Host-microbial crosstalk relies on "tuft" love.

How commensals influence intestinal immunity is incompletely understood. In this issue of Immunity, Eshleman et al. demonstrate that microbiota-derived butyrate restrains tuft cell development via HDAC3 modulation in intestinal epithelial cells, showing how microbial metabolites impact intestinal type 2 immunity.

Development, regeneration and aging: a bizarre love triangle.

The Jacques Monod Conference on 'Growth and regeneration during development and aging' was organized by Claude Desplan and Allison Bardin in May 2023. The conference took place in Roscoff, France, where participants shared recent conceptual advances under the general motto that developmental processes do not end with embryogenesis. The meeting covered various aspects of how development relates to fitness, regeneration and aging across a refreshing diversity of evolutionarily distant organisms.

Six types of loves differentially recruit reward and social cognition brain areas.

Feelings of love are among the most significant human phenomena. Love informs the formation and maintenance of pair bonds, parent-offspring attachments, and influences relationships with others and even nature. However, little is known about the neural mechanisms of love beyond romantic and maternal types. Here, we characterize the brain areas involved in love for six different objects: romantic partner, one's children, friends, strangers, pets, and nature. We used functional magnetic resonance imaging (fMRI) to measure brain activity, while we induced feelings of love using short stories. Our results show that neural activity during a feeling of love depends on its object. Interpersonal love recruited social cognition brain areas in the temporoparietal junction and midline structures significantly more than love for pets or nature. In pet owners, love for pets activated these same regions significantly more than in participants without pets. Love in closer affiliative bonds was associated with significantly stronger and more widespread activation in the brain's reward system than love for strangers, pets, or nature. We suggest that the experience of love is shaped by both biological and cultural factors, originating from fundamental neurobiological mechanisms of attachment.

Tender love and disassembly: How a TLDc domain protein breaks the V-ATPase.

Vacuolar ATPases (V-ATPases, V1 Vo -ATPases) are rotary motor proton pumps that acidify intracellular compartments, and, when localized to the plasma membrane, the extracellular space. V-ATPase is regulated by a unique process referred to as reversible disassembly, wherein V1 -ATPase disengages from Vo proton channel in response to diverse environmental signals. Whereas the disassembly step of this process is ATP dependent, the (re)assembly step is not, but requires the action of a heterotrimeric chaperone referred to as the RAVE complex. Recently, an alternative pathway of holoenzyme disassembly was discovered that involves binding of Oxidation Resistance 1 (Oxr1p), a poorly characterized protein implicated in oxidative stress response. Unlike conventional reversible disassembly, which depends on enzyme activity, Oxr1p induced dissociation can occur in absence of ATP. Yeast Oxr1p belongs to the family of TLDc domain containing proteins that are conserved from yeast to mammals, and have been implicated in V-ATPase function in a variety of tissues. This brief perspective summarizes what we know about the molecular mechanisms governing both reversible (ATP dependent) and Oxr1p driven (ATP independent) V-ATPase dissociation into autoinhibited V1 and Vo subcomplexes.

Triggers for mother love.

Previous studies showed that baby monkeys separated from their mothers develop strong and lasting attachments to inanimate surrogate mothers, but only if the surrogate has a soft texture; soft texture is more important for the infant's attachment than is the provision of milk. Here I report that postpartum female monkeys also form strong and persistent attachments to inanimate surrogate infants, that the template for triggering maternal attachment is also tactile, and that even a brief period of attachment formation can dominate visual and auditory cues indicating a more appropriate target.

Experienced Love: An Empirical Account.

This article presents new evidence on the prevalence, dynamics, and hedonic correlates of experienced love from data describing the emotion, well-being, and time use of a diverse sample of 3,867 U.S. adults every half hour for 10 days (N = 1.12 million) supplemented by a hedonic snapshot of an additional 7,255 adults. The findings allude to the seemingly functional and adaptive nature of love and to similarities across binary gender-men and women reported comparable degrees of (passionate) partner love overall, elevated partner love after prolonged same-day separations, substantially elevated well-being in love's presence, and reduced (but not extinguished) partner love in mature marital cohorts. The gender differences that were found-women reported more child love than men, and men exhibited a less pronounced reduction in partner love across cohorts-are also consistent with functional accounts of love that recognize the varying role of men and women in the formation and sustenance of relationships.

Daily dynamics of feeling loved by parents and their prospective implications for adolescent flourishing.

Feeling loved by one's caregiver is essential for individual flourishing (i.e., high levels of psychological well-being in multiple dimensions). Although similar constructs are found to benefit adolescent well-being, research that directly tests parental love as a feeling from the recipient's perspective is rare. Historically, parental love has been measured using single-assessment methods and assumed to be a stable, trait-like characteristic; yet, like any feeling, it may fluctuate in meaningful ways on a day-to-day basis-the implications of which are unknown. Using a sample of 150 adolescents (59.3% female; ages 14-16), this study estimated level (person's mean level across days) and instability (fluctuations across days) of feeling loved by a caregiver across 21 days for each adolescent, and then examined their prospective effects on adolescent flourishing 1 year later. After controlling for demographics (adolescent age, gender, family income, and parent's sex) and variable baseline levels, feeling more loved by one's caregiver in daily life significantly predicted higher levels of flourishing in two global measures 1 year later. Moreover, level and instability of feeling loved by one's caregiver played different roles for different dimensions of flourishing: higher levels significantly predicted higher levels of autonomy, purpose in life, and personal growth, whereas higher instability significantly predicted lower levels of positive relations with others and environmental mastery. Findings emphasized the importance of considering daily dynamics of feeling loved by one's caregiver and demonstrated that level (of feeling loved) is particularly important for intrapersonal aspects while instability is particularly important for interpersonal aspects of flourishing. RESEARCH HIGHLIGHTS: Adolescents feeling more loved by their caregiver in daily life had higher levels of overall flourishing 1 year later. Level (of feeling loved) is particularly important for intrapersonal aspects of adolescent flourishing, including autonomy, purpose in life, and personal growth. Stability (of feeling loved) is particularly important for interpersonal aspects of adolescent flourishing, including positive relations with others and environmental mastery.

Feeling loved in mixed-gender adolescent romantic relationships in the face of daily stress and support: A dyadic diary study.

A profound developmental experience is the emergence of adolescent romantic relationships and first feelings of love. However, the daily nature of feeling loved in adolescents' everyday lives is poorly understood. We investigated how daily stress severity was associated with adolescents' levels of feeling loved and whether romantic partner support moderated these associations. Furthermore, we investigated this for non-interpersonal and interpersonal stressors. N = 97 mixed-gender adolescent romantic couples (age M = 16.38, SD = 1.02) from an ethnically diverse sample (42.2% Hispanic/Latino/a/x, 44.7% White) participated in dyadic diary assessments twice a week for 12 consecutive weeks. Both partners independently completed open-ended questions about a daily stressor, indicating stress severity, perceived partner support, and feeling loved. Daily stressors were coded for non-interpersonal and various types of interpersonal stressors. Results from the dyadic multilevel model showed that days with lower than average support from a romantic partner amplify the adverse effects of stress severity on feeling loved, especially when the partner is involved in the stressor. We discuss the spillover of stress in romantic relationships and the stress-buffering functions of adolescent romantic partner support. Adolescent romantic partners are potentially essential regulators of stress, increasing adolescents' feelings of love. RESEARCH HIGHLIGHTS: Romantic love is central in adolescents' lives; we showed that adolescents generally feel loved by romantic partners. Feeling loved fluctuates daily as adolescents feel less loved on stressful days. However, when adolescents perceive their partner as supportive, there is no association between stress and feeling loved. Partner support is protective for feeling loved. The current study provides essential insights into when adolescents and why adolescents feel loved.

Parental expressions of love in Chinese American immigrant families: Implications for children's attachment security.

Harlow's seminal work on the nature of attachment focused on the importance of warm, responsive, and loving relationships in children's healthy development. While the need for love and care is arguably universal, the ways in which these emotions are expressed can vary across cultural contexts. We examined how Chinese American parents' expressions of love were associated with children's attachment security. A total of 110 Chinese American immigrant parent-child dyads (children 7-11 years old, 49% girls) participated in 3-min conversations in which parents were instructed to communicate love and care. Proposition-level analyses in speech (total 8825 propositions) identified three types of affection: training (guan and chiao shun); relational affection (qin); and validation (acceptance and encouragement of child's own expression of emotion, thoughts, and behaviors). Higher training was observed in parents with lower American orientation and lower income. Higher relational affection was observed in parents with lower income. Higher validation was observed in parents with higher income. Using path analyses, training and validation were found to be positively associated with children's attachment security beyond parenting styles. Effects of parents' relational affection were moderated by children's American orientation. Results demonstrate how immigrant parents draw on multiple cultural scripts to express love and care. These findings expand traditional concepts of parental love in immigrant families and illustrate how bicultural expressions of love can shape attachment security in middle childhood. A video abstract of this article can be viewed at https://youtu.be/HqUfIDxkFsE RESEARCH HIGHLIGHTS: Analyses of parent-child discussions identified three parental affection styles (i.e., training, relational affection, and validation) as expressions of love and care in Chinese American immigrant families. Training and validation were positively associated with children's attachment security. Relational affection was associated with lower attachment security for children with higher American cultural orientation, suggesting the effects of parent-child expressions of love are shaped by acculturation.

Love on the developing brain: Maternal sensitivity and infants' neural responses to emotion in the dorsolateral prefrontal cortex.

Infancy is a sensitive period of development, during which experiences of parental care are particularly important for shaping the developing brain. In a longitudinal study of N = 95 mothers and infants, we examined links between caregiving behavior (maternal sensitivity observed during a mother-infant free-play) and infants' neural response to emotion (happy, angry, and fearful faces) at 5 and 7 months of age. Neural activity was assessed using functional Near-Infrared Spectroscopy (fNIRS) in the dorsolateral prefrontal cortex (dlPFC), a region involved in cognitive control and emotion regulation. Maternal sensitivity was positively correlated with infants' neural responses to happy faces in the bilateral dlPFC and was associated with relative increases in such responses from 5 to 7 months. Multilevel analyses revealed caregiving-related individual differences in infants' neural responses to happy compared to fearful faces in the bilateral dlPFC, as well as other brain regions. We suggest that variability in dlPFC responses to emotion in the developing brain may be one correlate of early experiences of caregiving, with implications for social-emotional functioning and self-regulation. RESEARCH HIGHLIGHTS: Infancy is a sensitive period of brain development, during which experiences with caregivers are especially important. This study examined links between sensitive maternal care and infants' neural responses to emotion at 5-7 months of age, using functional near-infrared spectroscopy (fNIRS). Experiences of sensitive care were associated with infants' neural responses to emotion-particularly happy faces-in the dorsolateral prefrontal cortex.

Minor-Attracted Men's Lived Experiences of Romantic Attraction.

Studies of minor-attracted persons have mainly focused on their sexual attractions, and little is known about their romantic attractions. This online qualitative survey study collected 74 self-identified minor-attracted men's anonymous accounts of romantic attraction to minors. Using reflexive thematic analysis, three themes were identified and interpreted: (1) Falling in Love; (2) Recognizing Limitations to Attraction and Relationship Development; (3) Making Sense and Meaning of Romantic Attraction to Minors. Overall, romantic attraction to minors resembles romantic attraction to adults. Findings have implications for how conceptualization, assessment, and treatment of minor attraction may each consider both sexual and romantic domains.

Romantic Love and Sexual Frequency: Challenging Beliefs.

Common conceptions of romantic love suggest that romantic love is associated with increased sexual activity with more frequent sex in the earlier stages of a romantic relationship. To our knowledge, no studies have investigated individual-level factors and sexual frequency using a validated measure of romantic love. This study tested a number of hypotheses about the factors associated with sexual frequency among 720 sexually active young adults experiencing romantic love from the Romantic Love Survey 2022. We hypothesized that relationship duration, the intensity of romantic love and obsessive thinking about a loved one, commitment, and hypomanic-like features would be associated with sexual frequency. Using hierarchical linear regression, controlling for known covariates, we found no significant associations between any of our variables of interest and the sexual frequency and our entire model of 14 well-reasoned predictors explained only 4.06% of the variation in sexual frequency. The findings are surprising and highlight how little is currently known about sexual activity and sexual desire among individuals experiencing romantic love.

Love Matters: The Effect of Mating Motive on Female Food Choice.

The prevalence of obesity has been increasing globally in recent decades. Behind the phenomenon, high-fat food consumption has been conceived as an important driver. In the current study, we explored whether mating motive caused an effect on female food choice as well as the psychological mechanism underlying it. In Study 1, we recruited 64 participants from a university and asked them to complete a mating prime, after which they would finish a food choice task in which food with different flavors were shown. In Study 2, we replicated Study 1 with a different mating priming method and examined the mediating role of body shaping desire on the relation between mating motive and female food choice. Results showed that: (1) The salience of mating motive decreased female's high-fat food choice but increased male's high-fat food choice; (2) the effect of mating motive in females was robust and more salient for sweet food rather than salty food; and (3) the body shaping desire partially mediated the effect of mating motive on female food choice.

Reproductive Strategies and Romantic Love in Early Modern Europe.

In Western Europe, the Early Modern Period is characterized by the rise of tenderness in romantic relationships and the emergence of companionate marriage. Despite a long research tradition, the origins of these social changes remain elusive. In this paper, we build on recent advances in behavioral sciences, showing that romantic emotional investment, which is more culturally variable than sexual attraction, enhances the cohesion of long-term relationships and increases investment in children. Importantly, this long-term strategy is considered especially advantageous when living standards are high. Here, we investigate the relationship between living standards, the emotional components of love expressed in fiction work, and behavioral outcomes related to pair bonding, such as nuptial and fertility rates. We developed natural language processing measures of "emotional investment" (tenderness) and "attraction" (passion) and computed romantic love in English plays (N = 847) as a ratio between the two. We found that living standards generally predicted and temporally preceded variations of romantic love in the Early Modern Period. Furthermore, romantic love preceded an increase in nuptial rates and a decrease in births per marriage. This suggests that increasing living standards in the Early Modern Period may have contributed to the emergence of modern romantic culture.

Validation of the Short Version (TLS-15) of the Triangular Love Scale (TLS-45) across 37 Languages.

Love is a phenomenon that occurs across the world and affects many aspects of human life, including the choice of, and process of bonding with, a romantic partner. Thus, developing a reliable and valid measure of love experiences is crucial. One of the most popular tools to quantify love is Sternberg's 45-item Triangular Love Scale (TLS-45), which measures three love components: intimacy, passion, and commitment. However, our literature review reveals that most studies (64%) use a broad variety of shortened versions of the TLS-45. Here, aiming to achieve scientific consensus and improve the reliability, comparability, and generalizability of results across studies, we developed a short version of the scale-the TLS-15-comprised of 15 items with 5-point, rather than 9-point, response scales. In Study 1 (N = 7,332), we re-analyzed secondary data from a large-scale multinational study that validated the original TLS-45 to establish whether the scale could be truncated. In Study 2 (N = 307), we provided evidence for the three-factor structure of the TLS-15 and its reliability. Study 3 (N = 413) confirmed convergent validity and test-retest stability of the TLS-15. Study 4 (N = 60,311) presented a large-scale validation across 37 linguistic versions of the TLS-15 on a cross-cultural sample spanning every continent of the globe. The overall results provide support for the reliability, validity, and cross-cultural invariance of the TLS-15, which can be used as a measure of love components-either separately or jointly as a three-factor measure.

Young Love "Locked Down": Adolescent and Young Adult Perspectives on Sexting During the Covid-19 Pandemic in England.

There were limited opportunities for in-person social, intimate, and sexual interactions in England during 2020-2021, due to restrictions imposed by the UK government in response to the Covid-19 pandemic. While previous studies examined the effects of lockdown on intimate relationships, there is less qualitative research regarding young people's perspectives on and experiences of digitally mediated intimacy (sexting) during the period. This paper discusses findings from focus groups with 80 adolescents and interviews with 38 young adults that explored the topic. Analysis identified a normalization of non-consensual distribution of intimate images within adolescent peer culture and a reluctance to report or intervene in response to incidents of non-consensual distribution that are witnessed or experienced. The adolescent girls and young adult women also described other forms of unwanted and invasive image-sharing and requests for images. Young adults held various perspectives on sexting during lockdown, with some describing sexting as unfulfilling and/or "risky" and others sharing experiences of using sexting to generate intimacy and, among some, engaging in unwanted sexting with partners. By considering both adolescent and young adult perspectives obtained through focus groups and interviews, the study highlighted how group-level norms and meanings surrounding the risks and rewards of sexting may be reproduced or reworked as individuals transition from adolescence to young adulthood. The study underscores the need to support adolescents and young adults in cultivating healthy digital sexual cultures and interpersonal relationships.

Being as Having, Loving, and Doing: A Theory of Human Well-Being.

ACADEMIC ABSTRACT: Stronger theory on the nature of human well-being is needed, especially as well-being indicators are increasingly utilized in policy contexts. Building on Erik Allardt, who argued that a theory of well-being is, in essence, a theory of human nature, I propose four modes of existence each capturing one dimension central to human well-being: Having recognizes humans as biological creatures requiring certain material resources for survival. Loving captures human social nature and our dependence on others for well-being. Doing highlights the active and agentic nature of human existence. Being acknowledges humans as experiencing their existence. Each mode of existence gives rise to a few more specific needs, and a full assessment of human well-being requires both subjective and objective indicators tapping into these needs. The proposed theory integrates psychological well-being research with sociological and philosophical traditions and contributes to debates about how the progress of nations and sustainability should be measured. PUBLIC ABSTRACT: Well-being is something we all value individually, and it is also a key political goal. Accordingly, how we define and measure well-being influences what physicians, managers, policy-makers, politicians, and international organizations aim to improve through their work. Better theories of well-being make better measurement of well-being possible, which makes possible more effective and evidence-based advancement of human well-being. In this spirit, the present article argues that there are four fundamental dimensions to human well-being: Having highlights that as biological creatures, we have physical needs, loving highlights human social needs, doing highlights that we are active and agentic beings with goals and strivings, and being highlights that we feel and evaluate our lives. To assess well-being, we need measures tapping into all four of these dimensions. And to assess the sustainability of well-being, we need to examine how to provide well-being for all humanity while remaining within planetary boundaries.