Stress and Intimate Partner Aggression

Abstract

Evidence suggests that stressed couples also tend to be aggressive couples. Chronic external stresses interact with individuals’ dispositional and regulatory deficiencies, resulting in a spillover of these stresses into the relationship. High individual stress in combination with problematic interaction styles and problem-solving abilities increases the likelihood of IPA. We applied the I³ Model to better organize the instigating, impelling, and inhibiting factors and processes that moderate the stress-IPA association. Evidence suggests that certain forms of stress, such as IPA victimization, reliably instigate IPA perpetration, with weak inhibitory processes and impaired problem solving moderating the stress-IPA association. More research is needed that specifies the ‘perfect storm’ of factors that increase our understanding of how, and for whom, stress increases IPA risk.

To be in a close relationship is to share one’s life with another, with all the positives as well as the stresses and strains that accompany two lives intertwined. And despite what relationships appear to be on social media or in discussions with friends or family, so much of everyday life in a close relationship involves the management of a multitude of stressors. Such stressors can be external to the relationship (e.g., paying bills on time, health concerns, job stress, neighborhood disadvantage), while others emerge from factors internal to the relationship (e.g., negative / escalating interaction styles, disagreements about parenting, work-life balance). Is there a particular stressful life event threshold such that anyone who experiences stress above that level is likely to act aggressively towards a relationship partner? We argue that the evidence suggests the contrary; that is, consistent with existing stress-vulnerability frameworks [1,2], the direct relationship between stress and IPA [3] can be better understood as certain at-risk individuals being more susceptible to the effects of stress on IPA perpetration. Thus, stress is neither a necessary nor sufficient cause of IPA – practical and clinical experiences suggest that people can be highly resilient even in the face of numerous and/or severe stressors [4]. For some individuals, however, the experience of stress interacts with existing personal vulnerabilities (e.g., dispositional factors, trauma history, etc.) to augment the effects of any single individual risk factor to increase the risk of IPA. In such situations, the stressor is likely to interact with this personal vulnerability to produce more personal and relational distress, which in turn may spillover into greater relationship conflict and a higher likelihood of IPA.

Stress-Vulnerability Models of Stress and IPA

While the bulk of prior research on stress has approached this construct as a phenomenon that primarily affects individuals, understanding the stress-IPA association requires a dyadic perspective [5]. Dyadic stress refers to a stressful event or encounter that involves both partners, either because each are exposed to the same stressful event, or because one partner’s stress spills over into the relationship and affects the dyad [6]. Models positing an interaction between the presence of stress and a variety of contextual and dispositional factors in predicting important dyadic outcomes are not new [5]. Stress-vulnerability models outlining the impact of stress in couples and families have been in existence since the 1940’s [7]. These models have long noted the interplay between (a) the severity of acute and ongoing stressors, and (b) the quality of the couples’ problem solving abilities as key determinants of relationship health [8,9]. Subsequent models [1,6] have refined this approach by highlighting the role of individual vulnerabilities (e.g., neuroticism, traumatic childhood experiences) and various individual and dyadic maladaptive processes for coping with major stressors (e.g., poor empathy; hostile interaction styles). Of note, these researchers have shown that chronic minor daily stresses can be just as toxic to relationship functioning as more short-term major stresses [6]. In the specific context of IPA, Leonard’s [2] contextual model also suggests that stress plays a prominent role in understanding partner abuse, but primarily in the context of existing individual and dyadic vulnerabilities.

Thus, existing models suggest that the link between stress and IPA is moderated by an interdependent mix of (a) state and trait factors internal to the person, (b) situational/contextual factors, and (c) impaired ability to manage reactions to stress. The relatively small amount of research on this topic confirms the utility of this approach. In addition to a main effect of stress on IPA [3,10], the stress-IPA association is also moderated by the following variables: gender, with males exhibiting stronger stress-IPA associations [11,14]; high self-esteem [11], lack of closeness to one’s parent [11], poor emotion regulation [15], use of escalating strategies during relationship conflict [15], high masculine sex role ideology [16], greater levels of childhood adversity [17], greater attachment anxiety [12], neuroticism [18], and prior and/or recent IPA victimization [10,19]. In addition, the stress-IPA association is stronger in: military (vs. civilian) samples [14], clinical (vs. community) samples [13,14], individuals with more PTSD symptoms (rather than presence/absence of a diagnosis) [14], and in studies using standardized measures of marital discord [13].

Stress, IPA, and Instigating, Impelling, and Inhibiting Factors

It is clear that stress interacts with a variety of factors to increase risk for IPA. The remaining questions that are not addressed by existing stress-vulnerability models are (1) how best to organize the diverse set of interactive risk factors for IPA, and (2) how to dynamically model how such factors actually work to increase IPA risk. To address these limitations, we have applied the I³ Model (“I-Cubed”) to this association as a process-focused, metatheoretical model providing an organizational structure and dynamic model for predicting behavior [20,21], including IPA [22]. The I³ Model begins with the basic assumption that people are more likely to perpetrate IPA when the strength of the urge to aggress exceeds the strength of the inhibitory forces counteracting this urge. According to the model, three key processes underlie IPA perpetration: instigation, impellance, and inhibition (with the italicized vowels representing the three Is in the I³ Model). Instigation refers to the exposure to discrete situational events that are normatively provoking. Such events can trigger hostile cognitive, affective, physiological, and even preliminary behavioral tendencies that prime individuals to aggress [23]. Impellance refers to the amplification of the urge to aggress in response to instigation. In some situations, people may shrug off an instigating trigger, while others may react strongly and experience a powerful aggressive urge. Finally, inhibition refers to the counteraction to this urge. When the strength of inhibition exceeds the strength of the urge to aggress, people behave non-aggressively; when the reverse is true, they behave aggressively. The main theory drawn from the I³ Model is known as “perfect storm theory,” [20] which posits that the greatest likelihood for IPA occurs when instigation and impellance processes are strong and inhibitory processes are weak (Figure 1). In the following section, we apply the I³ Model in order to better understand the moderated associations between stress and IPA.

Figure 1.

The I³ Model predicts that IPA results from a combination of instigating, impelling, and inhibiting factors. The main theory drawn from the I³ Model is known as “perfect storm theory”, which posits that the greatest likelihood for IPA would occur when instigation and impellance processes are strong and inhibitory processes are weak.

Instigation

The bulk of stressful life events are not inherently aggressogenic. However, certain types of dyadic stressors appear to be reliably provocative and instigating. One of the strongest predictors of IPA perpetration is recent IPA victimization [24,25]. In the context of the I³ model, being a target of a partner’s psychological or physical aggression is a powerful source of instigation that sets the contextual stage for an aggressive response [19], especially when combined with additional impelling and disinhibiting factors [26]. In addition, relationship discord is moderately associated with IPA perpetration [13] and is therefore a potentially aggressogenic context. However, findings from longitudinal studies indicate that improvements in marital satisfaction do not necessarily lead to reductions in IPA [18,27]. It is also likely that while many everyday stressors are not inherently aggression instigating, the dyadic experience of stress may trigger existing relational processes that become instigating (e.g., arguments about family that involve insulting, contemptuous, and belligerent interaction styles).

Impellance

Research suggests that certain dispositional factors moderate the association between stressful life events and IPA. Higher levels of dating aggression were observed in stressed adolescents with high self-esteem and low levels of closeness to a parent [11]. In a longitudinal study of married couples, high levels of neuroticism and high relationship distress predicted IPA over a four-year period, especially among those with poor problem solving behaviors (i.e., diminished inhibition) [18]. While this literature is somewhat sparse, the available data suggest that impelling factors may interact with stressful life events in ways that further destabilize dyadic adjustment and that construct a clear pathway to an aggressive response.

Inhibition/Disinhibition

Whether partners continue down the path towards aggression largely depends on the quality and availability of individual and dyadic aggression inhibiting factors. Such factors have been a central component of models of dyadic stress [1,6,7], which posit that many different types of stress, but especially minor stressful events existing outside the relationships, spill over into the relationship context and activate individual adaptive coping and problem-solving responses. These responses are enacted in the broader context of the couple’s prevailing communication patterns and interactional style. To the extent that individuals use maladaptive coping responses (e.g., poor emotion regulation strategies) in the face of stressful life events, especially in concert with existing personal vulnerabilities and IPA histories, these external stressors can trigger additional stress within the couple (e.g., distancing and ostracism). This internal stress is posited to deplete existing coping resources at the individual and dyadic levels and place couples at risk for aggressive interactional styles. The sparse research available on these processes within the stress-IPA literature suggest preliminary support for this approach: highly stressed women with poor emotion regulation skills and a tendency to use conflict escalation strategies showed the highest levels of IPA perpetration [15]; undergraduates high in stressful personal problems and an attachment style indicating an avoidant response style reported higher levels of IPA perpetration [12]; and among community couples, maladaptive relational styles mediated the association between perceived stress and sexual coercion [28]. Thus, these results suggest that maladaptive regulatory skills deployed during stressful contexts increase the risk of IPA perpetration.

Only two studies have examined I³ “perfect storm” conditions in the context of the stress-IPA association. Hellmuth and McNulty [18] assessed 169 couples over their first four years of marriage. Risk for IPA was highest among couples reporting higher levels of stress and negative interactions (high instigation), high levels of neuroticism (high impellance), and poor problem solving skills (low inhibition). As noted by the authors, while neuroticism may contribute to IPA via the impelling effects of anger and negative affect, it is also possible that individuals high in neuroticism have impaired self-regulatory processes. Similarly, Finkel et al. [29] assessed changes in IPA perpetration over a 6-month period in a newlywed sample. Participants reported perpetrating more IPA when partner neuroticism (labeled as an instigator) and dispositional anger (impellor) were strong, and psychosocial stress was high (conceptualized as a disinhibitor).

Future Research Directions Regarding Stress and IPA: The Role of Heavy Drinking

Research investigating factors that moderate the association between stress and IPA is relatively limited in both number and scope. For example, there is precious little research in this area examining one of the most consistent predictors of IPA: alcohol intoxication. People drink alcohol in response to stressful events. Tension reduction and stress-response dampening models, which generally posit that alcohol reduces stress, have received considerable empirical support [30]. However, support for the notion that alcohol intoxication invariably decreases stress is equivocal [31,32], leading to the advancement of other models that may explain these contradictory findings. For example, Sayette’s appraisal-disruption model [31] purports that effects of alcohol on stress depend upon the temporal relationship between alcohol consumption and exposure to stress-producing cues. When alcohol consumption precedes exposure to stress-inducing cues, alcohol disrupts initial appraisal of these cues and, consequently results in stress reduction. However, when exposure to stress-inducing cues precedes alcohol consumption, encoding of threat-related information is not impaired and alcohol is posited to increase stress. Consistent with this view, the attention-allocation model of alcohol myopia theory [33,34] posits that acute alcohol intoxication impairs controlled cognitive processing which, in turn, restricts the range of internal and external cues that can be perceived and processed by the imbiber. Consequently, attention resources are allocated to cues that are most salient in a given situation. When stress-inducing cues are salient, alcohol-induced myopia is likely focused on these cues and exacerbates stress.

Thus, it is clear that the use of alcohol as a coping response to “self-medicate” acute stress does not always lead to the desired outcome. And, in addition to potentially exacerbating stress, heavy alcohol use heightens risk for myriad negative outcomes. For example, acute alcohol intoxication exacerbates relationship conflict [35]. This effect is particularly relevant when husbands’ and wives’ heavy drinking patterns are discrepant, as such couples are more likely to report decreased marital satisfaction over time that may ultimately lead to relationship dissolution [36]. Additionally, research indicates that both partners’ alcohol use independently predicts the frequency of each partner’s physical IPA perpetration, and alcohol use by both partners interacts to predict men’s IPA perpetration [36]. Together, these results suggest the need for more focused research on alcohol use as a consequence of stress and the effects of heavy drinking on the dynamics of close relationships.

Conclusion

As noted by relationship scholars [38], contemporary Americans look to marriage and close relationships to fulfill rather lofty individual goals related to personal growth and self-actualization. To make this version of close relationships work effectively, it requires a high and consistent investment of time, energy, and relational skill to achieve and maintain such a deep emotional bond. Unfortunately, research indicates that couples are more stressed today than in previous eras [39,40], especially in the form of minor daily life hassles and annoyances (e.g., work-life balance issues, financial concerns). The research reviewed in this paper suggests that the experience of stress is linearly related to the perpetration of IPA, although the nature of this association is more complex than this simple correlation would indicate. As informed by both stress-vulnerability models [2] and the I³ Model [22], some stressful events can themselves be aggression-provoking (e.g., IPA victimization), while others interact with (a) personal vulnerabilities that promote an urge to aggress, and (b) deficiencies in the ability to regulate emotional responses and/or effectively problem-solve within the dyad.

Highlights.

• Stress is associated with intimate partner aggression (IPA) perpetration.

• Stress interacts with individual vulnerabilities to increase IPA perpetration risk.

• A variety of situational and dispositional factors moderate the stress-IPA association.

• We discuss emerging models of this association and discuss future research recommendations.