Leveraging the science of early life predictability to inform policies promoting child health

Abstract

Addressing the tremendous burden of early-life adversity requires constructive dialogues between scientists and policy makers to improve population health. Whereas dialogues focused on several aspects of early-life adversity have been initiated, discussion of an underrecognized form of adversity that has been observed across multiple contexts and cultures is only now emerging. Here we provide evidence for “why unpredictability?”, including: 1. Evidence that exposures to unpredictability affect child neurodevelopment, with influences that persist into adulthood. 2. The existence of a translational non-human animal model of exposure to early life unpredictability that can be capitalized upon to causally probe neurobiological mechanisms. 3. Evidence that patterns of signals in the early environment promote brain maturation across species. 4. The uneven distribution of unpredictability across demographic populations that illuminates a possible focal point for enhancing health equity. We then outline the potential of unpredictability in terms of the “what”; that is, how might the concept of unpredictability be leveraged to inform policy? We emphasize the importance of interdisciplinary and community partnerships to the success of this work and describe our community-engaged research project. Finally, we highlight opportunities for the science of unpredictability to inform policies in areas such as screening, immigration, criminal justice, education, childcare, child welfare, employment, healthcare and housing.

1. Introduction

There exists sufficient evidence to support the importance of policies to address early life adversity and their promise to enhance lifetime health and development, and in particular to address mental health disparities (Shonkoff et al., 2021a, Shonkoff et al., 2021b). Ours and the work of others has identified unpredictability as a particularly potent form of early life adversity that has advanced theories of developmental origins of mental health and that can inform policies with the potential to improve the mental health of children and families. As the field embarks on translational and applied research and practice to address unpredictability, it is critical that the input of key stakeholders, such as parents and members of communities disproportionately exposed to unpredictable circumstances are considered and incorporated. Here we argue that there is good evidence for the “why” unpredictability as a catalyst for policy change. This strong rationale includes: 1. Evidence that unpredictability shapes neurodevelopment independently from other forms of early life adversity 2. That unpredictability offers a significant advantage by providing a robust translational model that enables probing causal mechanisms 3. That its relevance to cognitive and emotional development is observable across species and cultures 4. Because unpredictability in early life is unevenly distributed in the population, through addressing this form of early life adversity (ELA) there is strong potential to reduce mental health disparities. We then highlight that enhancing predictability represents an ideal policy target because it is an actionable form of adversity that offers opportunities for intervention at multiple levels.

1.1. What is unpredictability?

Unpredictability in the early environment is a unique early influence on development characterized by stochastic variation in events or exposures. It occurs in a broad range of contexts (e.g., parental, family, neighborhood) and in different distributions over time (e.g., from seconds to years). For example, food insecurity, neighborhood crime, frequent moves, parental separation, parental mood lability, and patterns of caregiver behavior all represent forms of unpredictability. The defining and common attribute of this early influence is that it cannot be anticipated or foreseen with a high degree of certainty.

Our model of unpredictability is grounded both in ecological theory and in foundational biological principles documenting that patterns of signals during sensitive periods of development play a fundamental role in determining maintenance of synaptic connectivity and neural circuit formation (Birnie and Baram, 2022, Davis and Glynn, 2024). The predictability of patterns of signals in early life plays a primary role in shaping development as is evident by observations of effects of unpredictability across cultures and diverse populations and in multiple species (Davis et al., 2017, Davis et al., 2022, Davis and Glynn, 2024, Molet et al., 2016). Leveraging experimental neuroscience models, we have shown that patterning of moment-to-moment signals sculpts neurocircuit maturation with implications for cognitive and emotional development. Research with moment-to-moment signals has a strong foundation in experimental neuroscience and can delineate mechanisms by which unpredictability influences development. Newly developed screening tools (see section IIIb) leverage recent mechanistic discoveries from these experimental models (Glynn et al., 2019, Lindert et al., 2022, Liu et al., in press).

1.2. Why unpredictability? Unpredictability in early life determines lifespan mental health trajectories

Predictability in the early life environment is of fundamental importance with long-lasting consequences for stress regulation, attachment, cognitive function, and emotion regulation (Ainsworth et al., 1978, Baram et al., 2012, Bowlby, 1951, Demers et al., 2022, Ellis et al., 2022, Feldman, 2007, Fiese et al., 2002, Glynn and Baram, 2019, Marsh et al., 2019, Sroufe, 2005, Xu et al., 2023). Importantly, unpredictability in early life exerts unique contributions to physical and mental health over the lifespan from other established forms of ELA such as poverty, abuse, and neglect (Davis et al., 2017, Davis and Glynn, 2024, Glynn et al., 2018, Glynn et al., 2019, Granger et al., 2021; Jirsaraie et al., 2024; Norona-Zhou et al., 2020; Spadoni et al., 2022). Of additional note, recent evidence indicates that although unpredictability is an independent predictor, it also represents one of the pathways by which other forms of ELA may affect development. For example, human research, supported by experimental models, indicates that exposure to poverty results in unpredictable parenting behaviors with implications for offspring development (Davis and Glynn, 2024). Experimentally induced limitations of bedding and nesting materials (impoverished bedding condition) lead to unpredictable behavior of the dam towards her pup (sensory signal entropy), which is causally implicated in neurodevelopment (Birnie and Baram, 2022). In human research, unpredictable parental signals (sensory and mood entropy) account for some of the association between environmental conditions such as poverty and child development (Davis and Glynn, 2024). That unpredictability represents a pathway by which other forms of ELA may impact child development (Davis et al., 2017, Davis and Glynn, 2024), further highlights unpredictability as a tractable target for prevention and intervention.

Acknowledging that the vast majority of research in psychology and neuroscience has focused on white, middle-class individuals from developed countries, it is critical to note that the role of unpredictability in child neurodevelopment is observable across cultures, geographic areas and socioeconomically diverse populations. We recently provided a survey of studies examining unpredictability and child mental health in populations that are race/ethnically, geographically and economically diverse (Davis and Glynn, 2024). Taken together these studies indicate that predictability is associated with cognitive and emotional development among families that are financially under-resourced or living in poverty as well as those from racially and ethnically minoritized backgrounds and that these salutary influences are observed beginning in infancy through adolescence (Davis and Glynn, 2024). There also is good evidence that unpredictability is associated with neurodevelopment across the globe including in South America, Africa, Asia, United Kingdom and Northern Europe. Finally, the influences of unpredictability are observed in geographically diverse settings -- similar associations are observed in both rural and urban contexts. These findings, coupled with the cross-species relevance of unpredictability (discussed below), provide support for the potential fundamental role of predictable signals in shaping child brain development and for the need for policies aimed at providing stability in children’s lives.

1.3. Why unpredictability? Translational model examining momentary unpredictability in parental signals

Unlike many forms of adversity, the existence of a robust translational non-human animal model of exposure to early life unpredictability can be capitalized upon to causally probe neurobiological mechanisms underlying effects of exposure to unpredictability at the momentary timescale, facilitating the development of targeted prevention and intervention efforts. Building on biological principles documenting the central role of patterned information for neural circuit development in sensory systems (Takesian et al., 2018, Wiesel and Hubel, 1963), our research includes assessment of unpredictability in the moment-to-moment timescale that is relevant for neuronal communication and thus, may be most critical for neural circuit formation during sensitive developmental periods (Birnie and Baram, 2022). To quantify the predictability of patterns of parental signals, we compute entropy rate. Entropy is associated with randomness across multiple scientific fields and to date we have successfully applied this approach both to parental sensory signals and parental mood (Davis et al., 2017, Davis et al., 2022, Davis and Glynn, 2024, Glynn et al., 2018, Glynn et al., 2019). Applying Shannon’s definition (Cover and Thomas, 2006), in the context of parental sensory signals, entropy rate of a sequence of parental signals provides a quantitative measure of the unpredictability of the next behavior in the sequence. This same approach can be applied across species (rats, mice, macaques, and humans) with the coding of species appropriate parental behaviors during a parent-child interaction (Davis et al., 2022, 2017). In all cases, entropy rate can then be computed with higher scores indicating greater unpredictability creating a measure of unpredictable parental signals (See https://contecenter.uci.edu/measuring-unpredictable-maternal-sensory-signals for coding manual and R code). Unpredictable parental signals can be evaluated both in the research laboratory and in ecologically valid contexts such as the home (Werchan et al., 2022). Evaluation of these signals can provide mechanistic insight into the role of unpredictability in sculpting brain development.

A robust set of findings now illustrate that high entropy, indicating unpredictable parental signals, predicts cognitive development throughout infancy and childhood (Davis and Glynn, 2024, Davis et al., 2022, 2017; Howland et al., 2021). Effortful control, an aspect of executive function that is involved in the purposeful overriding of a prepotent or dominant response (Miyake and Friedman, 2012) and strongly predicts both mental and physical health over the lifespan (Hankin et al., 2017, Joseph et al., 2021, Moffitt et al., 2011, Nigg, 2017), may be specifically vulnerable to exposure to early life unpredictability. Across multiple cohorts and continents our research demonstrates that unpredictable parental signals portend poor effortful control during infancy and childhood (Davis et al., 2019, Holmberg et al., 2022) including a reduced ability to inhibit prepotent responses (e.g., flanker task; Davis et al., 2019) and to wait for a tempting treat on delay of gratification tasks (Davis and Glynn, 2024) as well as parent report of self-regulation. Taken together this work, coupled similar findings observed by other investigators (Fields et al., 2021, Mittal et al., 2015, Nweze et al., 2021) indicates consistent links between exposures to more unpredictability and poorer effortful/inhibitory control one component of executive function; (EF; Miyake and Friedman, 2012). However, it is worth noting that emerging evidence also suggests that other EF components (cognitive flexibility and working memory) may be spared, or perhaps even enhanced, in response to exposures to unpredictability (Fields et al., 2021, Mittal et al., 2015, Nweze et al., 2021). The possibility that unpredictability affects EF in targeted ways is consistent with conceptual models emphasizing the role of ELA in shaping both risk and resilience in cognitive phenotypes (Belsky et al., 2012; Ellis and Del Giudice, 2019; Frankenhuis et al., 2016; Mushtaq et al., 2011; Young et al., 2022).

In addition to associations with effortful control, unpredictable parental signals associate with risk for psychopathology. High entropy predicts dysregulated physiological stress responses in infancy (Norona-Zhou et al., 2020) as well as elevated fear behaviors during infancy and early childhood and increased anxiety in middle childhood (Aran et al., 2024). Of note, patterns of parental emotional signals similarly play a critical role in shaping child emotional development. Characterized with mood entropy, unpredictability of parental mood increases vulnerability to internalizing problems such as anxiety and depression (Glynn et al., 2018; see https://contecenter.uci.edu/measuring-maternal-mood/ for R-code to compute mood entropy). The causal role of unpredictability is substantiated by experimental work showing that exposing pups to induced early life unpredictability (high entropy) leads to disruptions in memory and emotional functions in the juvenile and adult animal paralleling findings of longitudinal human research (Birnie and Baram, 2022, Birnie et al., 2022, Davis et al., 2022, 2017; Levis et al., 2022).

Cross-species evidence regarding the importance of unpredictable parental signals during sensitive periods of early life as a driver of neural circuit formation highlights unpredictability as a fundamental process shaping the developing brain. Neural responses to patterned sensory signals may be an evolutionarily conserved process that sculpts neural circuit formation across species. Using memory as an illustrative example, we see evidence that unpredictable patterns of parental momentary signals during infancy are linked to long term alterations in memory function and underlying neural circuits in rats, mice, macaques, and humans (Birnie and Baram, 2022, Davis et al., 2022, 2017; Granger et al., 2021; Jirsaraie et al., 2024). In experimental studies mechanisms are further explicated; exposure to unpredictable maternal sensory signals leads to attenuation of long-term potentiation (a hallmark of learning) and with impoverished dendrites and synapses in the dorsal hippocampus (Brunson et al., 2005, Oct 12, Ivy et al., 2010, Short and Baram, 2019), reflected in reduced dorsal hippocampus volumes (Molet, Maras, et al., 2016). The power of this translational model enables elucidation of the causal impact and neural mechanisms underlying human observational work with the synergistic implementation of experimental rodent studies. The consistency between experimental studies providing causal evidence for the neuroanatomical consequences of patterned parental sensory inputs and the observational human studies provides robust support for the role of unpredictability in early life in shaping neural circuit development.

The translational model described here examining the influence of exposures to unpredictability at a momentary time scale represents an important advance providing a critical building block that has been repeatedly identified as necessary to enable the development of policies to enhance child development – the identification of specific underlying neurobiological mechanisms (Ellis et al., 2022, Liu and Fisher, 2022). While the field has made progress in that domain, there remain significant gaps in our understanding of the suite of mechanisms underlying the influences of more distal components of unpredictability (e.g. housing instability or precarious parental work schedules; (Ellis et al., 2022). Although we anticipate that policies broadly increasing stability and predictability in the lives of families will have downstream organizing effects on momentary signals including the provision of predictable parental sensory inputs as well as parental mood stability, there is a need to identify and delineate co-occurring mechanisms.

1.4. Why unpredictability? The uneven distribution of unpredictability illuminates a possible focal point for reducing disparities and enhancing health equity

Individuals of historically and currently marginalized and systematically excluded backgrounds are at disproportionate risk of exposure to stress and adversity, often characterized by unpredictability (Allwood et al., 2021, Liu et al., 2020, Shonkoff et al., 2021a, Shonkoff et al., 2021b, Williams, 2018, APA Working Group Report on Stress and Health Disparities, 2017). For example, disparities in neighborhood conditions and the persistence of concentrated poverty due to long-standing residential segregation place marginalized communities at an elevated risk of intermittent and unpredictable community violence such as shootings, fights, and break-ins (Shonkoff et al., 2021a, Shonkoff et al., 2021b, Williams, 2018). These same communities often have unpredictable access to resources that promote healthy development— resources such as healthy food, clean and safe parks, uncontaminated drinking water, child care, education, healthcare, libraries, and community centers (Liu et al., 2018, Shonkoff et al., 2021a, Shonkoff et al., 2021b). In-depth research has demonstrated how structural racism contributes to cycles of economic hardship, unstable housing, eviction, and homelessness faced by marginalized families (Desmond, 2016). In fact, recent findings suggest that 50 % of people experiencing homelessness as members of families with children identify as Black (de Sousa et al., 2022). Racism and discrimination in the labor market is linked to greater unemployment within marginalized populations, often resulting in financial instability and other forms of unpredictability in the home (APA Working Group on Stress and Health Disparities, 2017). Much research has shown the disproportionate amount of disciplinary action, such as suspensions and expulsions, that Black and Latinx youth are subjected to in school, which is disruptive to everyday school routines and academic achievement over time (Liu et al., 2020, Shonkoff et al., 2021a, Shonkoff et al., 2021b). These early experiences of exclusionary punishment often push youth out of the education system, increasing their likelihood of involvement in the criminal justice system as adults (Bacher-Hicks et al., 2021). Indeed, Black and Latinx individuals, particularly males, are disproportionately likely to face discrimination by law enforcement and the criminal justice system, thus increasing unpredictability in their lives with intergenerational consequences (APA Working Group on Stress and Health Disparities, 2017; Shonkoff et al., 2020; Williams, 2018). Finally, a myriad of complex immigration policies that change with presidential administrations exacerbate unpredictability in the lives of immigrants to the United States. For example, zero-tolerance family separation policies in 2018 separated more than 2300 children from their parents across a five-week period, placing them in shelters and detention centers (Khullar and Chokshi, 2019). Also in 2018, proposed expansions to the “public charge” rule discouraged immigrants from enrolling in governmental assistance programs including healthcare assistance, housing assistance, and nutritional assistance, for fear it would disqualify them from applying for permanent residency (Khullar and Chokshi, 2019). As illustrated in Table 1, it is notable that all forms of adversity and unpredictability discussed here are interconnected and increase the likelihood of one another. For example, a recent study documented the association between food insecurity and preschool expulsion (Jackson and Testa, 2020). Further, as noted above, unpredictability across different timescales interact and it is likely that systemic factors, such as these impact parenting including the predictability of parental signals (e.g., sensory and mood) at moment-to-moment time scale. Addressing and increasing predictability in the lives of children and families necessitates addressing systemic drivers such as the ones discussed here— neighborhood conditions, housing, labor rights, criminal justice, school discipline, and immigration policies.

Table 1.

Examples of policy opportunities to address structural determinants of early life unpredictability and improve the health and well-being of children and their families.

Policy area	Policy targets	Facts to support action: evidence that unpredictability affects child development	Facts to support action: evidence that policy can promote predictability in the early environment	Facts to support action: evidence that policy affects child development
Advance Policies That Address Systemic Racism and Bias Advancing policies that address systemic racism and bias is a universal priority across all sectors described below given that racism and discrimination contribute in myriad ways to inequitable access to services and environments that promote predictability.
Enhance Access to Resources	Increase provision of and access to refundable tax credits (Michelmore and Pilkauskas, 2022) Increase enrollments in social safety net programs (e.g. Lengthen and align eligibility periods; (Rosenbaum, 2015) Establish structures to prevent lapses and churn in program enrollment. (Maximize the use of administrative renewals based on trusted data sources that reduce families’ paperwork requirements; Wagner and Huguelet, 2016)	Childhood poverty increases risk of child exposures to many forms of unpredictability and is associated with compromised neurodevelopment and mental health (Davis and Glynn, 2024, Lund et al., 2011) Income volatility in childhood, independent from level, predicts increased likelihood of a mental health diagnosis as well as decreased educational attainment in adulthood (Cheng et al., 2020; Hardy, 2014)	The Earned Income Tax Credit (EITC) provides critical wage subsidies to offset inconsistency in income faced by parents with unstable or precarious work schedules (Michelmore and Pilkauskas, 2022) Tax credits enhance housing stability, food security and parental mental health (Gangopadhyaya et al., 2020, Lenhart, 2023, Pilkauskas et al., 2018) Many states have successfully implemented policies linking SNAP and Medicaid renewals to reduce enrollment gaps (Wagner and Huguelet, 2016)	Programs such as the EITC, are associated with improved birth outcomes and these improvements are greater when the benefits are more generous (Markowitz et al., 2017) EITC is associated with fewer child behavior problems (Hamad and Rehkopf, 2016) better child test scores and increased probability of college attendance (Chetty, Friedman, et al., 2011)
Early Screening	Implement systems for screening in schools and pediatric clinics	Early screening for unpredictability in the financial, housing, school, and health domains is critical to reduce the impacts of ACEs (Chung et al., 2016) Brief screening tools for unpredictability can identify families in need of support (Lindert et al., 2022)	Screening for early life adversity increases service referrals and increases the probability that children receive behavioral health services (Loveday et al., 2022)
Healthcare	Enhance anticipatory guidance for children and families to promote routines and predictability Expand access to affordable healthcare Increase support for parental mental health care Improve equity in healthcare	Access to health care and integrated mental health and parenting support promotes child wellbeing and positive predictable parenting (Bogin, 2006, Piotrowski et al., 2009) Unpredictable parental mental health is linked to increased child psychopathology and poorer cognitive development (Bailey et al., 2021, Glynn et al., 2018, Howland et al., 2021, Rinne et al., 2022, Sandman et al., 2012)	The Affordable Care Act led to over 20 million people gaining health insurance and the uninsured rate among children fell to the lowest on record in 2016 (Burak et al., 2019; Fry-Bowers, 2021). The Affordable Care Act covers preventive services for children that are critical for maintaining child health (Fry-Bowers, 2021) Decreasing support for Affordable Care Act related policies after 2016 resulted in the rate of uninsured children to increase from 4.7 % to 5.2 % (Burak et al., 2019) Family centered, culturally responsive, and place based, health and developmental services integrated into pediatric care and in communities can facilitate connection of families to needed support services (Bogin, 2006, Willis and Robinson, 2020).	Policies supporting stable, evidence based, community partnered home visitation programs to support maternal-child health can improve birth outcomes and maternal and child health (Thompson et al., 2011)
Employment	Optimize family and sick leave, fair work week legislation and minimum wage policies	Unpredictable income predicts child cognitive and school performance (Gennetian et al., 2015, Sosu and Schmidt, 2022) Inconsistent parental employment (e.g. shorter tenure, job churning) is associated with child externalizing problems (Pilkauskas et al., 2018) Precarious parental work schedules predict child internalizing and externalizing behavior problems (Schneider and Harknett, 2022)	Increasing minimum wage promotes family stability by reducing in payday loan usage, delinquency, divorce rates and exposures to stressful life events among pregnant women (Bethmann and Cho, 2022, Dettling and Hsu, 2021, Karney et al., 2022) Fair workweek legislation organizes parental work schedules, enhances parental sleep quality and mental health, decreases childcare and income instability (Harknett et al., 2021)	Paid family leave is associated with increased rates of breastfeeding and healthier children (Huang and Yang, 2015, Lichtman-Sadot and Bell, 2017)
Food	Enhance funding for nutrition programs (e.g. SNAP, WIC, school lunch programs) Fund vouchers and incentive programs to subsidize costs of healthier foods Enhance access to food pantries and farmers’ markets	Food insecurity predicts poorer youth mental health including increased risk of anxiety, depression, and substance use (McLaughlin et al., 2012) Fluctuations in access to food predicts poor child math and reading exam performance (Gassman-Pines and Bellows, 2018)	SNAP and WIC are highly effective at reducing food insecurity (Seligman and Berkowitz, 2019) SNAP reduces psychological distress among recipients (Oddo and Mabli, 2015).	School meal programs are associated with increased attendance, better cognitive performance and fewer behavior problems (Bethmann and Cho, 2022, Wall et al., 2022) WIC improves child cognitive development (Guan et al., 2021;Caulfield et al., 2022),
Housing	Support eviction protection programs Increase housing affordability Enhance long-term housing support programs	Unstable housing is associated with poorer caregiver mental health, compromised child health and increased likelihood of developmental delays (Sandel et al., 2018a, Sandel et al., 2018b) Housing affordability predicts child cognitive achievement (Newman and Holupka, 2016) Evictions predict increased risk of adverse birth outcomes and poorer neurodevelopment in children (Ramphal et al., 2023)	Provision of long-term housing assistance promotes stable housing, improves parental mental health, decreases incidence of domestic violence and reduces number of schools attended (Gubits et al., 2016)	Provision of long-term housing assistance decreases child behavior problems (Gubits et al., 2016)
Education	Require restorative justice practices in schools Implement teacher service scholarship and loan forgiveness programs and teacher induction and mentoring programs to reduce teacher burnout and turnover	School suspensions and expulsions create instability in lives of children and families and are associated with increased negative behavior, worse academic performances, and later criminal victimization, criminal involvement, and incarceration (Wolf and Kupchik, 2017) High rates of teacher turnover, especially among early career teachers and in urban districts and schools serving historically marginalized students, create unpredictability in students’ lives and are correlated with decreased student achievement (Carver-Thomas and Darling-Hammond, 2019, Ronfeldt and McQueen, 2017)	Restorative justice reduces suspensions and disparities in rates by race and income and promotes school safety and connectedness (Augustine et al., 2018, Todic et al., 2020) Service scholarship and loan forgiveness programs are effect incentives for recruiting and retaining individuals in teaching (Carver-Thomas and Darling-Hammond, 2019) Teacher induction and mentorship predicts less teacher migration and attrition (Ronfeldt and McQueen, 2017)	Restorative justice predicts fewer physical health problems and higher GPA (Augustine et al., 2018, Todic et al., 2020)
Childcare	Support affordable childcare such as Head Start Establish universal preschool Provide after school care	Predictable childcare including stable caregivers and consistent childcare arrangements and settings reduces behavioral problems and improves socioemotional development (e.g., NICHD Early Child Care Research Network 1999, Claessens and Chen, 2013; Morrissey, 2009; Pilarz and Hill, 2014)	Affordable childcare and programs such as Head Start can increase predictability of care in childcare and provide support and encouragement of predictability in the home environment to families. (US Department of Health and Human Services, 2023) Successful implementation of citywide aftercare programs involves collaboration with community partners and stakeholders including city government, schools, community members and foundations (Holleman et al., 2010, Spielberger et al., 2016)	Evidence suggests that after school programs can reduce child problem behaviors and improve school performance and prosocial behaviors when they are consistently available, with stable consistent staffing and include quality programing, foster positive relationships with peers and adults (Cross et al., 2010, Spielberger et al., 2016, Zief et al., 2006)
Child Welfare	Optimize foster care placement stability Reduce barriers to kinship care and prioritize placement with siblings Enhance systems connecting families with services (e.g., financial, logistical, social support, legal support, and mental health support) Incentivize stability in caseworkers, therapists, lawyers	Fewer foster care placements improves cognitive performance, school performance and reduces externalizing problems (Clemens et al., 2018, Geller et al., 2012, Geller et al., 2009) Factors that support foster care placement stability include access to support systems and economic resources, kinship/family placements, placements with siblings, parenting support including increasing routines (Font and Kim, 2022, Vanderwill et al., 2021; Vanderwill et al., 2021) Kinship care leads to longer foster care placement in the same home and fewer placements therefore decreasing unpredictability (Vanderwill, 2021) and kinship care protects against development of mental health problems (Dubois-Comtois et al., 2021)	Policies aimed at reducing barriers to kinship care include licensing that prioritizes placement with family members including waiving non-safety related standards, providing financial support, and reducing logistical barriers such as transportation to schools (Children’s Bureau, 2023) The Families First Prevention Services Act passed in 2018 implemented services to support children staying safely with their families. The Indian Child Welfare Act (ICWA) promotes the rights of American Indian/Alaska Native children to be connected to their tribe and their extended family, elders, community, and culture (Children’s Bureau, 2023) tandards for Relative or Kinship Foster Family Homes," 2023) Policies and intervention programs can increase financial assistance, legal support, social support services and mental health treatment for foster families, especially kinship caregivers who are less likely to receive services (Lin et al., 2014)	Policies that support kinship care, increase connections to support services and provide community-based support and mental health treatment promote placement stability and improve child mental health, self-esteem and school performance (Konijn et al., 2019, Lin, 2014)
Immigration	Support state sanctuary and inclusionary policies Expand eligibility for state and federal assistance among undocumented individuals Give precedence to policies that reduce family separation due to immigration	Changing immigration policies in the U.S. create unpredictability in the lives of immigrants in terms of what rights and resources they have access to (for example, employment, voting, driver’s license, food assistance, healthcare, etc.), in turn impacting physical and mental wellbeing (Hodges et al., 2024, Khullar and Chokshi, 2019, Koball and Hartig, 2020, Martinez et al., 2015) Forced parent-child separations due to a parent being arrested, detained, or deported results in heightened instability and unpredictability in children’s lives, including potentially being placed in foster care (Dreby, 2012)	DACA has lowered rates of poverty among recipients, thus increasing household stability and predictability (Valdez et al., 2022) DACA increases stability through education and employment opportunities, earnings, and health care coverage for recipients (Gonzales and Bautista-Chavez, 2014) Sanctuary policies for undocumented immigrants improves likelihood that children in immigrant households have a consistent healthcare provider, an important source of predictability (Koball and Hartig, 2020)	Mothers’ DACA eligibility was causally linked to decreased adjustment and anxiety disorder diagnoses among their children (Hainmueller et al., 2017) Many state-level inclusionary policies (e.g., extension of public services and benefits to undocumented immigrants) are associated with improved psychosocial outcomes among Latinx adolescents (Hodges et al., 2024)
Criminal Justice	Prioritize policies to reduce family separation due to incarceration Advance policies to reduce discrimination in arrest and conviction Support reentry programs (job training, education, housing)	Parental incarceration increases unpredictability in multiple domains including financial instability, food insecurity, separation from parents, attachment disruption, entry into the foster care system, housing instability (Dallaire, 2007; Kids Count, 2016; Turney and Goodsell, 2018) Parental incarceration increases child behavioral problems and child incarceration (Geller et al., 2012, Geller et al., 2009)	Policies can require consistent visitation and mental health support for children of incarcerated parents (Kids Count, 2016). Further, parenting training programs can increase feelings of parental competence and empathy for their children (Turney and Goodsell, 2018). Policies that provide incarcerated parents with specific training for high quality jobs and job placement assistance can increase their ability to provide for their families upon release and decrease recidivism (Kids Count, 2016) Changing state and federal policies can assist returning parents to find stable houses by preventing landlords and employers from discriminating against individuals based on arrest records can increase stable housing (Kids Count, 2016)	Programs allowing for consistent visitation are important for the parent-child attachment relationship (Kids Count, 2016; Weller and Shaver, 2010) Programs that increase family income for children with incarcerated parents show benefits on child educational attainment and reduced criminal behaviors (Turney and Goodsell, 2018)

2. Advancing both the why and what: the crucial role of community engagement

Science plays a critical role in informing policy and practice. Therefore, scientists have an ethical duty to conduct and disseminate research in a thoughtful manner that strives to improve equity and well-being for all, partly through “privileg[ing] and honor[ing] the communities’ priorities in order to foster and repair the trust that has historically been betrayed” (APA Task Force on Race and Ethncity Guidelines in Psychology, 2019, p.31). In our research on unpredictability funded by the State of California’s Precision Medicine Initiative, we have sought to do this through two complementary approaches to soliciting community feedback and guidance. First, we held a series of Community Engagement Studios (CES) in partnership with University of California Irvine’s Institute for Clinical and Translational Science. CES is a structured program that improves the design, implementation, and dissemination of research studies by assisting researchers in gathering project-specific input from relevant community stakeholders in the early stages of its development (Joosten et al., 2015). A key component of our study was implementing screening for unpredictability in pediatric clinics; therefore, we held four studios to hear from parents (English and Spanish language-preferring) as well as pediatricians and allied health professionals. All studios were held via video conference and lasted approximately 1.5 h. Participants first listened to a brief presentation from our study team about our research goals and then shared their reactions, suggestions, concerns, and remaining questions related to the project. Participants were compensated for their time and their feedback informed many aspects of our ongoing research project (Liu, in preparation). For example, parents provided the insight that answering screening questions regarding unpredictability in their homes would encourage reflection on the influences of their own parenting practices and primary care providers commented on how the screeners provided important information and might stimulate conversations about additional important parenting behaviors or child experiences.

Secondly, we assembled a racially/ethnically, vocationally, and socioeconomically diverse Community Advisory Board (CAB) for our study. Selected CAB members include community leaders, advocates, parents, field experts, representatives of nonprofit organizations, clinicians, and medical students. Compensation is provided to non-academic CAB members for their time, and small tokens of appreciation (i.e., gift cards) are provided to academic CAB members. Quarterly CAB meetings are held virtually, and the study team hosts an annual in-person event. Since its inception, CAB member input has influenced our study recruitment processes, variables explored, methods for study implementation, and plans for analysis. As summarized in Fig. 1, the CAB members made substantial contributions and enhancements to our research methods by deepening our thinking about ACEs, through suggestions for broaden research methods and by suggestions to improve the research experience for our participants. For example, CAB members encouraged more consideration of the interaction of structural variables with unpredictability, prompting our plan to incorporate neighborhood-level data into our analyses. CAB discussions also spurred deeper consideration of the unique demographics and cultural norms of our study families, leading to revisions and additions to our study design such as translating the QUIC into additional languages and adding measures to better capture multigenerational household structures. Our CAB also provided fruitful connections to community organizations and events that assisted with study outreach and recruitment. On a questionnaire distributed to CAB members to explore the perceived value of CAB participation, 100 % agreed that participation in the CAB was worthwhile, 100 % agreed that their perspectives were valued during CAB meetings, and 88 % shared that they would recommend the CAB to others. Positive feedback themes that arose on review of free-response feedback highlighted enjoyment in providing feedback to the team, value for sharing feedback in relation to one's own experiences, and an appreciation for being heard and learning through the different perspectives of fellow CAB members. As our research study progresses, the CAB will continue to be involved through opportunities for co-authorship and providing feedback on analyses, interpretation, and dissemination of results. CES and CAB are both feasible and vital tools that can be used to optimize research questions, design, implementation, and analysis, and to affirm and empower community members. Partnering with diverse stakeholders has the potential to enhance representation of systematically excluded and marginalized communities in research and support innovation.

Fig. 1.

Summary of Community Advisory Board contributions.

3. The what: informing policy to enhance mental health

As awareness grows regarding the significance of unpredictability in the early environment as a robust determinant of child neurodevelopment, the impetus to create and enhance evidence-based policies and interventions that address this aspect of the early environment become more urgent. As discussed above, to improve child mental health and reduce health disparities, multilevel intervention is necessary that focuses not only on the individual, but that also address the social and physical environments in which that individual resides (Shonkoff et al., 2021a, Shonkoff et al., 2021b). One promising aspect of unpredictability is that there exist actionable intervention opportunities to address at multiple levels. At the individual level potential targets for policy intervention would include parent education that would result in provision of more predictable parental care and structure in the home environment (Bick et al., 2019, Dozier et al., 2018, Hwang et al., 2013, Luby et al., 2020) as well as parental mental health services which could address emotional instability (Byrd et al., 2021, Hankin et al., 2023). Table 1 presents opportunities to address structural drivers of unpredictability in children’s lives and contains evidence that these opportunities exist across many domains including education, healthcare, employment, immigration, child welfare, and criminal justice. We also provide here associated evidence suggesting that the implementation of these policies promotes predictability and in some cases in which there has been direct evaluation of their efficacy in improving child health, that these policy-induced increases in predictability have benefits for child well being. We highlight here that these broad policies which promote stability in the lives of families, will likely affect child development through multiple channels. For example, stable healthcare will directly increase access to critical services ranging from consistent immunizations to mental health support. Stable healthcare likely also has downstream benefits through decreasing parental stress and supporting parental mental health both of which are likely to increase parental behavioral and mood predictability. Examination of Table 1 also identifies gaps in our evidence base to support investment in these policies highlighting two themes: 1. A dearth of studies that examine policy implementation, changes in unpredictability, and child outcomes together 2. Studies that identify the precise mechanistic pathways through which alterations to unpredictability might exert salutary influences on child health and well-being.

Below we discuss two concrete examples in more detail of how unpredictability might be successfully addressed through policies aimed at eliminating precarious work schedules and introduction of screening for unpredictability in pediatric primary care settings.

3.1. The what: fair workweek policies stabilize the lives of children and their families

Low-income workers, particularly those employed in the retail and food service sectors, are widely subjected to unpredictable or “precarious” work characterized by schedules that vary from day to day or week to week, on-call work, frequent last-minute changes to shift timing and short advance notice of weekly schedules. Recent estimates indicate that those working in the retail and food service sectors alone represent 17 percent of the US workforce and that these workers represent 1 in 10 parents of American children (Luhr et al., 2022). Not only does precarious work represent a source of unpredictability in children’s environment, but it results in increasing child exposure to other forms of unpredictability, including interfering with parents’ ability to provide consistent childcare and increasing family income volatility (Finnigan, 2018, Luhr et al., 2022, Schneider and Harknett, 2022). A growing number of studies document that this form of unpredictability impacts child development – it predicts increased internalizing and externalizing problems in both childhood and adolescence (Johnson et al., 2012, Schneider and Harknett, 2022). Recent policy innovations dubbed Fair Workweek laws legislating predictable work schedules have been adopted in several cities and states and show great promise as a policy intervention point to address unpredictability (Ananat and Gassman-Pines, 2021). Data suggest that these laws do in fact organize work schedules as intended (Harknett et al., 2021) and this organization has several positive downstream effects including increasing parental sleep quality and mental health, decreasing childcare and income instability, and improvements in child emotional outcomes (Harknett et al., 2021). In addition to these benefits for workers and their families, studies of schedule stability interventions document improvements in both worker productivity and sales (Kesavan et al., 2022), providing additional motivation for widespread implementation.

3.2. The what: feasibility of screening for unpredictability in pediatric primary care

Inspired by the growing awareness of developmental origins of physical and mental health, leading health policy and professional organizations are increasingly advocating screening for adversity in early life (Centers for Disease Control and Prevention, 2019, Garner and Shonkoff, 2012) We have recently begun efforts to expand this screening beyond previously recognized sources of toxic stress and adversity (Felitti et al., 1998) to include unpredictability. As a first step towards this goal, we developed and validated a short version our 38-item assessment the Questionnaire of Unpredictability in Childhood (Glynn et al., 2019), which assesses unpredictability in the social, emotional and physical environments (Liu et al. in press). The QUIC-5 is valid for use in Spanish and English and has both a caregiver version that is used to assess unpredictability in the home environment of children ages 0–18 and self-report version that is validated for use at age 11 and above (Lindert et al., 2022). Both the theoretical foundation and the validation of the QUIC draw on our understanding of the role of moment-to-moment signals in sculpting brain maturation. Our prospective longitudinal investigations demonstrate that the QUIC is related to unpredictability at multiple timescales including both parental sensory and mood signals (Glynn et al., 2019). Both the full-length QUIC and the QUIC-5 predict mental health profiles including executive function, reward and threat learning, depression, anxiety and anhedonia across genders and in children, adolescents and adults (Davis and Glynn, 2024, Gillespie and Rao, 2022, Glynn et al., 2019, Lindert et al., 2022, Liu et al., in press, Spadoni et al., 2022, Xu et al., 2023). As a next step in our translational work, funded by the State of California’s Precision Medicine Program, we have implemented screening at annual well-child visits in 19 clinics affiliated with the Children’s Hospital of Orange County. As discussed above, this work has been guided by our community engagement activities, which provide crucial insights into our approach and have facilitated our success with implementation. The QUIC-5 screen has been easily incorporated into clinic workflows with strong support from primary care providers and allied health professionals in these pediatric primary care settings. To date, we have screened more than forty-thousand children, and the next step will be to link exposures to unpredictability to child mental and physical health outcomes. We also will compare the predictive utility of the QUIC-5 (Lindert et al., 2022) to ACEs screening (Koita et al., 2018) occurring in tandem at these clinic visits, to confirm that the QUIC provides additional predictive power. It is our hope that this large-scale demonstration project will provide the foundation and justification for interventions targeting unpredictability in the household in pediatric primary care, as well as more widespread screening for this novel ACE.

4. Conclusion

Along with the opportunities for addressing this form of early life adversity at multiple levels, unpredictability possesses two additional characteristics that support its potential utility as a target for prevention and intervention. First, although we do conceptualize exposure to unpredictability as a form of early life adversity, predictability also is a promotive factor and increasing predictability in the early of environment has the potential to exert positive developmental influences either directly or indirectly by buffering the effects of other forms of ELA (Davis and Glynn, 2024). There is a growing literature that elucidates the salutary influences of predictability on child cognitive and emotional development. It also is likely that creation of structure and predictability in youths’ environments may additionally buffer or protect them from other adversities present in their lives such as poverty, parental substance use, and divorce (Betancourt et al., 2013, Crespo et al., 2013, Guidubaldi et al., 1986, Wolin and Bennett, 1984) and also from community or societal-level stressors such as natural disasters or global pandemics (Bates et al., 2021, Gadermann et al., 2021, Glynn et al., 2021, Rosen et al., 2021). Second, to further leverage a strengths-based perspective, aspects of interventions to address unpredictability are amenable to culturally-responsive and tailored approaches that can capitalize on the existing strengths and needs of an individual family. For example, while routines are crucial for scaffolding child development, an intervention approach could include providing families with a menu of options for creating that consistency – while a bedtime routine might not be feasible in all families, perhaps a consistent breakfast time together most days might be. Similarly, there is good evidence to support the positive developmental effects of family rituals and traditions (Fiese et al., 2002), and the choice of which rituals to prioritize could be determined by an individual family’s values and cultural context – it is simply the consistency with which those traditions are practiced that represent the key target of the prevention or intervention.

There now exists a body of knowledge regarding the role of predictability in early life and its fundamental importance for neurodevelopment that urgently calls for implementation of policies that address this aspect of the early environment and in doing so improve mental health across the lifespan. Not only is unpredictability associated with altered cognitive and emotional phenotypes that are observable across the developmental continuum from infancy through adulthood as well as across cultures and species, but the existence of a translational model allows probing causal mechanisms and delineation of underlying neurobiology. Fortunately, many feasible opportunities for policies to address this form of early life adversity exist and therefore enhancement of predictability achieved through meaningful partnerships with community stakeholders has the potential to improve the lives of both children and their families, reduce mental health disparities and promote health equity.

CRediT authorship contribution statement

Elysia Poggi Davis: Writing – review & editing, Writing – original draft, Software, Funding acquisition, Conceptualization. Candice Taylor Lucas: Writing – review & editing, Writing – original draft, Supervision, Project administration, Methodology, Investigation, Formal analysis, Conceptualization. Sabrina R. Liu: Writing – review & editing, Writing – original draft, Supervision, Project administration, Methodology, Investigation, Formal analysis, Conceptualization. Laura M. Glynn: Writing – review & editing, Writing – original draft, Supervision, Software, Project administration, Methodology, Investigation, Funding acquisition, Data curation, Conceptualization.

Declaration of Competing Interest

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Data availability

we provided links to relevant code.