition paradigm in which each subject was paired with every other subject. The animals were ranked according to the percentage of pellets obtained out of a possible 450 pellets. AMP (2.0 mg/kg) decreased pellet acquisition in higher ranking subjects, whereas pellet acquisition was increased in lower ranking subjects. The effects of AMP were also evaluated in a "worker-parasite" paradigm. Subjects were individually conditioned to press a lever using an FI schedule for presentation of a food pellet. When the lever was located on the wall opposite the food hopper, a worker and parasite were defined for each pair. The worker was the subject that made the most responses on the lever while obtaining fewer reinforcements. Subjects that were defined as winners in the fixed pair food competition emerged as the workers in this situation. AMP (0.8 mg/kg) given concurrently to both subjects resulted in a reversal of roles; the parasites now emitted the majority of responses and obtained less pellets. The data indicate that AMP has a differential effect on participants in competitive situations when all subjects in the situation are treated.

Animals↗
PubMed1998

Gender and Negotiator Competitiveness: A Meta-analysis.

Although there have been numerous investigations into the relationship between gender and bargaining competitiveness over the past several decades, few conclusions have been reached. The results of 62 research reports on the relationship between gender and competitive behavior in dyadic bargaining interactions were examined by meta-analytic review. The average weighted effect size indicated that women appear to behave more cooperatively in negotiations than men, but this difference is slight. Results suggest that constraints on negotiators (imposed by abstract bargaining paradigms and restrictions on communication) lessen gender differences in negotiation behavior. Women were significantly more competitive than men when competing against an opponent who pursued a "tit-for-tat" bargaining strategy. Copyright 1998 Academic Press.

Journal Article↗
PubMed1996

Ultrafast glycerophospholipid-selective transbilayer motion mediated by a protein in the endoplasmic reticulum membrane.

A relatively rapid transbilayer motion of phospholipids in the microsomal membrane seems to be required due to their asymmetric synthesis in the cytoplasmic leaflet. Marked discrepancies exist with regard to the rate and specificity of this flip-flop process. To reinvestigate this problem, we have used both spin-labeled and radioactively labeled long chain phospholipids with a new fast translocation assay. Identical results were obtained with both types of probes. Transbilayer motion of glycerophospholipids was found to be much more rapid than previously reported (half-time less than 25 s) and to occur identically for phosphatidylcholine, phosphatidylserine, and phosphatidylethanolamine. Such transport is nonvectorial and leads to a symmetric transbilayer distribution of phospholipids. In contrast, transverse diffusion of sphingomyelin was 1 order of magnitude slower. Phospholipid flip-flop appears to occur by a protein-mediated transport process displaying saturable and competitive behavior. Proteolysis, chemical modification, and competition experiments suggest that this transport process may be related to that previously described in the endoplasmic reticulum for short-chain phosphatidylcholine (Bishop, W. R., and Bell, R. M. (1985) Cell 42, 51-60). The relationship between phospholipid flip-flop and nonbilayer structures occurring in the endoplasmic reticulum was also investigated by 31P-NMR. Several conditions were found under which the 31P isotropic NMR signal previously attributed to nonbilayer structures is decreased or abolished, whereas transbilayer diffusion is unaffected, suggesting that the flip-flop process is independent of such structures. It is concluded that flip-flop in the endoplasmic reticulum is mediated by a bidirectional protein transporter with a high efficiency for glycerophospholipids and a low efficiency for sphingomyelin. In vivo, the activity of this transporter would be able to redistribute all changes in phospholipid composition due to biosynthetic processes between the two leaflets of the endoplasmic reticulum membranes within a time scale of seconds.

Animals↗
PubMedDate not supplied

Agonistic behavior: a model, experimental studies, and perspectives.

Agonistic (competitive) behavior includes the manifestations of aggression and submissiveness by individuals in conflict situations and is a universal form of behavior found in animals of different species. The sensory contact model allows aggressive and submissive (inhibited, suppressed) types of behavior to be formed in male mice as a result of acquisition of repeated experience of social conquests or defeats in daily aggressive interactions. Chronic experience of aggression is accompanied by total activation of the dopaminergic systems in the victors. At the same time, experience of social defeat leads to changes in the state of the serotoninergic and noradrenergic systems of various parts of the brains of the defeated animals. As a consequence, significant differences in emotional expression, movement activity, investigative activity, communicative ability, alcohol consumption, and many physiological aspects were found in animals of opposite social groups. The extent and nature of these changes depended on the type of social behavior formed by the animals (victors, vanquished), the duration of confrontational experience, and the genetically determined characteristics of the animals (i.e., which line of mice). The possibilities and perspectives of this model of sensory contact in medical-biological and basic investigations is discussed.

Agonistic Behavior↗
PubMed1988

Competition for sucrose-pellets in triads of male Wistar rats: effects of three serotonergic drugs.

1. Within triads of rats, individuals can be discerned according to their competition for sucrose-pellets as a high-, a medium- and a poor-performing animal. 2. The competition-rates, expressed as scores, are affected by serotonergic drugs: upon inhibiting tryptophan-hydroxylase, the characteristic abstention of the poor-performing rats can temporarily be overcome; quipazine, on the other hand, leads to a dose-dependent decrease in the competition-rate of high-performing rats. 3. Such findings are indicative for a regulatory effect of some serotonergic mechanisms on a competition-behavior evoked within the familiar social context.

Animals↗
PubMed1984

Personality and self-motivation during biochemical fatigue.

The present study was conducted to determine whether females exhibiting the Type A behavior pattern would exert greater effort and work to higher levels of physiological fatigue in a self-motivated ergometer test. Twenty female subjects, half of them Type A and the other half Type B, were administered an incremental ergometer test to determine their peak oxygen consumption value. On the first experimental session no experimenter encouragement was given to the subjects. Consequently the test measured physical motivation levels. During a second laboratory session, each subject was continuously encouraged by the experimenter to maintain exercising until she was truly incapable of further work. The highest rate of oxygen extraction during this latter session was considered the subject's maximum oxygen consumption (i.e., VO2 max). Type A and B subjects were compared in the nonmotivated testing session (experimental session 1) to their "true" individual capacities (maximum oxygen consumption demonstrated in experimental session 2). ANOVAs indicated no significant differences in self-initiated competitive behavior during a physical stressor.

Adult↗
PubMed2005

The competitive nature of cells.

The possibility that cells of multicellular organisms may compete with one another has been postulated several times. It was experimentally confirmed in Drosophila, probably for the first time, when cells with different metabolic rates were mixed: cells that would have been viable on their own disappeared due to the presence of metabolically more active cells. After almost 30 years of neglect, genetic analysis in Drosophila has started to reveal a gene network that regulates the competitive behavior of cells. If the genes regulating cellular competitiveness in Drosophila have a conserved function in mammals, the study of cell competition could have an impact in several biomedical fields, including functional degeneration, cancer, or stem cell therapies.

Animals↗
PubMed2004

Maternal separation alters maternal care, but has minor effects on behavior and brain opioid peptides in adult offspring.

The aim of the study was to investigate the effect of repeated maternal separation (MS; 4 hr per day) during postnatal Days 1 to 15 on emotionality and voluntary ethanol intake in adult male and female Wistar rat offspring relative to controls exposed to a brief (5-min) daily handling procedure. Brain immunoreactive opioid peptide levels and plasma levels of corticosterone also were measured. There were mainly no alterations in any of the tested behaviors (i.e., fleeing and freezing responses, exploratory behavior, spontaneous and amphetamine-induced locomotor activity and competitive behavior), ethanol intake, or immunoreactive opioid peptide levels in MS offspring, either in males or females, compared to their respective controls nor were there any differences in plasma corticosterone between groups. In addition, the dams' retrieval behavior of the pups also was studied, showing that MS dams spent more time in the nest with the pups after the 4-hr separation period compared to control dams. With respect to the used protocol of the MS procedure in the present study, our results do not provide support for the suggestion that this procedure is a relevant model for studying development of psychopathology and vulnerability to drug abuse.

Animals↗
PubMed1994

Competitive adsorption of alpha-lactalbumin and bovine serum albumin to a sulfopropyl ion-exchange membrane.

Breakthrough curves were measured for pure solutions of alpha-lactalbumin (ALA) and bovine serum albumin (BSA) individually, and for a binary mixture of the proteins, using a sulfopropyl ion-exchange membrane. The breakthrough curves were qualitatively consistent with local-equilibrium theory predictions. Competitive adsorption caused displacement of bound BSA monomer by the more strongly binding BSA dimer, illustrating that even apparently single-protein systems may display multicomponent competitive behavior. In the two-protein experiment, ALA was competitively displaced by the more strongly binding BSA monomer and dimer, indicating that the binding strength was in the order: BSA dimer > BSA monomer > ALA.

Adsorption↗
PubMed1988

An economic analysis of the nurse practitioner role.

Today's rapidly changing health care environment directly affects nurse practitioners. NPs will be practicing in increasingly competitive situations and with mounting pressures for cost-effective services. Ignoring the issues in the health care marketplace can threaten NP survival. This article will analyze the changes in the health care system, relate the economic effects of these changes to nursing practice, and apply a homeostatic model of interprofessional competitive behavior. As NPs gain perspective on the dynamics of competition and the influence of economics, they will be better able to successfully position themselves in the health care marketplace.

Economic Competition↗
PubMedDate not supplied

A research note on body mass, physical aggression, and the competitiveness of Asian-Pacific Islander adolescents in Guam.

This study uses the evolutionary model to guide an exploration of the effects of body mass on aggressive and competitive behaviors among Asian-Pacific adolescents in Guam. Using a probability sample of Guam's high-school students, the results of logistic regressions suggest that adolescent females with greater body mass are more likely to engage in physical fights (aggression) and to participate in team sports (competitiveness). Ethnic differences indicate the possibility that individuals with lower body mass may be less likely to participate in physically aggressive acts and team sports. Alternate theoretical explanations for the results are also considered.

Adolescent↗
PubMed1996

The prevalence of self-reported problems in young adults from the general population.

This study assessed the prevalence of a wide range of behavioral and emotional problems in 706 19- to 24-year-olds from the Dutch general population using the Young Adult Self-Report (YASR). The prevalence rates found can be used to make comparisons with data from individuals or other samples. Large or medium (variance > 5.9%) sex effects were found for alcohol use, for the items 'Brags' and 'Swears' (males > females), and for the items 'Cries a lot' and 'Fears' (females > males). With respect to socially desirable items, females more often reported attitudes or behaviors pertaining to helping other people, while males more often reported competitive behaviors or attitudes. For YASR syndromes, higher mean scores for females than males were found for the Withdrawn, Somatic Complaints, and Anxious/Depressed syndromes, while mean scores on the Delinquent Behavior syndrome were higher for males than females. No age effects were found, indicating that normative data were similar across the 19- to 24-year age span. Compared to other problem areas, thought problems and delinquent behavior in males, and social problems and delinquent behavior in females were least likely to be associated with other types of problems. Hence, instruments for the assessment of psychopathology in young adults should include these areas to provide a comprehensive picture of behavioral and emotional problems.

Adult↗
PubMed1987

Performance and physiological responses of type A and type B individuals during a cognitive and perceptual-motor task.

A total of 36 male individuals, 18 classified as Type A and 18 as Type B performed a cognitive (tonal memory) and a perceptual-motor (simulated race car driving) task along with a secondary reaction time (RT) task. Heart rate (HR), skin temperature, and skin conductance (SC) were measured. Multiple linear regression analysis revealed that tracking was related to Jenkins Activity Survey indicating superior performance for those scoring high in overall Type A behavior and low in the H sub-scale (hard driving, competitive behavior). Persons scoring high in the S scale (speed and impatience) and low in the H scale performed better in the short-term memory task. Type A subjects had higher HR and performed better (faster RTs and higher scores) than Type Bs, but only while engaged in the cognitive task. The Type As also had higher SCs than Bs, although they were not differentiated according to task. Sub-scale patterns may have important implications for refining the Type A behavior concept.

Adolescent↗