Sexually Dimorphic Control of Parenting Behavior by the Medial Amygdala.

Social behaviors, including behaviors directed toward young offspring, exhibit striking sex differences. Understanding how these sexually dimorphic behaviors are regulated at the level of circuits and transcriptomes will provide insights into neural mechanisms of sex-specific behaviors. Here, we uncover a sexually dimorphic role of the medial amygdala (MeA) in governing parental and infanticidal behaviors. Contrary to traditional views, activation of GABAergic neurons in the MeA promotes parental behavior in females, while activation of this population in males differentially promotes parental versus infanticidal behavior in an activity-level-dependent manner. Through single-cell transcriptomic analysis, we found that molecular sex differences in the MeA are specifically represented in GABAergic neurons. Collectively, these results establish crucial roles for the MeA as a key node in the neural circuitry underlying pup-directed behaviors and provide important insight into the connection between sex differences across transcriptomes, cells, and circuits in regulating sexually dimorphic behavior.

Multisensory Logic of Infant-Directed Aggression by Males.

Newborn mice emit signals that promote parenting from mothers and fathers but trigger aggressive responses from virgin males. Although pup-directed attacks by males require vomeronasal function, the specific infant cues that elicit this behavior are unknown. We developed a behavioral paradigm based on reconstituted pup cues and showed that discrete infant morphological features combined with salivary chemosignals elicit robust male aggression. Seven vomeronasal receptors were identified based on infant-mediated activity, and the involvement of two receptors, Vmn2r65 and Vmn2r88, in infant-directed aggression was demonstrated by genetic deletion. Using the activation of these receptors as readouts for biochemical fractionation, we isolated two pheromonal compounds, the submandibular gland protein C and hemoglobins. Unexpectedly, none of the identified vomeronasal receptors and associated cues were specific to pups. Thus, infant-mediated aggression by virgin males relies on the recognition of pup's physical traits in addition to parental and infant chemical cues.

The Neurobiology of Parenting and Infant-Evoked Aggression.

Parenting behavior comprises a variety of adult-infant and adult-adult interactions across multiple timescales that require an extensive reorganization of individual priorities and physiology. The state transition from non-parent to parent is facilitated by combinatorial hormone action on specific cell types that are integrated throughout interconnected and brain-wide neuronal circuits. In this review we take a comprehensive approach to integrate historical and current literature on each of these topics across multiple species, with a focus on rodents. New and emerging molecular, circuit based and computational technologies have recently been used to address outstanding gaps in our current framework of knowledge on infant-mediated behavior, mainly in murine models. This work is raising fundamental questions about the interplay between instinctive and learned components of parenting and the mutual regulation of parenting and anti-parenting behaviors in health and disease. Whenever possible, we point to how these technologies have helped gain novel insights, while opening new avenues of research into studies of parenting. We hope this review will serve as an introduction for those new to the field, a comprehensive resource for those already studying parenting, and a guidepost for designing future studies.

Economic mobility and parents' opportunity hoarding.

Creating opportunities for people to achieve socioeconomic mobility is a widely shared societal goal. Paradoxically, however, achieving this goal can pose a threat to high-socioeconomic-status (SES) people as they look to maintain their privileged positions in society for both them and their children. Two studies evaluate whether this threat manifests as "opportunity hoarding" in which high-SES parents adopt attitudes and behaviors aimed at shoring up their families' access to valuable educational and economic resources. The current paper provides converging evidence for this hypothesis across two studies conducted with 2,557 American parents. An initial correlational study demonstrated that believing that socioeconomic mobility is possible was associated with high-SES parents being more inclined to attempt to secure valuable educational and economic resources for their children, even when doing so came at the cost of low-SES families. Specifically, high-SES parents with stronger beliefs in socioeconomic mobility exhibited decreased support for redistributive policies and viewed engaging in discrete behaviors that would unfairly advantage their children (e.g., allowing them to misrepresent their identities on school and job applications) as more acceptable relative to both low-SES parents with similar beliefs and high-SES parents who were less optimistic about socioeconomic mobility. A subsequent experimental study established these relationships causally by comparing parents' responses to different types of socioeconomic mobility. Together, the current findings merge insights across psychology and economics to deepen understandings of the processes through which societal inequities emerge and persist, especially during times of apparently abundant opportunity.

Testosterone's role in modulating human behaviors relevant to mating and parenting.

Testosterone (T) is linked to human mating and parenting. Here, we comprehensively reviewed evidence on whether, in men and women, (1) basal T levels are related to mating and parenting behaviors, (2) T responds to reproduction-relevant cues, (3) acute changes in T map onto subsequent mating and parenting behaviors, and (4) single-dose exogenous T administration causally affects mating and parenting behaviors. We examined whether the available evidence supports trade-off interpretations of T's adaptive function whereby high T levels correspond to greater mating/reproductive effort and competition and low T levels to greater parenting effort and nurturance. We found mixed support for trade-off hypotheses, suggesting that T's function in modulating human mating and parenting might be more nuanced and highly dependent on context and individual trait differences. Results were largely similar for men and women, although studies with women were scarcer than those with men for most behaviors we reviewed.

Cortical volume reductions in men transitioning to first-time fatherhood reflect both parenting engagement and mental health risk.

Perinatal reductions in gray matter volume have been observed in human mothers transitioning to parenthood, with preliminary evidence for similar changes in fathers. These reductions have been theorized to support adaptation to parenting, but greater investigation is needed. We scanned 38 first-time fathers during their partner's pregnancy and again after 6 months postpartum, and collected self-report data prenatally and 3, 6, and 12 months postpartum. Significant gray matter volume reductions were observed across the entire cortex but not the subcortex. Fathers who reported stronger prenatal bonding with the unborn infant, and planned to take more time off from work after birth, subsequently showed larger cortical volume decreases. Larger reductions in gray matter volume also emerged among fathers who reported stronger postpartum bonding with the infant, lower parenting stress, and more time spent with their infant. Larger volume reductions predicted more postpartum sleep problems and higher levels of postpartum depression, anxiety, and psychological distress, controlling for prenatal sleep and mental health. Volume reductions were smaller among fathers whose infants were older at the postpartum scan, indicating potential rebound. These results suggest that perinatal gray matter volume reductions might reflect not only greater parenting engagement but also increased mental health risk in new fathers.

Parenting links to parent-child interbrain synchrony: a real-time fNIRS hyperscanning study.

Parent-child interaction is crucial for children's cognitive and affective development. While bio-synchrony models propose that parenting influences interbrain synchrony during interpersonal interaction, the brain-to-brain mechanisms underlying real-time parent-child interactions remain largely understudied. Using functional near-infrared spectroscopy, we investigated interbrain synchrony in 88 parent-child dyads (Mage children = 8.07, 42.0% girls) during a collaborative task (the Etch-a-Sketch, a joint drawing task). Our findings revealed increased interbrain synchrony in the dorsolateral prefrontal cortex and temporo-parietal areas during interactive, collaborative sessions compared to non-interactive, resting sessions. Linear regression analysis demonstrated that interbrain synchrony in the left temporoparietal junction was associated with enhanced dyadic collaboration, shared positive affect, parental autonomy support, and parental emotional warmth. These associations remained significant after controlling for demographic variables including child age, child gender, and parent gender. Additionally, differences between fathers and mothers were observed. These results highlight the significant association between brain-to-brain synchrony in parent-child dyads, the quality of the parent-child relationship, and supportive parenting behaviors. Interbrain synchrony may serve as a neurobiological marker of real-time parent-child interaction, potentially underscoring the pivotal role of supportive parenting in shaping these interbrain synchrony mechanisms.

Reimagining possibilities: the journey of a PhD parent.

In this commentary, I discuss my non-traditional pathway to a PhD, a late-bloomer's account of balancing a young family and PhD studies, a guide for those contemplating the same path.

Associations between Parenting and Cognitive and Language Abilities at 2 Years of Age Depend on Prenatal Exposure to Disadvantage.

OBJECTIVE: To investigate whether parenting or neonatal brain volumes mediate associations between prenatal social disadvantage (PSD) and cognitive/language abilities and whether these mechanisms vary by level of disadvantage. STUDY DESIGN: Pregnant women were recruited prospectively from obstetric clinics in St Louis, Missouri. PSD encompassed access to social (eg, education) and material (eg, income to needs, health insurance, area deprivation, and nutrition) resources during pregnancy. Neonates underwent brain magnetic resonance imaging. Mother-child dyads (n = 202) returned at age 1 year for parenting observations and at age 2 years for cognition/language assessments (Bayley Scales of Infant and Toddler Development, Third Edition). Generalized additive and mediation models tested hypotheses. RESULTS: Greater PSD associated nonlinearly with poorer cognitive/language scores. Associations between parenting and cognition/language were moderated by disadvantage, such that supportive and nonsupportive parenting behaviors related only to cognition/language in children with lesser PSD. Parenting mediation effects differed by level of disadvantage: both supportive and nonsupportive parenting mediated PSD-cognition/language associations in children with lesser disadvantage, but not in children with greater disadvantage. PSD-associated reductions in neonatal subcortical grey matter (ß = 0.19; q = 0.03), white matter (ß = 0.23; q = 0.02), and total brain volume (ß = 0.18; q = 0.03) were associated with lower cognition, but did not mediate the associations between PSD and cognition. CONCLUSIONS: Parenting moderates and mediates associations between PSD and early cognition and language, but only in families with less social disadvantage. These findings, although correlational, suggest that there may be a critical threshold of disadvantage, below which mediating or moderating factors become less effective, highlighting the importance of reducing disadvantage as primary prevention.

Reported Intergenerational Transmission of Parent Weight Talk and Links with Child Health and Wellbeing.

OBJECTIVES: To examine if intergenerational transmission of parent weight talk occurs, the contextual factors prompting weight talk, and whether parent weight talk is associated with child weight, dietary intake, psychosocial outcomes, and food parenting practices. STUDY DESIGN: Children aged 5-9 years and their families (n = 1307) from 6 racial and ethnic groups (African-American, Hispanic, Hmong, Native American, Somali/Ethiopian, White) were recruited for a longitudinal cohort study through primary care clinics in Minneapolis/St. Paul, Minnesota from 2016 through 2019. Parents filled out surveys at 2 time points, 18 months apart. Adjusted regression models examined associations of interest. RESULTS: Intergenerational transmission of parent weight talk was observed. In addition, significant associations were found between parent engagement in weight talk and higher weight status and poorer psychosocial outcomes in children 18 months later. Parent engagement in weight talk was also associated with more restrictive food parenting practices 18 months later. CONCLUSIONS: Parents' exposure to weight talk as children increased the likelihood of engaging in weight talk with their own children and had harmful associations over time with parent restrictive feeding practices, child weight, and psychosocial wellbeing in children. Health care providers may want to consider both modeling positive health-focused conversations and educating parents about the potential harmful and long-lasting consequences of engaging in weight talk with their children.

Executive Function in Preschool Children with Congenital Heart Disease and Controls: The Role of a Cognitively Stimulating Home Environment.

OBJECTIVE: To assess the relationships between (1) environmental and demographic factors and executive function (EF) in preschool children with congenital heart disease (CHD) and controls and (2) clinical and surgical risk factors and EF in preschool children with CHD. STUDY DESIGN: At 4-6 years of age, parents of children with CHD (n = 51) and controls (n = 124) completed the Behavior Rating Inventory of Executive Function, Preschool Version questionnaire and the Cognitively Stimulating Parenting Scale (CSPS). Multivariable general linear modeling assessed the relationship between Behavior Rating Inventory of Executive Function, Preschool Version composite scores (Inhibitory Self-Control Index [ISCI], Flexibility Index [FI], and Emergent Metacognition Index [EMI]) and group (CHD/control), sex, age at assessment, gestational age, Index of Multiple Deprivation, and CSPS scores. The relationships between CHD type, surgical factors, and brain magnetic resonance imaging injury rating and ISCI, FI, and EMI scores were assessed. RESULTS: The presence of CHD, age at assessment, sex, and Index of Multiple Deprivation were not associated with EF scores. Lower gestational age was associated with greater ISCI and FI scores, and age at assessment was associated with lower FI scores. Group significantly moderated the relationship between CSPS and EF, such that CSPS significantly predicted EF in children with CHD (ISCI: P = .0004; FI: P = .0015; EMI: P = .0004) but not controls (ISCI: P = .2727; FI: P = .6185; EMI: P = .3332). There were no significant relationships between EF scores and surgical factors, CHD type, or brain magnetic resonance imaging injury rating. CONCLUSIONS: Supporting parents to provide a cognitively stimulating home environment may improve EF in children with CHD. The home and parenting environment should be considered when designing intervention studies aimed at improving EF in this patient group.

Transgender persons' view on previous fertility decision-making and current infertility: a qualitative study.

STUDY QUESTION: How do adult transgender and gender diverse (TGD) people, who are infertile due to prior gender-affirming treatment, view their current infertility and their reproductive decisions made in the past? SUMMARY ANSWER: In a time where sterilization was mandatory, transgender adolescents prioritized gender-affirming treatment over their future fertility and would make the same choice today despite emotional challenges related to infertility experienced by some. WHAT IS KNOWN ALREADY: Under transgender law in the Netherlands, sterilization was required for legal gender recognition until 2014, resulting in permanent infertility. The long-term consequences of this iatrogenic infertility in transgender adolescents who have now reached adulthood remain underexplored. STUDY DESIGN, SIZE, DURATION: Qualitative study design based on 21 in-depth one-on-one semi-structured interviews. PARTICIPANTS/MATERIALS, SETTING, METHODS: TGD people in a stage of life where family planning may be a current topic were eligible for participation. They all received gender-affirming treatment in adolescence prior to the legislation change in 2014. A purposeful sampling technique was used from participants of another ongoing study. Eleven people assigned female at birth and ten people assigned male at birth were included. Interview transcripts were thematically analysed using a modified version of Braun and Clarke's six steps theory. MAIN RESULTS AND THE ROLE OF CHANCE: Six main themes were generated: (i) personal considerations regarding fertility and fertility preservation in the past; (ii) external considerations regarding fertility and fertility preservation in the past; (iii) current vision on past considerations and decisions; (iv) Current experiences and coping with infertility; (v) future family building; (vi) advice regarding fertility and fertility preservation decision-making. LIMITATIONS, REASONS FOR CAUTION: Selection, recall, and choice supportive bias may play a role in interpreting our results. WIDER IMPLICATIONS OF THE FINDINGS: This study highlights the importance of tailored counselling and comprehensive information on fertility preservation for transgender individuals, especially adolescents, undergoing gender-affirming treatment. STUDY FUNDING/COMPETING INTEREST(S): N/A. TRIAL REGISTRATION NUMBER: N/A.

Permanently infertile couples and family building-a cross-sectional survey in Denmark.

STUDY QUESTION: Which decision-making factors influence family building among permanently infertile couples? SUMMARY ANSWER: Ethical, legal, and financial considerations outweigh genetic relatedness in decision-making, favouring domestic gestational surrogacy, if this were possible, over international options. WHAT IS KNOWN ALREADY: Permanent infertility affects 4-5% of people in the fertile age. Their family-building options include adoption, surrogacy, uterus transplantation, foster care, and intentional multiple parenthood. However, in most countries, including Denmark, legal barriers constrain these methods due to surrogacy restrictions, suspended international adoptions, and the experimental status of uterus transplantation. Despite existing research on surrogacy, adoption, and specific causes of permanent infertility, a significant gap remains in our understanding of how couples with permanent infertility make family-building decisions within these limited frameworks. STUDY DESIGN, SIZE, DURATION: This cross-sectional study with 150 permanently infertile Danish participants was conducted from June to November 2023 using an online questionnaire. Multiple strategies, such as online forums, fertility clinics, hospital departments, and snowballing, were used to recruit a diverse sample. PARTICIPANTS/MATERIALS, SETTING, METHODS: The study included couples aged 26-50 years facing permanent infertility due to the following primary causes: women without a uterus (15%), women with a non-functional uterus (47%) or women for whom pregnancy would be life-threatening (9%), male couples (16%), transgender partner couples (2%), and other causes (11%). The survey collected data on demographics, reproductive history, family-building choices, and communication strategies. Closed questions were analysed using descriptive statistics. MAIN RESULTS AND THE ROLE OF CHANCE: Among 150 respondents, 41% had used transnational surrogacy, 27% adoption, 14% chose to remain childless, and 19% were undecided. Critical factors on family-building decisions were ethical, legal, and financial concerns which ranked higher than genetic relatedness. Despite the complexity of family building, most participants were open about their child's origin and received social support. If all family-building methods were legal and available in Denmark, domestic gestational surrogacy would be the preferred method, with uterus transplantation and remaining childless being least popular. LIMITATIONS, REASONS FOR CAUTION: The sample size is relatively small, despite the use of a variety of recruitment strategies. Nevertheless, this has ensured a diverse cohort representing the different reasons for infertility and family-building choices. It is important to note that the strategies may have favoured individuals achieving parenthood. WIDER IMPLICATIONS OF THE FINDINGS: The finding of our study reveals a notable gap between available family-building options in Denmark and the preferences of couples facing permanent infertility. These insights could be instrumental for organizations reviewing and developing family-building frameworks. Furthermore, for healthcare professionals guiding couples experiencing infertility issues in their attempts to build a family, an understanding of these preferences is essential to facilitate informed decisions about their future family plans. STUDY FUNDING/COMPETING INTEREST(S): The project was financed by the Independent Research Fund Denmark. The authors have no conflict of interest to declare. TRIAL REGISTRATION NUMBER: N/A.

Intergenerational transmission of ADHD behaviors: genetic and environmental pathways.

BACKGROUND: We investigate if covariation between parental and child attention-deficit hyperactivity disorder (ADHD) behaviors can be explained by environmental and/or genetic transmission. METHODS: We employed a large children-of-twins-and-siblings sample (N = 22 276 parents and 11 566 8-year-old children) of the Norwegian Mother, Father and Child Cohort Study. This enabled us to disentangle intergenerational influences via parental genes and parental behaviors (i.e. genetic and environmental transmission, respectively). Fathers reported on their own symptoms and mothers on their own and their child's symptoms. RESULTS: Child ADHD behaviors correlated with their mother's (0.24) and father's (0.10) ADHD behaviors. These correlations were largely due to additive genetic transmission. Variation in children's ADHD behaviors was explained by genetic factors active in both generations (11%) and genetic factors specific to the children (46%), giving a total heritability of 57%. There were small effects of parental ADHD behaviors (2% environmental transmission) and gene-environment correlation (3%). The remaining variability in ADHD behaviors was due to individual-specific environmental factors. CONCLUSIONS: The intergenerational resemblance of ADHD behaviors is primarily due to genetic transmission, with little evidence for parental ADHD behaviors causing children's ADHD behaviors. This contradicts theories proposing environmental explanations of intergenerational transmission of ADHD, such as parenting theories or psychological life-history theory.

Exposure to parental depression in adolescence and proinflammatory phenotypes 20 years later.

Although the biological embedding model of adversity proposes that stressful experiences in childhood create a durable proinflammatory phenotype in immune cells, research to date has relied on study designs that limit our ability to make conclusions about whether the phenotype is long-lasting. The present study leverages an ongoing 20-year investigation of African American youth to test research questions about the extent to which stressors measured in childhood forecast a proinflammatory phenotype in adulthood, as indicated by exaggerated cytokine responses to bacterial stimuli, monocyte insensitivity to inhibitory signals from hydrocortisone, and low-grade inflammation. Parents reported on their depressive symptoms and unsupportive parenting tendencies across youths' adolescence. At age 31, youth participants (now adults) completed a fasting blood draw. Samples were incubated with lipopolysaccharide and doses of hydrocortisone to evaluate proinflammatory processes. Additionally, blood samples were tested for indicators of low-grade inflammation, including IL-6, IL-8, IL-10, and TNF-α, and soluble urokinase plasminogen activator receptor. Analyses revealed that parental depression across youths' adolescence prospectively predicted indicators of proinflammatory phenotypes at age 31. Follow-up analyses suggested that unsupportive parenting mediated these associations. These findings suggest that exposure to parental depression in adolescence leaves an imprint on inflammatory activity that can be observed 20 years later.

Parental Nurturance Moderates the Etiology of Youth Resilience.

Parenting behaviors are among the most robust predictors of youth resilience to adversity. Critically, however, very few studies examining these effects have been genetically-informed, and none have considered parenting as an etiologic moderator of resilience. What's more, despite the multidimensionality of resilience, extant etiologic literature has largely focused on a single domain. The current study sought to fill these respective gaps in the literature by examining whether and how parental nurturance shapes the etiology of academic, social, and psychological resilience, respectively. We employed a unique sample of twins (N = 426 pairs; ages 6-11) exposed to moderate-to-severe levels of environmental adversity (i.e., family poverty, neighborhood poverty, community violence) from the Twin Study of Behavioral and Emotional Development in Children. As expected, parental nurturance was positively correlated with all forms of resilience. Extended univariate genotype-by-environment interaction models revealed that parental nurturance significantly moderated genetic influences on all three domains of resilience (academic resilience A1= -0.53, psychological resilience A1= -1.22, social resilience A1= -0.63; all p < .05), such that as parental nurturance increased, genetic influences on youth resilience decreased. Put another way, children experiencing high levels of parental nurturance were more resilient to disadvantage, regardless of their genetic predisposition towards resilience. In the absence of nurturing parenting, however, genetic influences played an outsized role in the origins of resilience. Such findings indicate that parental nurturance may serve as a malleable protective factor that increases youth resilience regardless of genetic influences.

Alcohol Use Disorder Polygenic Risk Scores and Trajectories of Early Adolescent Externalizing Behaviors: Examining the Role of Parenting and Family Conflict in the Racially/Ethnically Diverse ABCD Sample.

This study examined the independent and interactive effects of alcohol use disorder genome-wide polygenic scores (AUD-PGS) and parenting and family conflict on early adolescent externalizing behaviors. Data were drawn from White (N = 6181, 46.9% female), Black/African American (N = 1784, 50.1% female), and Hispanic/Latinx (N = 2410, 48.0% female) youth from the adolescent brain cognitive development Study (ABCD). Parents reported on youth externalizing behaviors at baseline (T1, age 9/10), 1-year (T2, age 10/11) and 2-year (T3, age 11/12) assessments. Youth reported on parenting and family environment at T1 and provided saliva or blood samples for genotyping. Results from latent growth models indicated that in general externalizing behaviors decreased from T1 to T3. Across all groups, higher family conflict was associated with more externalizing behaviors at T1, and we did not find significant associations between parental monitoring and early adolescent externalizing behaviors. Parental acceptance was associated with lower externalizing behaviors among White and Hispanic youth, but not among Black youth. Results indicated no significant main effect of AUD-PGS nor interaction effect between AUD-PGS and family variables on early adolescent externalizing behaviors. Post hoc exploratory analysis uncovered an interaction between AUD-PGS and parental acceptance such that AUD-PGS was positively associated with externalizing rule-breaking behaviors among Hispanic youth, but only when parental acceptance was very low. Findings highlight the important role of family conflict and parental acceptance in externalizing behaviors among early adolescents, and emphasize the need to examine other developmental pathways underlying genetic risk for AUD across diverse populations.

CoDesign of a digital intervention for parents with bipolar disorder informed by integrated knowledge translation principles.

OBJECTIVES: To provide detailed information on the codesign of a digital intervention to support parents with bipolar disorder (BD) who have young children. Each step of this process is reported, as well as a detailed description of the final version of the intervention in line with the TIDieR framework. METHODS: Clinical experience and lived experience experts participated in online workshops, meetings, and remote feedback requests, informed by Integrated Knowledge Translation (IKT) principles. The IKT research group responded to each phase of recommendations from the knowledge users. RESULTS: Five clinical experience experts and six lived experience experts engaged with the codesign process. Their recommendations for principles, content, look, and feel, and functionality of the digital intervention were structured over five iterative phases. This led to a final implemented design that was identified by the clinical and lived experience experts (referred to together as the knowledge users group) as genuinely reflecting their input. CONCLUSIONS: The IKT principles offer an accessible structure for engaging with clinical and lived experience experts throughout a codesign process, in this case for a digital intervention for parents with BD. The resulting intervention is described in detail for transparency to aid further evaluation and development and to help other teams planning codesign approaches to intervention development.

Commentary: Optimism for the future of research on disruptive behaviors - an appreciation of good science as illustrated by Nobakht, Steinsbekk & Wichstrom (2023).

This paper by Nobakht, Steinsbekk & Wichstrom (2023) is a model of good science in the study of oppositional defiant disorder and conduct disorder. Their approach illustrates a thoughtful research design, statistical modeling sufficient to empirically evaluate developmental processes, and a full consideration of the theoretical implications of their work. This contrasts with a broad history of research on ODD and CD that far too often has only reified biased assumptions about these phenomena rather than rigorously scrutinizing them. Their demonstration of a unidirectional developmental flow of influence from ODD to interparental aggression, and thence to CD highlights a set of complicated developmental processes involving these disorders and their environment. It expands on evidence of the toll that ODD exerts on parents and provides guidance for more specific intervention. Standards in developmental psychopathology research should include testing bidirectional processes and employing designs that could falsify rather than reify existing beliefs. Examining key mechanisms in such processes will more rapidly generate improvements in assessment and treatment.

Toward a nuanced assessment of the role of intensive home visiting in improving outcomes for families: commentary on Catherine et al. (2023).

Families' experiences during the transition to parenthood and early childhood profoundly shape the lifetime trajectory of both parents and children, laying the foundation for societal inequities. Intensive home visiting programs, which aim to provide in-home support to socio-economically vulnerable parents during the transition to parenthood, are a prominent policy across the globe to provide support to less-resourced families. In this issue of the Journal of Clinical Psychology and Psychiatry, in their article titled 'Effectiveness of nurse-home visiting in improving child and maternal outcomes prenatally to age two years: A randomised controlled trial (British Columbia Healthy Connections Project)', Catherine et al. provide evidence from a randomized controlled trial of the impact of the Nurse-Family Partnership in Canada on child injury, language and behavior and birth spacing outcomes. This commentary discusses the paper's contribution and reflects on opportunities and challenges in building a nuanced understanding of the evidence-base supporting intensive home visiting programs.