Relationships can be both immensely rewarding and interpersonally challenging. From health to wealth and feelings to finances, reasonable minds can disagree on a wide variety of topics, and conflict may happen as a result.

Some people find themselves more prone to arguments later in the evening when they are tired and irritable—which can lead to an emotionally unhealthy end of the day for both partners. It may be helpful, though, to avoid going to bed angry. Research explains why.

Angela M. Hicks and Lisa M. Diamond investigated the interplay between attachment style, conflict, and reactivity in a piece entitled “Don’t Go to Bed Angry.” [i] They explain that attachment theory suggests that differences in early relationship histories, especially stress‐alleviating interactions with a caregiver, can lead to individual differences in capacities and strategies to regulate individual emotional states, some of which may continue into adulthood. High attachment avoidance is often linked with blunted emotion, attributed to the tendency to avoid affectively charged stimuli.

How does a partner’s attachment style impact present relational functioning? Hicks and Diamond note that people who are high in attachment anxiety have a higher degree of sensitivity and responses to negative events, leading to heightened negative affect and a sharper memory for emotionally significant events.

These different patterns of processing and responding are linked with multiple aspects of relationship behavior and functioning including provision and support seeking, regular sharing of life events, and response to relationship conflict. The key for couples is to navigate attachment style proclivities, ideally with knowledge of a partner’s “triggers” and past experiences.

Studying a group of cohabiting couples, Hicks and Diamond examined the associations between what they defined as “naturally occurring couple conflict,” which they evaluated through end-of-day diaries, and ratings the following morning on sleep disruptions, negative affect, and measure of awakening cortisol response. Among their physiological findings, they found that the morning after heightened quarreling, low-avoidant individuals exhibited heightened negative affect, but high-avoidant individuals experienced lower negative affect.

They also found that more quarreling was linked with more sleep disruptions overall, although this relationship was significantly stronger among individuals with high attachment anxiety, and weaker among individuals with high attachment avoidance.

However we view it, a "conflict hangover" the morning after a night of arguing can negatively impact the entire day. Considering the interplay between sleep and anger, one of the best approaches to avoiding morning after-conflict hangovers could be to set communication ground rules early in a relationship. Here are a few ideas.

References

[i] Hicks, Angela M., and Lisa M. Diamond. 2011. “Don’t Go to Bed Angry: Attachment, Conflict, and Affective and Physiological Reactivity.” Personal Relationships 18 (2): 266–84. doi:10.1111/j.1475-6811.2011.01355.x.