Aggression Bias Research Articles

Development and Validation of an Explicit Aggressive Beliefs and Attitudes Scale

This work outlines the development and validation of a new self-report measure that assesses explicit aggressive beliefs and attitudes within the normal adult population (using 7 samples, total N = 3,533). These explicit aggressive beliefs and attitudes are expected to reflect aggressive biases including hostile attribution, potency, retribution, victimization by powerful others, derogation of target, and social discounting. The resulting scale is reliable with a hierarchical 6-factor structure, and displays convergent and discriminant validity. Criterion-related validity studies indicate incremental effects over socially desirable response bias, related implicit and explicit aggression measures, and is predictive of self-reported and other-reported aggression-related behaviors.

Signal and preference divergence among populations of the non-endemic basal Lake Malawi cichlid fishAstatotilapia calliptera(Perciformes: Cichlidae)

In Lake Malawi and Lake Victoria, cichlid fishes have diversified into hundreds of species, many reproductively isolated by mate choice. Territorial males tend to be more aggressive to similar-coloured males, facilitating coexistence of divergent colour morphs or species. Behavioural mate choice and aggression biases of species and allopatric populations of specialized rocky shore cichlids are influenced by divergent signals such as male colour. Believed to be basal to the Lake Malawi haplochromine radiation, and inhabiting shallow weedy areas of the lake and neighbouring water bodies, Astatotilapia calliptera also shows allopatric variation in colour. Here, it is demonstrated that such signal divergence is associated with tendencies of females to mate with males of their own population and also for males to preferentially attack males of their own population, indicating that preference divergence related to signal divergence in allopatry may have operated throughout the adaptive radiation of the Malawian cichlids. © 2013 The Linnean Society of London, Biological Journal of the Linnean Society, 2013, 110, 180–188.

A test of genetic association among male nuptial coloration, female mating preference, and male aggression bias within a polymorphic population of cichlid fish

Abstract Both interand intrasexual selection have been implicated in the origin and maintenance of species-rich taxa with diverse sexual traits. Simultaneous disruptive selection by female mate choice and male-male competition can, in theory, lead to speciation without geographical isolation if both act on the same male trait. Female mate choice can generate discontinuities in gene flow, while male-male competition can generate negative frequency-dependent selection stabilizing the male trait polymorphism. Speciation may be facilitated when mating preference and/or aggression bias are physically linked to the trait they operate on. We tested for genetic associations among female mating preference, male aggression bias and male coloration in the Lake Victoria cichlid Pundamilia. We crossed females from a phenotypically variable population with males from both extreme ends of the phenotype distribution in the same population (blue or red). Male offspring of a red sire were significantly redder than males of a blue sire, indicating that intra-population variation in male coloration is heritable. We tested mating preferences of female offspring and aggression biases of male offspring using binary choice tests. There was no evidence for associations at the family level between female mating preferences and coloration of sires, but dam identity had a significant effect on female mate preference. Sons of the red sire directed significantly more aggression to red than blue males, whereas sons of the blue sire did not show any bias. There was a positive correlation among individuals between male aggression bias and body coloration, possibly due to pleiotropy or physical linkage, which could facilitate the maintenance of color polymorphism.

2246 – Attribution bias in early-onset-schizophrenia: relationship to clinical features

Attribution style bias, such as a greater tendency to perceive hostility, has been reported to be presented in multi-episode and chronic schizophrenia patients. The aim of this study was to investigate whether adolescents with Early-Onset-Schizophrenia (EOS) exhibited a perceived hostility bias and whether this bias was correlated with adolescents' clinical characteristics (positive and negative symptoms of schizophrenia, anxiety, depression, self-esteem) and social competence (social behavior, communication, imagination). Thirteen adolescents with EOS (mean age: 14.7) and 17 healthy adolescents (mean age: 14.2), matched on age and total IQ, completed the Ambiguous Intentions Hostility Questionnaire (AIHQ) and several clinical measures of anxiety, depression, social competences and self-esteem. The AIHQ is a self-report questionnaire about negative outcomes that varied intentionality in different situations (i.e., ambiguous, intentional and accidental situations). The perceived hostility, composite blame and aggression bias scores were calculated. In comparison with healthy adolescents, adolescents with EOS attributed more hostile intentions to persons in accidental situations (hostility bias); they also exhibited a higher level of negative emotions (blame bias) toward persons in accidental situations. Both, hostility bias and blame bias were associated with a higher level of anxiety and a lower selfesteem in EOS adolescents. These results suggest that cognitive and emotional biased attribution style in EOS may constitute an important factor of vulnerability to social impairments in adolescents with EOS and suggest that these attributional biases should constitute the targets of early psychotherapeutic intervention with these patients.

Reliability and validity of the Chinese-version of the ambiguous intentions hostility questionnaire

Objective To evaluate the reliability and validity of the Chinese-version of the Ambiguous Intentions Hostility Questionnaire(AIHQ-C). Methods 303 healthy subjects and 202 schizophrenic patients were asked to completed the AIHQ-C along with measures of Paranoia Scale (Pa). Two weeks later, 110 healthy subjects and 70 schizophrenic patients who were randomly selected from the total sample completed the AIHQ-C again to compute the test-retest reliability. The criterion-related validity was evaluated by correlating the AIHQ-C with Pa. Results (1)The Cronbach α coefficient of total Hostility Bias(THB), total Blame Bias(TBB) and total Aggression Bias(TAB) for the AIHQ-C was 0.78, 0.94, 0.84(P<0.01) respectively, and the Cronbach α coefficient of Hostility Bias(HB), Blame Bias(BB)and Aggression Bias(AB)for each situation of the AIHQ-C was between 0.51 and 0.90. The test-retest reliability of THB, TBB and TAB for the AIHQ-C was 0.71, 0.73, 0.68(P<0.01) respectively, and the test-retest reliability of HB, BB and AB for each situation of the AIHQ-C was between 0.48 and 0.73. (2) Pa was positively correlated with THB, TBB and TAB (r=0.51, 0.37, 0.41, P<0.01, respectively) and the correlation coefficients of HB, BB and AB for each situation of the AIHQ-C with Pa was between 0.23 and 0.52. The results indicated that the AIHQ-C had good criterion-related validity. (3)Schizophrenic patients had higher scores of the AIHQ-C than the healthy subjects, it suggested that the AIHQ-C had good discriminant validity. Conclusion The AIHQ-C has good reliability and validity in application to Chinese people. Key words: Hostility; Attribution; Scale; Reliability; Validity; Schizophrenia

Morph Matters: Aggression Bias in a Polymorphic Sparrow

In species with discrete morphs exhibiting alternative behavioral strategies, individuals may vary their aggressive behavior in competitive encounters according to the phenotype of their opponent. Such aggression bias has been documented in multiple polymorphic species evolving under negative frequency-dependent selection, but it has not been well-studied under other selection regimes. We investigated this phenomenon in white-throated sparrows (Zonotrichia albicollis), a passerine with plumage polychromatism maintained by disassortative mating. The two distinct color morphs differ with respect to reproductive strategy in that white-striped birds invest more in territorial aggression than tan-striped birds. Whether territorial aggression in this species is biased according to the morph of an intruder is less understood. We found that during peak territorial and mating activity, both color morphs and sexes can exhibit aggression bias, but whether they do so depends on the strategy (morph) of the intruder. During simulated territorial intrusions, resident white-striped males and tan-striped females, which represent the opposite ends of a continuum from high to low territorial aggression, altered their territorial responses according to intruder morph. Tan-striped males and white-striped females, which represent the middle of the continuum, did not show a bias. We propose that because of the disassortative mating system and morph differences in reproductive strategy, the fitness risks of intrusions vary according to the morphs of the resident and the intruder, and that aggression bias is an attuned response to varying threats to fitness.

The relationship among the aggressive behavior, hostile attribution bias and childhood trauma in schizophrenic patients

Objective To explore the relationship among the aggressive behavior, hostile attribution bias and childhood trauma in schizophrenic patients. Methods 135 schizophrenic patients were tested with Modified Overt Aggression Scale (MOAS), the Chinese-version of the Ambiguous Intentions Hostility Questionnaire (AIHQ-C) and Childhood Trauma Questionnaire (CTQ). According to the score of the MOAS, the patients were divided into the aggressive group (n=58) and the non-aggressive group (n=77). The hostile attribution bias and the childhood trauma were compared between the two groups, and correlation and hierarchical regression analysis were used to investigate the relationships of the variables. Results Compared with the non-aggressive patients, the aggressive patients had significantly higher AIHQ-C total hostility bias score (6.27±1.20 vs 5.90±0.97, P<0.05), total blame bias score (8.04±1.97 vs 6.91±2.10, P<0.01) and total aggression bias score (6.17±1.02 vs 5.59±1.04, P<0.01). Correlation analysis showed that the MOAS score, AIHQ scores and the total score of CTQ were significantly positively correlated with each other (r=0.171~0.350, P<0.05~0.01). Regression analysis indicated the hostile attribution bias directly predicted the aggressive behavior(β=0.342, P<0.05)and completely mediated the relationship between the childhood trauma and the aggressive behavior. Conclusion The aggressive behavior in schizophrenic patients is associated with the experience of childhood trauma and the attribution style. The childhood trauma indirectly influences the aggressive behavior by the mediating of the hostile attribution bias. Key words: Schizophrenia; Aggressive behavior; Hostility; Attribution; Childhood Trauma

Does distraction reduce the alcohol–aggression relation? A cognitive and behavioral test of the attention-allocation model.

This study provided the first direct test of the cognitive underpinnings of the attention-allocation model and attempted to replicate and extend past behavioral findings for this model as an explanation for alcohol-related aggression. A diverse community sample (55% African American) of men (N = 159) between 21 and 35 years of age (M = 25.80) were randomly assigned to 1 of 2 beverage conditions (i.e., alcohol, no-alcohol control) and 1 of 2 distraction conditions (i.e., distraction, no-distraction). Following beverage consumption, participants were provoked via reception of electric shocks and a verbal insult from a fictitious male opponent. Participants' attention allocation to aggression words (i.e., aggression bias) and physical aggression were measured using a dot probe task and a shock-based aggression task, respectively. Intoxicated men whose attention was distracted displayed significantly lower levels of aggression bias and enacted significantly less physical aggression than intoxicated men whose attention was not distracted. However, aggression bias did not account for the lower levels of alcohol-related aggression in the distraction, relative to the no-distraction, condition. These results replicated and extended past evidence that cognitive distraction is associated with lower levels of alcohol-related aggression in highly provoked males and provide the first known cognitive data to support the attentional processes posited by the attention-allocation model. Discussion focused on how these data inform intervention programming for alcohol-related aggression.

Financial Policies and Hedging

While firms commonly benchmark corporate financial policies against industry peers, empirically, some firms consistently deviate to pursue “rogue” policies with either a conservative or an aggressive bias. Using a panel of large U.S. firms between 1975 and 2008, we study the incidence, joint frequency distribution, and valuation effect of conservative and aggressive financial policies across four policy dimensions: leverage, payout, liquidity, and risk management. Consistent with a hedging effect, we find that conservative (aggressive) financial policies are generally associated with higher (lower) valuations. In addition, consistent with hedging theories, we find that firms with high growth opportunities which also face financial constraints benefit more from conservative financial policies. We also observe a time-variation in the valuation effects. For example, we find that conservative liquidity policies are associated with lower valuation benefits during periods of high economic growth while most aggressive policies are associated with even lower valuations as the average level of the policy increases. Finally, our tests of joint rogue policies provide evidence consistent with agency explanations. For example, firms which pursue both conservative leverage and conservative liquidity policies are valued at a discount, even though those that pursue a conservative leverage or a conservative liquidity policy on its own are valued at a premium.

Male territoriality and ‘sex confusion’ in recently adapted lizards at White Sands

The evolution of intersexual interactions, like mate choice, during ecological speciation has received widespread attention. However, changes in intrasexual interactions, like male territoriality, during ecological divergence are largely unexamined. We conducted field experiments with adaptively diverged populations of the eastern fence lizard (Sceloporus undulatus) to determine whether territorial males behaved differently towards ecologically similar vs. dissimilar intruders. We performed trials with light-coloured males from White Sands, New Mexico and dark-coloured males from the surrounding desert. We found that intruders from White Sands elicited more aggression than intruders from dark-soil habitat. We also documented a case of 'sex confusion' where white-sand males courted dark-soil intruders. We found population differences in signalling patch size that can explain both aggression bias and sex misidentification. We argue that direct selection (for population recognition or optimal signal transmission) and indirect selection (by-products of ecological adaptation) should influence both intersexual and intrasexual interactions during ecological speciation.

Sympatric colour polymorphisms associated with nonrandom gene flow in cichlid fish of Lake Victoria

Colour polymorphisms have fascinated evolutionary ecologists for a long time. Yet, knowledge on the mechanisms that allow their persistence is restricted to a handful of well-studied cases. We studied two species of Lake Victoria cichlid fish, Neochromis omnicaeruleus and Neochromis greenwoodi, exhibiting very similar sex-linked colour polymorphisms. The ecology and behaviour of one of these species is well studied, with colour-based mating and aggression preferences. Here, we ask whether the selection potentially resulting from female and male mating preferences and aggression biases reduces gene flow between the colour morphs and permits differentiation in traits other than colour. Over the past 14 years, the frequencies of colour morphs have somewhat oscillated, but there is no evidence for directional change, suggesting the colour polymorphism is persistent on an ecological timescale. We find limited evidence of eco-morphological differentiation between sympatric ancestral (plain) and derived (blotched) colour morphs. We also find significantly nonrandom genotypic assignment and an excess of linkage disequilibrium in the plain morph, which together with previous information on mating preferences suggests nonrandom mating between colour morphs. This, together with negative frequency-dependent sexual selection, found in previous studies, may facilitate maintenance of these polymorphisms in sympatry.

Attribution bias in ultra-high risk for psychosis and first-episode schizophrenia

BackgroundAttribution style bias, such as a greater tendency to perceive hostility, has been reported to be associated with paranoia in multi-episode, chronic schizophrenia patients. The aim of this study was to investigate whether young, first-episode schizophrenia patients exhibited a perceived hostility bias and if this bias was correlated with persecutory symptoms. This study also explored whether this attribution bias, associated with paranoid tendencies, also emerged in participants at ultra-high risk (UHR) for psychosis. MethodsThirty-nine normal controls, 24 UHR participants, and 20 young, first-episode schizophrenia patients were asked to complete the Ambiguous Intentions Hostility Questionnaire (AIHQ) and other psychosocial measures. The AIHQ, specifically developed for paranoia, is a self-report questionnaire about negative outcomes that varied intentionality (i.e., intentional, accidental, and ambiguous intentions). The perceived hostility, composite blame, and aggression bias scores were calculated, in this study, from the ambiguous situations. ResultsFirst-episode patients with schizophrenia were found to have a perceived hostility bias, which was associated with persecutory symptoms. The UHR participants also showed an attribution bias for perceiving hostility and blaming others, and this attribution bias was linked to the paranoia process. ConclusionsThese findings suggest that a biased attribution style linked with paranoid symptoms may not only be present in first-episode psychotic patients but may already have evolved prior to the onset of frank psychotic symptoms. A biased attribution style may play a pivotal role in the persecutory process during the prodromal phase as well as a patient's first schizophrenic episode.

Mandatory audit firm rotation: Fresh look versus poor knowledge

Our aim in this paper is to investigate the effects of mandatory audit firm rotation (MAR) on companies’ investment decision and auditor choice in a capital market setting. We compare a MAR regime with a non-MAR regime in a setting in which auditors’ independence and companies’ opinion shopping are real concerns. To capture auditor independence and opinion shopping, we model auditor biases (a conservative bias or an aggressive bias) and client firms’ incentives to engage auditors with desired biases. We find that when firms engage in opinion shopping, MAR improves investment efficiency for some firms but impairs investment efficiency for other firms. More generally, we contribute to the literature by demonstrating the real effects of auditing on corporate resource allocation decisions.

Cross‐fostering Does Not Influence the Mate Preferences and Territorial Behaviour of Males in Lake Victoria Cichlids

AbstractThe ability to recognise conspecifics in contexts of mate choice and territorial defence may have large effects on an individual’s fitness. Understanding the development of assortative behaviour may shed light on how species assortative behaviour evolves and how it may influence reproductive isolation. This is the case not only for female mate preferences, but also for male mate preferences and male territorial behaviour. Here we test with a cross‐fostering experiment whether early learning influences male mate preferences and male–male aggression biases in two closely related, sympatrically occurring cichlid species Pundamilia pundamilia and Pundamilia nyererei from Lake Victoria. Males that had been fostered, either by a conspecific female or by a heterospecific female, were tested for their aggression bias, as well as for their mate preferences, in two‐way choice tests. Males cross‐fostered with conspecific and heterospecific foster mothers selectively directed their aggression towards conspecific intruders. The cross‐fostering treatment also did not affect male mate preferences. These results are in striking contrast with the finding that females of these species show a sexual preference for males of the foster species.

An experimental study of aggressive and neutral interpretative bias in opiate-dependent and opiate-abstinent men

There is a paucity of research on the relationship between opiate use and aggression, and no previous study has examined this from a cognitive theoretical perspective, which views an individual's interpretation of information as a central mediator of their response to it. This study aimed to determine whether opiate users and ex-users differed from opiate-naïve controls on a task which involved processing ambiguous sentences. In an independent group design, the interpretative bias task was administered to 64 participants: 21 opiate-dependent receiving methadone maintenance treatment, 21 opiate-abstinent in rehabilitation, and 22 healthy unemployed controls. We found that both opiate-dependent and opiate-abstinent groups interpreted ambiguous sentences in a neutral rather than an aggressive way, whereas controls showed no bias in either direction. In the opiate-dependent group, neutral interpretative bias correlated both with their current dose of methadone and years of methadone use. These findings indicate that current and ex-opiate users in treatment have a bias towards neutral interpretations of ambiguous information. The fact that neutral interpretative bias in opiate-dependent individuals correlated with current dose and years of methadone use suggests that methadone treatment is associated with a neutral cognitive bias. Decreased testosterone levels associated with chronic opiate use may underpin this neutral bias.

Learned aggression biases in males of Lake Victoria cichlid fish

Male–male competition for mating territories can exert negative frequency-dependent selection on a male secondary sexual trait, such as nuptial coloration. This can occur when males bias aggression towards own-coloured competitors, resulting in a fitness advantage for rare phenotypes, thereby promoting the evolution and maintenance of stable colour polymorphisms. It could operate in the extensive radiations of haplochromine cichlid fish in East African lakes. In a previous investigation we studied wild-caught blue and red Pundamilia males from Lake Victoria; males from a location where most resemble blue (referred to as bluish males) biased aggression towards blue stimulus males. In contrast, blue males from a location where blue and red occur sympatrically biased aggression towards red stimulus males. Using lab-bred bluish and blue males, we tested the hypothesis that exclusive experience with blue males (blue treatment) leads to an aggression bias towards blue and that experience with blue and red males (mixed treatment) leads to an aggression bias towards red. Contrary to predictions, blue-treated males did not distinguish between blue and red males, whereas mixed-treated males preferentially attacked blue stimulus males. The data suggest that prior experience can affect aggression biases and that experience with more than one phenotype may be required for the development of biases. Yet, our results cannot explain the direction of differences in specific biases observed in wild-caught males from different populations.

Relational Aggression and Response Decision Biases in Social Information Processing in Australian Adolescent Females

AbstractRelational aggression is becoming increasingly recognized as a very prevalent behaviour amongst females, especially within school settings. Robust findings have supported N.R Crick and K.A. Dodge's Social Information Processing Model (1994) as being a useful model in explaining physical aggression amongst males. However, little research has examined the model with regards to relational aggression in females and research that does exist has shown inconsistent findings. The current study examined the fifth step of the model, Response Decision, in a sample of female adolescents. The four factors that have previously been identified as contributing to the response decision step were examined, including response evaluation, outcome expectancies, self-efficacy evaluation, and response selection. In view of suggestions made by W.F.Arsenio and E.A.Lemerise (2004), level of moral reasoning was also examined with regard to how relationally aggressive responses were evaluated. These factors were examined within hypothetical relationally aggressive peer situations in relationally aggressive, overtly aggressive, relationally plus overtly aggressive and non-aggressive participants. The results show that compared to non-aggressive and overtly aggressive females, relationally aggressive females show a bias in the four processes of the response decision step. Differences in levels of moral reasoning were also found between the different aggression type groups. Hence the findings provide support for Crick and Dodge's (1994) Social Information Processing model in explaining relationally aggressive behaviour. The findings are discussed with regards to their implications for educational settings.

Females learn from mothers and males learn from others. The effect of mother and siblings on the development of female mate preferences and male aggression biases in Lake Victoria cichlids, genus Mbipia

While species-assortative behaviour is often observed in sympatrically occurring species, there are few examples where we understand the extent to which development of assortative behaviour is genetically or environmentally determined, for instance, through learning. However, the majority of mate choice theory assumes genetic recognition mechanisms. Knowledge about the development of species recognition is important for our understanding of how closely related species can coexist and how this coexistence may have arisen. The ontogeny of female mate choice, for instance, may critically influence the degree of assortative mating under many circumstances. Also, male assortative aggression behaviour may affect fitness and the possibility for coexistence of two closely related species. Here, we test whether male aggression biases and female mate preferences of two Lake Victoria rock cichlid species, Mbipia mbipi and Mbipia lutea, are affected by experience. With an interspecific cross-fostering experiment, we test for the effect of experience with the phenotype of the mother and that of the siblings on species-assortative mate preferences and aggression biases. We demonstrate that female mate preferences are strongly influenced by learning about their mothers’ phenotype but not by experience with their siblings, despite ample opportunity for interactions. Male aggression biases, in contrast, are affected by experience with siblings but not by learning about their mothers’ phenotype. We suggest that the development of assortative behaviour of females, but not of males, creates favourable conditions for sympatric speciation in Lake Victoria cichlids.

Aggressive biases towards similarly coloured males in Lake Malawi cichlid fishes

In haplochromine cichlids, female mate choice based on male nuptial coloration has played an important role in speciation. Recent studies suggest that male coloration strongly influences the distribution of these fishes based on male-male aggression; males direct more aggression towards similarly coloured opponents while tolerating differently coloured individuals. We explored the role of male nuptial colour in aggression among the mbuna of Lake Malawi, examining aggression by male Metriaclima mbenjii, the red top cobalt zebra, towards conspecific opponents, similarly coloured heterospecific opponents and differently coloured heterospecifics. In trials in which focal males were offered a single opponent, while the total number of aggressive behaviours did not vary among opponent species, the types of behaviours did; focal males directed more lateral displays towards conspecifics than towards the other opponent species. When focal males were offered two opponents simultaneously, M. mbenjii directed more aggressive behaviours and more lateral displays towards similarly coloured opponents, regardless of species. Furthermore, when offered a conspecific and a similarly coloured opponent simultaneously, there were no differences in behaviour towards either opponent. Thus, nuptial coloration is used by males to identify competitors, and it suggests that male-male aggression may have also been an important diversifying force in speciation in rock-dwelling Lake Malawi cichlids.

Intrasexual competition among females and the stabilization of a conspicuous colour polymorphism in a Lake Victoria cichlid fish

The maintenance of colour polymorphisms within populations has been a long-standing interest in evolutionary ecology. African cichlid fish contain some of the most striking known cases of this phenomenon. Intrasexual selection can be negative frequency dependent when males bias aggression towards phenotypically similar rivals, stabilizing male colour polymorphisms. We propose that where females are territorial and competitive, aggression biases in females may also promote coexistence of female morphs. We studied a polymorphic population of the cichlid fish Neochromis omnicaeruleus from Lake Victoria, in which three distinct female colour morphs coexist: one plain brown and two blotched morphs. Using simulated intruder choice tests in the laboratory, we show that wild-caught females of each morph bias aggression towards females of their own morph, suggesting that females of all three morphs may have an advantage when their morph is locally the least abundant. This mechanism may contribute to the establishment and stabilization of colour polymorphisms. Next, by crossing the morphs, we generated sisters belonging to different colour morphs. We find no sign of aggression bias in these sisters, making pleiotropy unlikely to explain the association between colour and aggression bias in wild fish, which is maintained in the face of gene flow. We conclude that female-female aggression may be one important force for stabilizing colour polymorphism in cichlid fish.