Romantic Love and Sleep Variations: Potential Proximate Mechanisms and Evolutionary Functions

Abstract

This article provides a narrative review of what is known about romantic love and sleep variations and provides possible explanations for the association. Romantic love and sleep are described using a comprehensive, unifying framework advocated by Tinbergen. We summarise the findings of studies investigating the relationship between romantic love and sleep. Sleep variations are associated with romantic love in adolescents and young adults. We then detail some proximate mechanisms that may contribute to sleep variations in people experiencing romantic love before considering potential evolutionary functions of sleep variations in people experiencing romantic love. The relationship between symptoms of psychopathology and sleep variations in people experiencing romantic love is described. With the current state of knowledge, it is not possible to determine whether sleep variations associated with romantic love are adaptations or by-products of romantic love. We conclude by proposing areas for future research.

Romantic love evolved by co-opting mother-infant bonding

“…While substantial differences exist between romantic love and mother-infant bonding in some respects, such as the substantial lateralization of neural activity in mother-infant bonding ( Rigo et al, 2019 ; Shih et al, 2022 ), the similarities are consistent with the theory of co-opting mother-infant bonding in the evolutionary history of romantic love. Activation of these areas is likely to have substantial impacts upon behavior above and beyond simply those associated with attraction and the focus of energies on a preferred romantic partner (e.g., affecting sleep and mood; see Bode and Kuula, 2021 ). Fisher (1998 , 2000) and Fisher et al (2002 , 2006) contend that romantic love is the result of activation of a dopaminergic system.…”

Why are depression symptoms scores greater in people experiencing romantic love?

“…The reference to "emotional turmoil" could have biased the sample and inflated the depression symptoms scores in adolescents self-reporting romantic love. We also note that shorter sleep duration is associated with romantic love in adolescents, but not young adults (Bode & Kuula 2021). As a result, our data, which used an adolescent sample, may be more likely to have romantic lovers endorsing symptoms of depression associated with sleep disturbance, fatigue, and tiredness, than may be the case in older samples.…”

“…Additionally, crying can occur in moments of happiness (Avery, 1983;Feldman, 1956;Weiss, 1952)) or during or following sex (Burri & Spector, 2011) which are increased in people experiencing romantic love with their partner. Romantic love may also negatively interfere with sleep (see Bode & Kuula, 2021 for review), which can result in people endorsing depression symptoms in some measures of depression (e.g., BDI, BDI-II), such as sleep changes, tiredness, or fatigue.…”

“…It will also be necessary to gauge whether concentration difficulties are a result of obsessive thinking or not, and if crying is caused by happiness in some people. The role of sleep variations in people, especially adolescents, experiencing romantic love, should also be investigated as a contributor to increased depression symptom scores (see Bode & Kuula, 2021 for review and discussion).…”

The Theory of Co-opting Mother-infant Bonding Informs a New Approach to the Science of Romantic Love (Published in Frontiers in Psychology: https://www.frontiersin.org/articles/10.3389/fpsyg.2023.1176067/full)

“…While substantial differences exist between romantic love and mother-infant bonding in some respects, such as the substantial lateralization of neural activity in mother-infant bonding (Rigo et al, 2019;Shih et al, 2022), the similarities are consistent with the theory of co-opting mother-infant bonding in the evolutionary history of romantic love. Activation of these areas is likely to have substantial impacts upon behavior above and beyond simply those associated with attraction and the focus of energies on a preferred romantic partner (e.g., affecting sleep and mood; see Bode & Kuula, 2021). However, romantic love may not have exclusively co-opted the dopaminergic system from mother-infant bonding, and it may, instead, have been partially incorporated from a pre-existing courtship attraction system.…”