The aim of this study was to determine whether two newly introduced interpersonal emotion regulation strategies in couples predict adjustment symptoms above and beyond established intrapersonal emotion regulation. Furthermore, the dyadic data set allowed for the exploration of possible partner effects of intra- and interpersonal emotion regulation. We investigated three different symptoms of maladjustment: preoccupation (i.e., unwanted repetitive negative thoughts about the stressor); failure to adapt (i.e., problems in daily functioning in response to the stressor), and depressive symptoms.
In general, the results underline the importance of intra-and interpersonal emotion regulation for predicting adjustment symptoms. The beta weights suggest medium effect sizes. Co-brooding—the unwanted repetitive disclosing of negative content to the partner—was a significant predictor of symptoms above and beyond intrapersonal brooding, which was also significantly associated with symptoms. Subtle gender differences could be observed here. In the male sample, co-brooding was significant in all three symptom domains. In contrast, in the female sample co-brooding was only significant above and beyond the other strategies predicting symptoms related to daily functioning (failure to adapt) and for depressive symptoms if controlled for intrapersonal brooding. It is important to note that bivariate correlations of co-brooding with the symptom groups were also significant for women in our sample. However, controlling for an individual’s own co-reappraisal and partner co-reappraisal seemed to be relevant in this case suggesting shared variance.
Co-reappraisal—the attempt to reframe the situation cognitively in conversation with the partner—was associated with less depressive symptoms in the female sample, which was not the case in the male sample. Furthermore, it was predictive for female preoccupation, however only if the effect was not controlled for intrapersonal ruminative brooding. This suggests more overlapping variance of both interpersonal strategies and intrapersonal ruminative brooding in women, which is also reflected in significant bivariate correlation coefficients (see Table 1). In contrast, intra- and interpersonal brooding did not correlate in the male sample; nor did the two interpersonal strategies of co-brooding and co-reappraisal.
Moreover, in this sample, intrapersonal reappraisal was not associated with an individual’s own symptoms or their partner’s symptoms. However, there was one exception. Only one partner effect could be observed; if the female partner reported higher levels of reappraisal, male participants reported less preoccupation. It is important to note that this is controlled for an individual’s own reappraisal and interdependencies in the couple; thus, the partner’s tendency to reappraise was additionally associated with being less preoccupied about the stressful event above and beyond an individual’s own strategies.
In summary, it can be stated that even controlling for intrapersonal strategies, the presented measures of co-brooding and to a lesser extent co-reappraisal are emotion regulation strategies in interactions that are associated with adjustment symptoms and are not mere reflections of intrapersonal processes. The interactive nature of the regulation strategies seems to capture unique variance when it comes to explaining adjustment symptoms after a stressful event. In particular, co-brooding as the unwanted repetitive sharing of negative content with the partner seems to be highly associated with symptoms, especially in male participants. It is important to note, that this relies on a composite score of co-brooding combining the perspectives of both partners. So if both partners report this kind of interactions in the couple this is reflecting a maladaptive way of dealing together with negative content.
Further longitudinal prospective research is needed to explore whether co-brooding actually represents a pre-existing background risk factor that predicts the development of symptoms over time. The results of this study could also be interpreted in such a way that if (male) partners rely on co-brooding in the couple as an interpersonal emotion regulation strategy, it is an epiphenomenon of high symptom levels. Similar discussions have been taking place in the field of intrapersonal ruminative brooding, leading to mixed results . Theoretically, rumination is expected to represent a risk factor that prolongs and intensifies depressive symptoms, maintains clinical episodes of depression, and increases the likelihood of a new episode . With due caution in terms of cross-sectional data interpretation, the results support the view of interpersonal co-brooding as possibly intensifying depressed mood and adjustment disorder symptoms. Co-brooding thus seems to be relevant in the clinical presentation of adults adjusting to a stressful event and deserves further research. Recent research on intrapersonal repetitive negative thoughts underlines the potential stress-inflating and thus health-harming effect of being stuck in ruminative cycles and worries also pointing on the documented effects on physiological functioning . Co-brooding could in this context be seen as doubly harmful, as it not only undermines individual coping attempts but also includes interpersonal processes that possibly reduce relationship quality. Relationship quality in turn is known to be an important factor in mental and even physical health; a recent study showed over a period of 10 years significant associations between perceived responsiveness and a physiological correlate of stress, the cortisol level . Interestingly enough, the associations were mediated by negative affect, which supports the socio-affective pathway hypothesis of interpersonal emotion regulation . In this study, the measure of co-brooding already included the theoretically expected reduction of relationship quality. Further research is needed to get a better understanding of the different pathways of co-brooding on the intra- and interpersonal level.
In the literature, there is evidence that adaptive emotion regulation strategies, at least as measured by retrospective self-reports, tend to have a lower degree of association with mental health outcomes than maladaptive strategies . This can also be observed in this study; only a partner effect of reappraisal could be observed in addition to actor effects of co-reappraisal in women. It has been suggested that the lack of predictive power of adaptive strategies is due to more contextual variability of adaptive strategies as opposed to maladaptive strategies . Recent research on reappraisal underlines this notion; in certain situations, reappraisal is not the most adaptive regulation strategy, like, for example, late in the emotion generation process when the intensity of the affective state is very high . The trait-like measurement of reappraisal thus might be problematic as the fit between regulation strategy and context is neglected. This might be particularly true in the context of stress response after severe stressful experiences that tend to induce intense emotions. Further research, including taking within-person variability in different contexts into account, is needed.
When controlling for interdependencies in the couple, there are almost no partner effects. Against the possible expectation that interactive emotion regulation undertaken with the partner should show more partner effects, the only observed partner effect is that of intrapersonal reappraisal of the female partner. This is in line with the notion that when adequate social support and co-regulation is needed, an individual’s own regulation resources are of great importance . Empathic reactions include empathic sharing of the affective state of the interaction partner; these reactions challenge the emotion regulation resources of the partner as well. They cannot be regulated in a functional way, and the listener will have difficulties showing empathic concern and providing responsive and supportive reactions (see  for a discussion of the neural basis of these processes). Therefore, the results could possibly be interpreted as pointing to the importance of adaptive emotion regulation in the co-regulating partner when it comes to coping together with stressful events. One could argue that well-regulated partners manage best the challenge of sharing empathically negative affect without suffering too much contagion of negative mood with the risk negative reciprocity. Furthermore, first studies hint to the relevance of considering an interplay of intra- and interpersonal emotion regulation strategies .
We found gender differences in this study; for example, women’s intra- and interpersonal emotion regulation strategies were more interrelated compared to those of the male sample. Furthermore, co-reappraisal played a more important role for women, while it was not of significance for men. In the literature, sex differences in coping have been extensively reported; for example, LK Tamres, D Janicki and VS Helgeson  concluded in their meta-analysis that the most pronounced sex effect was that women rely more on coping strategies which include verbal expressions to others or the self. An example of these strategies is rumination, which supposedly leads to chronic strain and has been theoretically introduced as a typical “female” phenomenon . In the context of the stress-generation hypothesis in depression, these vicious circles have been interpreted as typically being associated with being female, with dispositional differences, and with role constraints . This tendency to verbalize stress suggests that women rely more on interpersonal emotion regulation that do men; as expected, our data revealed baseline differences in interpersonal strategies and brooding. The amount of disclosure of personal content is very different in relationships; typically, women disclose more . Co-reappraisal reflects the motive for cognitive change in the disclosure process; this might influence the quality of female disclosure in the couple relationship in a way that makes it more accessible for the male partner. This in turn might be associated with more responsive reactions by the male partner. Earlier studies show that women are more susceptible to perceived responsiveness  and criticism  in the relationship. It would be interesting to investigate this pathway in further explorations of co-reappraisal. However, in general, our data did not show profound sex differences regarding interpersonal emotion regulation, and there were no harmful partner effects on women or on men.
This study has certain limitations that must be noted: the sample is a convenience online sample and stressors as well as symptoms are self-reported. Even though doubt about how representative online studies can possibly be can be dispelled , it would be interesting to recruit a clinical sample and include a clinical assessment of adjustment disorder in future studies on interpersonal emotion regulation. Furthermore, these are cross-sectional data with all their limitations. However, as the research area is relatively new, the results of this cross-sectional study might encourage more elaborate studies. The use of the composite measure of co-brooding that includes both views on the process—the perspective of the individual and the partner’s perspective—might strengthen the results as, for example, the effects of social desirability should be reduced and common critic on self-report of couple processes addressed. Interestingly enough, while adding up self- and partner reports of co-brooding led to a satisfying internal consistency suggesting that both partners’ views were highly interrelated, there was a significant rater discrepancy in terms of co-reappraisal.