Biochemical costs of a three day long cohabitation in dominant and submissive male Betta splendens

A 3 day long cohabitation in pairs of previously isolated adult male Betta splendens was studied. The first two mornings started with intense fighting, the frequency of which decreased during the day. The bursts of aggression noticed in the mornings were associated with a significant carbohydrate metabolism activation, while daytime activity resulted in a reduction of muscle proteins in the evenings. These changes were more pronounced in submissives than in dominants. The third day marked a shift in the behavior of the pairs: bursts of attack activity were not noticed, while the threatening display frequency increased. During this day a similar reduction in lipids was observed in dominants and submissives. While during the first 2 days the dominant position offered some metabolic advantage, this advantage disappeared during the third day when both members of the dyad seemed to do equally less well than their isolated counterparts. Combined with previous findings obtained in this series of experiments, the present results support the assumption that in this species the presence of one opponent is less well tolerated than the presence of four conspecifics. © 1994 Wiley-Liss, Inc.     

On the choice between eating and aggressive display in the Siamese fighting fish (Betta splendens)

In Expt 1, male Betta splendens were given a choice between food and a mirror image in a T-maze. All fish consistently preferred food. In Expt 2, the choice of fish that lived in the T-maze for the duration of the experiment was compared with the choice of fish that were transferred to the T-maze for each experimental session. Fish that lived in the T-maze consistently preferred food, but fish that were transferred showed a shift in preference toward mirror image. Differential inhibition of hunger and aggression by fear is suggested as the cause of the preference shift.     

Visual-reinforcer color-and operant behavior in Siamese fighting fish

Male Siamese Fighting Fish (Betta splendens) were conditioned to emit an operant response sequence reinforced by presentation of a model of a male Siamese Fighting Fish in aggressive display. Operant response rate varied as a function of the color of the model with respect to the color of the subject.     

Social-Cognitive and Behavioral Correlates of Aggression and Victimization in Boys' Play Groups

A contrived play group procedure was utilized to examine the behavioral and social-cognitive correlates of reactive aggression, proactive aggression, and victimization via peers. Eleven play groups, each of which consisted of six familiar African-American 8-year-old boys, met for 45-min sessions on five consecutive days. Social-cognitive interviews were conducted following the second and fourth sessions. Play group interactions were videotaped and examined by trained observers. High rates of proactive aggression were associated with positive outcome expectancies for aggression/assertion, frequent displays of assertive social behavior, and low rates of submissive behavior. Reactive aggression was associated with hostile attributional tendencies and frequent victimization by peers. Victimization was associated with submissive behavior, hostile attributional bias, reactive aggression, and negative outcome expectations for aggression/assertion. These results demonstrate that there is a theoretically coherent and empirically distinct set of correlates associated with each of the examined aggression subtypes, and with victimization by peers.     

Response acquisition by Siamese fighting fish (Betta splendens) with delayed visual reinforcement

Male Siamese fighting fish, Betta splendens, swam through a ring in an aquarium, breaking a photocell beam and initiating an unsignaled, resetting delay interval. Following delays of 0 s, 10 s, or 25 s, a 15-s mirror presentation released an aggressive display by the fish. Swimming through the ring increased in the absence of either a period of acclimatization to the reinforcer (analogous to magazine training when appetitive reinforcers are used) or explicit training of the response by the experimenters. Response rates were a decreasing function of delay duration. Other fish exposed to a schedule of response-independent mirror presentations failed to acquire and maintain the response. The results demonstrate the robustness and generality of the phenomenon of response acquisition with delayed reinforcement. They further qualify earlier observations about behavioral mechanisms involved in the phenomenon.     

The Italian version of the Social Comparison Rating Scale and the Submissive Behaviour Scale: Reliability and validity in a sample of adolescents

Social rank theory argues that social comparison and submissive behaviour are mechanisms by which humans and animals form themselves into social ranks. Design: this study assesses the psychometric properties of Italian versions of the Social Comparison Rating Scale—SCRS and Submissive Behaviour Scale—SBS in a sample of adolescents. The samples consisted of a clinical group (N = 200) and a non-clinical group (N = 1991). The non-clinical group allowed us to obtain two random samples used for the EFA and the CFA; moreover, we also extracted a Retest sample consisting of 219 subjects. Internal consistency was satisfactory and the factor structures were similar to the original version of the measures. The SBS and SCRS were significantly correlated with all the symptom profiles on the SCL-90-R, in both populations. Clinical populations had higher correlations with these measures. Statistical analyses showed a good fit to the data, replicating the constructs of the original scales. These results confirm that submissive behaviour and social comparison are associated with mental health problems.     

Perceptions of methylphenidate effects on hyperactive children's peer interactions

The behavioral constructs that emerge from observers' openended impressions of methylphenidate effects on the social behaviors of hyperactive children were examined. Ninety-six undergraduates observed videotapes of two different hyperactive target boys, each playing an interaction game with three peers. One target was taking methylphenidate and the other was taking placebo. The valence and content of observers' social perceptions were analyzed. Overall, more negative than positive behaviors were detected, a pattern more pronounced for the placebo than for the medication condition. Interestingly, placebo targets received negative evaluations for poorly controlled behaviors such as noncompliance, aggression, and disruption, but medicated targets received negative evaluations for social inhibition—passive and submissive behaviors. In contrast, the boys' medication state did not consistently influence observers' perceptions of positive social behaviors. Discussion focused on the extent and consequences of medicationrelated increases in social disengagement and on the ultimate impact of stimulant treatment on hyperactive children's social worlds.A preliminary report of this study was presented at the 1990 meeting of the Society for Research in Child and Adolescent Psychopathology, Costa Mesa, CA. We are grateful for the assistance of Pam Ajang, Keri Hom, and Scott Gutentag, and for support from the Fernald Child Study Center at UCLA.     

Influence of school-level and family-level variables on Chinese college students’ aggression

With the frequent occurrence of campus violence, scholars have devoted increasing attention to college students’ aggression. This study aims to estimate the prevalence of aggression in Chinese university students and identify factors that could influence their aggression. We can thus find methods to reduce the incidence of college students’ aggression in the future. A multi-stage stratified sampling procedure was used to select university students (N = 4565) aged 16–25 years in Harbin. The Aggression Questionnaire, the Adolescent Self-Rating Life Events Checklist and the Social Support Revalued Scale were used to collect data. Females reported lower levels of aggression than males (p < .001). A multiple linear regression analysis was conducted to determine the influence of factors of aggression, and the model was highly significant (R² = .233, Ad R² = .230, p < .01). The results show that the aggression is affected by gender, family-level and school-level variables. Aggression scores are significantly correlated with not only family-level or school-level variables independently, but their combination as well. We find that the risk factors for aggression include a dissatisfying profession, higher levels of study pressure, poor parental relationships, poor interpersonal relationships, the presence of siblings, punishment, health maladjustment, less subjective support, and lower levels of utilization of social support.     

Variation in aggressive behavior and anatomo-physiological correlates generated by crowding without physical contact in the house mouse

Behavioral, physiological (i.e., endocrine), and anatomical consequences of crowding in mice were studied in a situation where animals were in auditory, visual, olfactory, and tactile contact but restrained from full physical interactions, to prevent overt aggression. Males that cohabited with females undisturbed by neighboring conspecifics showed greater propensity to attack same-sex intruders and had higher plasma testosterone levels than did their “crowded” counterparts, that is, males cohabiting with females and housed adjacent to other male/female pairs. In this respect, the latter animals resembled submissive males. However, a significant increase in weight of androgen-dependent target organs (i.e., seminal vesicles and preputial glands) was found in crowded males. These data indicate that despite the observed inhibition of social aggression these males are not physiologically comparable (homologous) to male mice that experienced defeat and the stress of submission during fighting. The intriguing possibility that different conversion pathway of testosterone are accelerated, as a result of social communication, in males living in these two environments and the behavioral implications of these possibilities are discussed. Finally, the parental behavior of crowded animals, although not freely interacting with each other, was disrupted, causing a marked decrease in reproductive success. In this situation a high incidence of infanticide of their offspring by both parents was observed, whereas this behavior was virtually absent in non-crowded male/female pairs.     

Illuminating the nomological network of digital aggression: Results from two studies

We examined the nomological network surrounding digital aggression (DA), in regards to other forms of aggression/antisocial behavior and individual difference variables commonly associated with other forms of aggression/antisocial behavior. Two large samples of university students (N = 713 and 633, respectively) completed a series of questionnaires and in some cases, an additional experience sampling study. Results revealed that, in emerging adulthood, DA appears to have a unique demographic profile relative to the other forms of aggression and antisocial behavior. Results further suggested that, when examined simultaneously, only social aggression and non‐aggressive rule‐breaking evidenced independent associations with DA. These associations persisted even in the absence of social media use. Unique associations with most individual difference variables dissipated once we controlled for social aggression and rule‐breaking, although DA was independently associated with extraversion and alcohol use problems. Such findings begin to embed DA in its broader nomological network and suggest clear functional links with both social aggression and non‐aggressive rule‐breaking.

     

The role of empathy and social anxiety in Latinx adolescents' indirect peer aggression during the transition to high school

The primary purpose of this study was to evaluate the relationship between decreased empathy (i.e., cognitive and affective) and indirect and cyber peer aggression among Latinx adolescents during their transition to high school. Further, we examined the degree to which social anxiety moderated this relationship. Participants were 469 Latinx ninth graders, ages 13–17 years (M = 14.52, SD = 0.58; 58% girls). Adolescents completed the Revised Peer Experiences Questionnaire, Cyber Peer Experiences Questionnaire, Basic Empathy Scale, and Social Anxiety Scale for Adolescents at two different time points, 3 months apart. Hierarchical linear regression analyses revealed concurrent and prospective relationships between lower cognitive empathy and the perpetration of both indirect and cyber aggression. In addition, social anxiety moderated the concurrent associations between both types of empathy and both types of aggression perpetration. Results suggest that interventions that facilitate cognitive empathy and decrease social anxiety may help to reduce adolescents' indirect and cyber aggression toward peers throughout the high school transition.     

High maternal aggression in dwarf hamsters (Phodopus campbelli and P. sungorus)

The defense of offspring, termed maternal aggression, is a highly conserved behavior in mammals, including rodents. This study examined relative levels of maternal aggression in two closely related dwarf hamster species, Phodopus campbelli and P. sungorus, that normally inhabit high latitude, boreal environments. When tested with first litters and with the breeder male remaining with the female (for P. campbelli the male is necessary for successful rearing of offspring), both species exhibited high levels of maternal aggression with average duration of aggressive behavior>80 sec for a 10 min test. For P. sungorus, males are not required to rear offspring. P. sungorus females with either one or multiple litters (singly housed after impregnation) exhibited significantly higher levels of aggression (>300 sec) relative to females co‐housed with the sires. In terms of species differences in attack style, P. campbelli exhibited a boxing or clawing strategy for ～50% of total attack time, but for P. sungorus, this form of attack occurred<5% of the time. For P. sungorus, attacks to the vulnerable belly and flank constituted>90% of all attacks, but these regions were attacked ～50% of the time for P. campbelli. A survey of levels of maternal aggression of rodents in other genera suggests that maternal aggression in Phodopus is at the high end of the spectrum. Results of this study suggest that the presence of the breeder male may actually suppress aggression in P. sungorus. This fact, as well as its high level of aggression and its distant relationship to mice and rats, suggest P. sungorus as a possible model for future studies on the neurobiological basis of maternal aggression. The relationship between the high rates of maternal aggression and life history strategy in Phodopus is discussed. Aggr. Behav. 00:000–000, 2005. © 2005 Wiley‐Liss, Inc.     

Manipulations of vasopressin alter aggression differently across testing conditions in monogamous and non‐monogamous Peromyscus mice

Differences in the distribution of arginine vasopressin (AVP) and a subtype of AVP receptors, the V_1a receptor, may explain dissimilarities in social behavior of monogamous and non‐monogamous rodents. Intracerebroventricular infusions of AVP and a V_1a antagonist were used in sexually naive males of two mouse species, the monogamous and highly aggressive California mouse (Peromyscus californicus) and the non‐monogamous and less aggressive white‐footed mouse (P. leucopus), to begin testing the interaction between the social system of a species and the effects of AVP on aggression. Two testing conditions, the resident‐intruder aggression test (R‐I) and the neutral arena aggression test, were used because they may differ in function and underlying biological mechanisms. In the R‐I test, administration of the antagonist lengthened attack latencies in California mice. In contrast, blocking V_1a receptors did not alter attack latencies in the R‐I test in white‐footed mice or in the neutral arena aggression test in both species. AVP also did not alter aggression in either species in either behavioral test. Overall, these results suggest that AVP may be more likely to be associated with offensive aggression as measured in the R‐I test than with neutral arena aggression and that the effects of AVP manipulations may differ between monogamous and non‐monogamous rodents. Aggress. Behav. 31:000–000, 2005. © 2005 Wiley‐Liss, Inc.     

Influence of dominance on the development of play fighting in pairs of male Syrian golden hamsters (Mesocricetus auratus)

In the highly social rat, male juvenile and adult subordinates initiate more playful contacts with dominant pairmates than vice versa. This study examined the effect of dominance on playful contacts in the relatively asocial golden hamster. Pairs of male hamsters were reared together from weaning, and their play was filmed in the juvenile (28-36 days) and the young adult (60-70 days) stages of development. By the adult stage, it became clear that one pairmate was dominant over the other. The dominant pairmate launched all aggressive attacks (i. e., bites to the lower flanks and rump), and the subordinate pairmate performed all the submissive gesturing (e. g., tail up submissive posture). Playful contact, which in this species involves gentle nibbling of the posterior cheeks, was more frequently launched by the dominant than by the subordinate. This was not only true at the adult stage, but also at the juvenile stage, before dominance-subordination relationships were sharply polarized. Therefore, it would appear that in the relatively asocial hamster, the subordinates tend to avoid playful contact with dominants. This is markedly different to rats, where the subordinates actively seek out and engage dominants in play. This contrast further supports our hypothesis that subordinate male rats use play as a means of maintaining familiarity with dominants. © 1993 Wiley-Liss, Inc.     

The influence of an audience upon the reactions to filmed violence

In order to examine audience effects when viewing firmed violence, 5 to 6 year old pre-school boys who had been rated as submissive by their teachers watched an aggressive or a neutral movie either alone, accompanied by another submissive classmate, or a dominant one. Subsequent aggression against a frustrating, unknown and unseen boy was delivered via a modified Buss machine, especially adapted for children. Subjects accompanied by a dominant peer were more aggressive than the others but did not react differentially to the movies. Subjects tested alone were more aggressive after the violent film than after the neutral one and the opposite pattern occurred for the boys accompanied by a submissive classmate. These findings stress the importance of the social context when viewing filmed violence. It is suggested that the quality of the audience can have different directional (e.g. fear and aggression) as well as energizing properties. Links with the literature on social facilitation and audience effects are underlined.     

Obedience to authorities is not unconditional: Differential effects of COVID-19 threat on three facets of RWA in Poland and Germany

Collective authoritarian responses to threat might differ depending on whether people trust collective authorities in reducing threat. Thus, we tested the differential effects of epidemic threat on three facets of right-wing authoritarianism, in Germany (a country with high authorities' efficacy in responses to COVID-19) and Poland (low authorities' efficacy context). Two representative sample longitudinal studies performed in Poland (N = 892) and Germany (N = 883) showed that in Germany feelings of COVID-19 threat explained increases in authoritarian submission and (to a lesser extent) authoritarian aggression, whereas in Poland such feelings of threat explained changes in authoritarian aggression and conventionalism after the pandemic, but did not alter authoritarian submission. These findings suggest that specific authoritarian reactions to threat (submissive vs. conventionalist) might depend on the general trust in authorities' ability to respond to crises.     

Maternal aggression as a model for acute social stress in the rat: A behavioral-electrocardiographic study

Maternal aggression of lactating rats was used to induce acute social stress in a resident-intruder paradigm. Behavioral and electrocardiographic responses of male intruders were simultaneously recorded. Cardiac electrical activity was measured by means of a telemetry system which ensured preservation of intruder's behavioral repertoire. Behavioral response to maternal attack was evaluated in terms of percent time spent in passive/submissive (p/s) and active/non-submissive (a/ns) patterns. This allowed us to classify the intruders as submissive, non-submissive, and intermediates. During the test, a significant decrease of average R-R interval (R-R) compared to baseline conditions and the occurrence of arrythmias of different nature were found. Ventricular arrhythmias, including premature ventricular beats and ventricular tachycardias, were present in all the intruders while R-R fluctuations and II degree atrioventricular (A-V) blocks only appeared in submissive and intermediate rats. Most ventricular arrhythmias occurred within the upper range of heart rate and were preceded by periods of low R-R variability. These electrocardiographic events were temporally associated with a/ns behavioral patterns and were related to an increased prevalence of sympathetic activity. On the other hand, R-R fluctuations and II degree A-V blocks preceded by high R-R variability were synchronized with p/s behavior and were ascribed to a predominant inhibitory effect of vagal activation which becomes more pronounced as the level of sympathetic activity increases. © 1995 Wiley-Liss, Inc.     

Male versus female Siamese fighting fish as reinforcing stimuli for conspecific males in single- and two-choice operant situations

Two experiments attempted to determine the reinforcing effectiveness of visual exposure to a female versus a male stimulus in male Siamese fighting fish (Betta splendens). This was accomplished by making male or female presentation contingent upon an operant ring swimming response in single- (Experiment 1) and two-choice (Experiment 2) continuous reinforcement operant situations for 1 hr per day. It was found that visual exposure to a female stimulus was behaviorally reinforcing in a way comparable to that typically found in intermale studies. If given a choice, male test subjects were observed to demonstrate a consistent preference for the female as opposed to the male stimulus. The results are discussed in terms of stimulus discrimination and approach-avoidance conflict as differentially elicited by male and female target stimuli.     

Sex differences in social representations of aggression: Men justify,women excuse?

Women tend to hold an expressive social representation of aggression (as a loss of self‐control) while men tend to hold an instrumental representation (as a means of imposing control over others). Because expressive beliefs correspond to excuses and instrumental beliefs to justifications, it may be a sex difference in moral acceptability of aggression that informs social representation. Participants completed the Expagg questionnaire with reference to an episode of same‐sex or cross‐sex physical aggression and rated the moral acceptability of their behaviour. Women scored higher on Expagg (specifically lower than men on the instrumental scale) but there was no effect of target sex or participant‐by‐target interaction. Contrary to expectation, women rated their own aggression as more acceptable than did men and hence this could not explain their lower levels of instrumentality relative to men. Aggr. Behav. 29:128–133, 2003. © 2003 Wiley‐Liss, Inc.     

Intra- and lnterspecific aggression in two species of field crickets,Gryllus integer and G. alogus

Adult, laboratory-reared, and singly caged field crickets, Gryllus integer, of known ages and representing F1 to F4 generations, were exposed to 15–20-minute bouts of social interaction with introduced adult intruder males on alternate days from approximately 1 week after adult molt to time of death. A total of 3,523 paired-male bouts for 116 male G. integer were recorded over a 2.5-year study period. Adult males used as intruders were wild-caught or laboratory reared G. integer, but for nine of the 116 experimental males, wild-caught intruders of a closely related sympathetic species, G. alogus, were used for all or many of the bouts. Bouts between male G. integer and conspecific intruders were characterized by significantly elevated levels of aggression (t=6.04, P<0.001) compared with males exposed to heterospecific G. alogus intruders in interspecific interactions. Significant differences (p<0.005, chi-squared test of independence) existed at four out of five levels in a hierarchy of agonistic behaviors. Most G. integer males exposed to both G. integer and G. alogus intruders showed significantly reduced aggression levels during the interspecific interactions (p<0.001, Mann-Whitney U test). Conspecific G. integer dyads in the intraspecific interactions showed significantly stable dominant-subordinate relationships over time. Confusion surrounding the use of the term aggression is described with reference to Arthropods in general and Orthopteran insects in particular, and some likely proximate and ultimate bases for reduced interspecific aggression in field crickets are discussed.