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Romantic partners often share a bed, and researchers have found links between people’s sleep habits and their relationship experiences.
What does your sleep say about the quality of your relationship? In general, people are more satisfied with their relationships if they tend to sleep better. People report sleeping better when they feel close and connected with their romantic partners. They sleep worse after a fight. And now that they've slept poorly? People are more likely to fight with their partners and less likely to resolve the conflict if they slept poorly the prior night.
Does your sleep tell you something about how secure you feel in your relationships? From military vets to college students, people who are anxiously attached tend to get less deep sleep, show brain activation during sleep that is consistent with hyperarousal, have lower sleep efficiency (spend more time awake when they want to be sleeping), and report worse sleep quality.
Feeling lonely? Lonely individuals show worse sleep efficiency, more fragmented sleep, and greater daytime fatigue. And to bring it full circle—people feel report feeling lonelier after sleeping poorly.
What about sleeping in-sync with your partner? In a handful of studies, researchers have found that couples with more concordant sleep, both in terms of overall sleep-wake patterns and number of matched minutes awake throughout the night are more satisfied with their relationships and experience less marital conflict. Those couples who are mismatched in their sleep-wake patterns but are satisfied with their relationships have been shown to be better at flexible and adaptively solving problems in their relationships. In general, though, couples who are mismatched (e.g., a morning person married to an evening person) spend less time in shared activities and have less sex compared to matched couples. For matched couples - morning couples have more sex in the morning and evening couples have more sex in the evening, but their overall sexual frequency doesn’t differ. Sleep concordance may also matter for health - in one study, couples who were more matched in terms of the minutes they were awake and asleep throughout the night had lower blood pressure during the night as well as lower systemic inflammation.
Our sleep may also reveal something about those around us—in the study on sleep and loneliness, people who viewed a video of a sleep-deprived individual (compared to when that person was well-rested) not only rated the sleep-deprived person as lonelier, they actually report feeling lonelier themselves. In couples, people are more satisfied with their relationships if their partner is a good sleeper, and are less empathically accurate after a night when their partner slept poorly.
We spend 1/3 of our lives (approximately) sleeping, and research is increasingly shedding light on how this seemingly solitary experience is in fact closely connected to our social lives.
References
Gunn, H. E., Buysse, D. J., Matthews, K. A., Kline, C. E., Cribbet, M. R., & Troxel, W. M. (2017). Sleep–Wake Concordance in Couples Is Inversely Associated With Cardiovascular Disease Risk Markers. Sleep, 40(1).
Larson, J. H., Crane, D. R., & Smith, C. W. (1991). Morning and night couples: the effect of wake and sleep patterns on marital adjustment. Journal of Marital and Family Therapy, 17(1), 53-65.
Simon, E. B., & Walker, M. P. (2018). Sleep loss causes social withdrawal and loneliness. Nature communications, 9.
Strawbridge, W. J., Shema, S. J., & Roberts, R. E. (2004). Impact of spouses’ sleep problems on partners. Sleep, 27(3), 527-531.
Troxel, W. M. (2010). It’s more than sex: Exploring the dyadic nature of sleep and implications for health. Psychosomatic medicine, 72(6), 578.
Troxel, W. M., & Germain, A. (2011). Insecure attachment is an independent correlate of objective sleep disturbances in military veterans. Sleep medicine, 12(9), 860-865.
