Physical aggression: Effects of ethnicity of target and directionality of aggression

Physical aggression of members of a powerful majority ethnic group against an opponent either from a powerless and discriminated against minority or from their own group was tested as a function of aggression directionality and aggressor's attitudes. It was hypothesized that under bidirectional aggression where the opponent could aggress as well, members of the powerful majority group would adjust their aggressive responses to that of their opponent's regardless of his ethnic origin and regardless of aggressor's attitudes. However. under unidirectional aggression where the opponent was powerless, it was expected that those subjects who held unfavourable attitudes toward members of the minority group would be more aggressive against an opponent of that group than against an opponent of his own ethnic group. Subjects who had neutral attitudes would be equally aggressive toward all opponents. Ninety-six 11th grade vocational high school male students of Western origin, were given the opportunity to administer electric shocks to an opponent who was either of Western or Oriental origin in a competitive situation, Subjects were selected according to their attitudes toward Oriental Jews. Half expressed negative attitudes, the other half neutral attitudes. Half of the subjects expected their opponent to reciprocate shocks, the others did not. Contrary to expectations it was found that the attitudes of subjects of Western origin towards Orientals did not effect their aggressive behaviour. When aggression could not be reciprocated, all subjects were more aggressive toward an opponent of Oriental than of Western origin. The findings showed that when aggression was bidirectional, all subjects adjusted their aggressive behaviour, to their opponents'. However, they were less aggressive towards an opponent of Oriental than of Western origin.     

The consequences of noncooperation for the target of third party instigated aggression

Consequences for a new target as a function of noncooperation was investigated in the instigative aggression paradigm. Subjects instigated partners to aggress against an opponent by suggesting what shock intensity to deliver. The partner was either cooperative (i.e., complied with the suggestion) or noncooperative (i.e., refused to set high shocks). Subsequently, subjects were given the opportunity to be directly aggressive by actually setting the shocks themselves. During this phase a new target who was nonprovocative was introduced. Subjects aggressed alone, in the presence of their partner, or in the presence of a new person. Results revealed that noncooperation reduced the level of instigative aggression and carried over to the second phase of the experiment. Subjects who had had cooperative partners were more aggressive toward the new target than were subjects who had had noncooperative partners. The presence or absence of the partner was not significant.     

Withdrawal,matching, withdrawal-matching,and variable-matching strategies in reducing attack-instigated aggression

Several studies have investigated strategies that a participant in dyadic aggression may use to reduce the aggression of the other participant. In one set of these studies the subject is instigated to aggression by an opponent who sets maximum shocks for the subject to receive during the first block of six trials. Following attack-instigation, opponents shift to withdrawal and matching strategies for 18 trials. The withdrawal strategy is an abrupt shift to the lowest levels of shock possible. The matching strategy is the exact matching by an opponent of the shock set by the subject on the previous trial. With these procedures the withdrawal strategy has been the most effective method to reduce aggression. These results led to the suggestion that the effectiveness of the withdrawal strategy may be due to immediate, unambiguous communication by the opponent of his willingness to reduce attack. This hypothesis was tested in the present study by creating a matching condition modified to include immediate, unambiguous communication of willingness to reduce attack. In this withdrawal-matching condition the opponent followed attack with two trials of the lowest levels of shock before shifting to a matching strategy. Although the withdrawal-matching strategy did not lead to shock settings that were significantly lower than the matching strategy, there was evidence that subjects interacting with withdrawal-matching opponents did reduce their shock settings from block 1 to block 4 more rapidly than subjects interacting with matching opponents. A variable matching strategy was also used to provide a more realistic analogy of matching in the mundane world. While subjects with variable-matching opponents also did not set shock levels during blocks 2, 3, and 4 that were significantly lower than the matching strategy, there was evidence that subjects in this condition reduced their shock levels more rapidly than subjects with matching opponents. Although the effects were not as strong as expected, the results do provide some support for the interpretation that the effectiveness of the withdrawal strategy may be due to unambiguous communication of willingness by the opponent to reduce his or her aggression. The effectiveness of the variable-matching strategy was attributed to interrupting the tendency of the subject and his or her opponent to match each other's responses. Consistent with earlier attack-instigated aggression studies, the withdrawal strategy in the present study led to a rapid reduction in aggression.     

Knowing your audience affects male–male interactions in Siamese fighting fish (Betta splendens)

Aggressive interactions between animals often occur in the presence of third parties. By observing aggressive signalling interactions, bystanders may eavesdrop and gain relevant information about conspecifics without the costs of interacting. On the other hand, interactants may also adjust their behaviour when an audience is present. This study aimed to test how knowledge about fighting ability of an audience affects aggressive interactions in male Siamese fighting fish. Subjects were positioned between two dyads of non-interacting males and allowed to observe both dyads shortly before the view to one of the dyads was blocked, and the dyads were allowed to interact. Subjects were subsequently exposed to an unknown opponent in the presence of either the winner or the loser of the seen or unseen interaction. The results suggest a complex role of the characteristic of an audience in the agonistic behaviours of a subject engaged in an interaction. The presence of a seen audience elicited more aggressive displays towards the opponent if the audience was a loser. This response was different in the presence of an unseen audience. Subjects then directed a higher aggressiveness against their opponent if the audience was a winner. These results also suggest a potentially more complex and interesting process allowing individuals to gain information about the quality and threat level of an unknown audience while it is interacting with a third party. The importance of information acquisition for an individual to adapt its behaviour and the role of communication networks in shaping social interactions are discussed.     

The effects of alcohol and persuasive social pressure on human physical aggression

Intoxicated and nonintoxicated subjects were given the opportunity to administer electric shocks to a nonprovocative opponent within the context of a competitive reaction time task. Social pressure was used to persuade subjects to administer a highly noxious electric shock to the passive opponent. The social pressure manipulation significantly increased the intoxicated subjects' use of the highly noxious shock. Non-intoxicated subjects did not evidence an appreciable increase in the use of the intense shock option.     

Third party instigation of aggression as a function of attack and vulnerability

Subjects serving as advisors instructed a confederate which shock intensity to deliver to an opponent in a reaction-time competition; subjects could also directly aggress by setting shock for the opponent's partner. Vulnerable subjects (shock electrode on) both instigated less aggression, i.e., suggested that less intense shocks be set, and directly aggressed less frequently than nonvulnerable subjects (no shock electrode). Attacked subjects, those for whom the opponents set shock, both instigated more aggression and more frequently set shock than did nonattacked subjects. The relationship between vulnerability and attack was additive for instigative aggression and multiplicative for direct aggression. Both modes of aggression were significantly influenced by the intensity of provocation from the opponents.     

Instigation to aggression as a function of degree of defeat and the capacity for massive retaliation

Forty-eight subjects, half of whom were assigned to a condition of massive retaliation (MR) and half of whom were not (NMR), competed against a presumed opponent The loser on each trial received a shock of intensity level selected by the winner at the beginning of a trial and, simultaneously, feedback on the opponent's shock setting The winner received only feedback on the opponent's shock setting Defeat and feedback of aggressive intent (opponent's shock setting) were varied independently In the MR condition, an extreme level of shock could be selected Although its use was avoided, its psychological presence influenced perception of the opponent, aggressive behavior, and physiological arousal Consistent with previous findings, primary frustration was found to be a relatively inconsequential instigator to aggression compared to learned social attitudes     

Self-Consciousness,Self-presentation,and Performance Under Pressure: Who Chokes,and When?

Choking under pressure by persons low and high in self-consciousness was examined as a function of two sources of performance pressure: audience and performance feedback. Subjects competed with an alleged opponent on a psychomotor task while alone, before a supportive (same team) audience, or a nonsupportive (opposing team) audience. Before the critical trial, subjects learned that their team was either somewhat ahead of or somewhat behind the opposing team. Self-consciousness, audience, and feedback interacted to affect performance during the critical trial. When disappointing the audience was likely, subjects low in self-consciousness choked. Subjects high in self-consciousness tended to choke when they were told that their team had fallen behind. It is suggested that persons who are low and high in self-consciousness experience different types of performance pressure due to disparate self-presentational motives.     

Beating lady luck: Effects of competitive gambling on opponent likeability and targeted physical aggression

This study aimed to examine the effects of gambling motives and competitive gambling outcomes on opponent likeability and targeted physical aggression. We hypothesized that (a) losers would perceive their opponents to be less likeable and (b) would be physically more aggressive toward their opponents. Opponent likeability was proposed to mediate the lose–aggression relationship while social gambling motives were proposed to moderate the lose–aggression relationship. Specifically, we expected that losers of competitive gambling situations would engage in greater physical aggression only if they perceived their opponents to be less likeable. In addition, lower perceived opponent likeability would translate into greater targeted physical aggression only if the loser possessed low social motives for gambling. Ninety‐eight undergraduates who self‐identified mostly as recreational gamblers participated in a competitive gambling game. The Hot Sauce Paradigm was adapted as a measure of targeted physical aggression. Results obtained supported our hypotheses. Potential implications and limitations are discussed.     

Interpersonal aggression as a function of subject's sex, subject's sex role identification, opponent's sex, and degree of provocation.

Ninety-five undergraduates served as subjects in an experiment where they could administer electric shock to an opponent and receive the same from an opponent. The independent variables were subject's sex, subject's sex role identification (as measured by the Bem Sex Role Inventory), opponent's sex, as well as degree of provocation from the opponent. Aggression was defined as level of shock chosen by the subject for the opponent. The results indicated that masculine subjects facing a male opponent were more aggressive than individuals of other sex role identifications whether or not they were provoked. It was also found that masculine males were more aggressive than other males or anyof the females. Furthermore, opponent's sex influenced the males' aggressiveness but had no effect on the degree of aggression in females. Finally, aggression increased in all subjects following increases in provocation. The results are discussed in terms of their implications for pyschological androgyny.     

Effects of racial prejudice and race of target on aggression

Three studies were conducted to investigate the relationship between prejudice and physical aggression using the competitive reaction time paradigm. In Study 1, high and low prejudiced subjects competed against either a black or white opponent. The race of the opponent did not differentially affect the aggressive behavior of either high or low prejudiced subjects. In Study 2, high prejudiced subjects were confronted with a competitor who behaved in a nonaggressive fashion. Under these conditions, the high prejudiced subjects attacked the black target more than the white target. In Study 3, high prejudiced subjects competed against an opponent who communicated nonaggressive intentions. The subjects behaved in a nonaggressive manner toward both the black and the white target. It was proposed that prejudice facilitates indiscriminate aggression in the presence of a clear threat and selective aggression in the presence of ambiguous threat.     

Witnessed aggression: influence of an observer's sex and values on aggressive responding.

Two experiments investigated the effects of the presence of an observer on aggressive responding. In one experiment, male subjects observed by a male aggressed more than those observed by a female. When the male observer was removed from the situation, subjects' level of aggressiveness more closely matched the level manifested by the opponent. The removal of the female observer had little effect on the subjects' behavior. In the second experiment, the male or female observer of the subject's behavior was disguised as a member of an organization with explicit values (aggressive or pacifistic) regarding the use of aggression. In this case, significant differences in aggression were associated with the observer's values but not the observer's sex. Following the departure of the observer, the shock settings of subjects in the two aggressive-value observer groups showed a signifcant decrease. The average shock setting of subjects in the two pacifistic-value observer groups remained at about the same level. In sum, the results indicated that the subjects' aggressive behavior was apparently a function of their expectations of approval for such behavior, based on the inferred or explicit values of the observer. The results were further discussed in terms of social learning theory.     

Effects of clean and soiled sawdust substrates and of different urine types upon aggressive behavior in male mice

The effects of sawdust taken from the cages of grouped or isolated male mice upon the aggressiveness of trained fighter mice toward castrated opponents were examined. The results indicate that (1) substrate soiled by stable groups of male mice does not provide aggression-promoting odors, (2) application of the urine of isolate male mice to castrate opponents increases the aggressiveness of fighters toward the castrates, and (3) application of isolate male urine to the test substrate inhibits the aggressive behavior of a fighter toward its castrated opponent. The concepts that male mouse urine possesses both aggression-promoting and aggression-inhibiting cues are not mutually exclusive, but the action of the urine depends upon whether it is placed onto a mouse or onto the substrate. The findings are discussed in relation to those of previous studies on soiled sawdust and aggression, and an attempt is made to relate these results to a territorial situation.     

The disguise of sobriety: unveiled by alcohol in persons with an aggressive personality

This investigation examined the factor structure of 8 well-validated self-report measures that assess traits that fall under the rubric of an "aggressive personality" and then determined how those factor(s) moderated the association between alcohol intoxication and aggression. Participants were 518 (252 men and 266 women) healthy social drinkers between 21 and 35 years of age. Following the consumption of an alcoholic or a placebo beverage, participants were tested on a laboratory aggression paradigm in which electric shocks were received from, and administered to, a fictitious opponent. Aggression was operationalized as the shock intensities and durations administered to the opponent. Results demonstrated a unidimensional factor structure for the aggressive personality traits, which were then combined into a latent variable. The aggressive personality variable moderated the alcohol-aggression relation. Specifically, alcohol was significantly more likely to increase aggression in persons with higher, compared with lower, aggressive personality scores.     

Effect of anosmia on the behavior of standard non-aggressive male mice opponents during agonistic encounters

This study assessed whether the differences observed in a previous experiment [Martinez M, Salvador A, Simon VM (1994): Aggressive Behavior 20:441–451] in the behavior of isolated male mice over several agonistic encounters in which they confronted either an “anosmic” or an “intact” non-aggressive “standard opponent” were due to the differences in the behavior of the opponents themselves. Ethologically-inspired analysis was used to assess the behavior of the opponents during the first agonistic encounter. Anosmic opponents spent less time in social investigation and defense and more time in immobility than intact ones. These results suggest that the differences in the behavior of the opponents could be one of the causes of the differences observed in the behavior of the aggressive males confronting them. However, more research is needed to study if other variables, such as the production of odors, are also affected by the state (deprived or intact) of the olfactory sense. These findings provide additional support for the view that the type of opponent used in studies on intermale aggression is of paramount importance.Aggr. Behav. 23:179–181, 1997.© 1997 Wiley-Liss, Inc.     

Third party instigated aggression as a function of attack pattern and a nonaggressive response option

In the present study, subjects suggested what shock intensity a confederate should set for her opponent in a reaction time competition. Opponents displayed one of three attack patterns: increasing, decreasing, or minimal provocation. Also, for half the subjects a “no shock” option was available. A control group who had the nonaggressive option and for whom the opponent was nonaggressive (always chose “no shock”) was included. Results revealed that subjects' responses were governed by the norm of reciprocity; also the option reduced instigative aggression for subjects encountering increasing and decreasing provocation, while elevating aggressive response when the opponent was minimally provocative. Results are discussed in terms of attribution and locus of control.     

Imitation of Self‐Aggressive Behavior: An Experimental Test of the Contagion Hypothesis1

The purpose of the present study was to experimentally examine the influence of a self‐aggressive model on self‐aggressive behavior under controlled laboratory conditions. Participants (N= 94) were given the opportunity to self‐administer electric shock while competing with a fictitious opponent in a reaction‐time task. Participants observed the opponent self‐administer either increasingly intense shock (a self‐aggressive model) or constant low shocks (a non‐self‐aggressive model). Self‐aggression was defined as the intensity of shock that was self‐administered by participants. Results provide support for the notion that social information can influence the expression of self‐aggressive behavior. Specifically, participants attended to the opponent's shock choices in both model conditions, and chose shocks consistent with those of the observed model.     

Attacker's intent and awareness of outcome,impression management,and retaliation

Female Japanese students who were engaged in a calculation task were given electric shocks by a female opponent. The subjects were informed that the opponent had an intent to shock them either severely or mildly. In addition, the opponent's awareness of the outcome of attack was independently manipulated: (1) the subjects received shocks whose intensity corresponded to the opponent's intent, (2) the subjects received shocks whose intensity was inversely proportional to the intensity intended by the opponent and were informed that the opponent did not know about it, or (3) the subjects received reversed shocks as in condition (2), but were further informed that the opponent was well aware of it. An ANOVA of the measure of retaliation in terms of the intensity of shocks delivered to the opponent indicated that (1) the subjects showed more aggression of greater intensity against an opponent who apparently had an aggressive intent than the one who did not, regardless of the actual level of shock intensity; (2) when the severe attack failed, the subjects lowered aggression when the opponent was apparently aware of it as opposed to when she was not; and (3) when the subjects received severe shocks accidentally, they increased aggression when the opponent was apparently aware of it compared to when she was not. These results led us to interpret retaliation as being mediated both by the attribution of intent to the attacker and by self-presentation to the attacker and the experimenter.     

Effects of the heterosomes and maternal environments on aggressive behavior in Mus musculus

This is a study of the offense type of aggression in males of the DBA/1Bg and C57BL/10Bg inbred strains of mice and their two reciprocal F1 hybrids. It uses three test paradigms for dyadic encounters: the homogeneous set test, an identity panel of testers, and the standard opponent test. There were no reciprocal F1 hybrid differences for any of the 12 behavioral measures of aggression in the homogeneous set test or the standard opponent test. For the panel of testers paradigm, reciprocal F1 hybrid differences occurred when the tester (opponent) was an F1 hybrid male, but not when the tester (opponent) was an RB/1 or C57BL10 male. When B10RB1F1 males were the testers (opponents), B10RB1F1 hybrid males were more aggressive than RB1B10F1 hybrid males across 10 of the 12 behavioral measures. Conversely, when RB1B10F1 males were the testers (opponents), RB1B10F1 males were more aggressive than B10RB1F1 males across 9 of the 12 behavioral measures. These results conform to the following empirical rule: A significant difference between reciprocal F1 hybrids is observed for these behavioral measures when one of the hybrids has both of its heterosomes (X and Y chromosomes) and its maternal environment identical to those of its opponent and the other hybrid has none of these identical to those of its opponent. These results are consistent with a model in which on some genetic backgrounds, but not on others, similarity of the heterosomes and maternal environments can influence the display of or response to social or other stimuli for the offense type of aggression in mice. These stimuli may be individual recognition chemosignals in urine.