Examining a brain-environment interaction in predicting negative affectivity at 18 months
Year: 2026
Type: preprint
Abstract: Negative affect, a propensity to experience sadness, fear, distress, and anger, during infancy is robustly predictive of later anxiety and depression (Watson et al., 1988). Heightened negative emotions have also been associated with social skill difficulties in 4-year olds, suggesting that risk related to this temperament extends beyond internalizing symptoms (Smith & Hart, 2011). Longitudinal observation of negative affect suggests it is a stable trait that is likely to persist from infancy through middle childhood (Lovato et al., 2022), suggesting potentially enduring biological underpinnings. The aims of the present project are to 1) identify biological substrates shortly after birth that are correlated with negative affectivity, 2) examine correlations between the postnatal home environment and negative affectivity, and 3) investigate early life brain-environment interactions in predicting negative affectivity. Advancements in neuroscience have enabled identification of neural structures and networks implicated in negative affect and its subdomains (e.g., fear, anger, sadness) in adult populations. Cross sectional observational research conducted among healthy young adults has revealed heightened negative affect to be correlated with increased amygdala volumes and reduced thickness in subgenual and rostral anterior cingulate cortex regions (Holmes et al., 2012). Further, lesion studies highlight the amygdala and hippocampus likely play a causal role in human fear conditioning and maintenance of the fear response through associative learning (Bechara, A. et al., 1995; Debiec & Ledoux, 2004). With respect to neural networks associated with other emotional subdomains, the recall of anger-inducing memories activates a widespread network including regions in the prefrontal cortex, specifically the anterior cingulate cortex, medial temporal lobe, thalamus, hypothalamus, insula, brainstem, and cerebellum (Gilam & Hendler, 2015). Furthermore, asymmetrical activation in anterior regions may contribute to individual variability in fear and sadness (Fox & Davidson, 1988). Specifically, elevations in right-hemispheric regions are associated with higher negative affect, whereas left-hemispheric activity is inversely correlated with sad moods (Davidson & Henriques, 2000). Literature establishing links between adult brain regions and negative affect creates a theoretical foundation where we might expect to see early structural indicators associated with negative affectivity as early as infancy. However, the neonatal brain is characterized by more diffuse structural organization than adults, which may warrant exploring associations of brain regions outside those involved in adult negative affect. Few studies have linked variability in infant brain morphometry with negative affect in later infancy or early childhood. Amygdala volumes demonstrate consistent predictability of later negative affectivity. Two studies demonstrated smaller left amygdala volumes measured within an infant’s first three months predicted higher negative affectivity at 6 months (Demers et al., 2022; Di Paolo, 2025), whereas a third observed right amygdala volumes were positively correlated with negative affect scores during the first three years (Lasch, 2024). However, research with cortical structure volumes and negative affect do not yield as strong associations. One study found positive associations between concurrent prefrontal cortex gray (PFC) matter volume and negative affect at 9 months (Zhang et al., 2023). These associations do not remain in longitudinal models. Whole brain volumes observed at one month of age did not predict later infant negative affect scores repeatedly assessed at 3, 6, and 12 months (Schneider et al., 2023). This discrepancy may suggest that the rapid developmental transformations taking place in the PFC postnatally introduce variability in negative affect trajectories, thus rendering neonatal PFC volumes alone a poor predictor. However, because the early environment heavily shapes PFC organization, neonatal PFC volumes may only predict higher negative affectivity when combined with an adverse home environment. Parenting style is a key dimension of the early home environment that may enhance, or conversely buffer against, temperamental risk. Specifically, aspects of responsive parenting like greater use of supportive touch and vocalization are associated with lower negative affect in infants (McKay et al., 2019). Greater parental engagement in positive activities like reading or singing songs at 6 months also predicted lower negative affect at 9 months (Kotila et al., 2015). These studies underscore the importance of frequent, high-quality parent-child interaction. However, most studies to date have focused exclusively on the maternal-infant dyad, overlooking the important influence of additional caregivers. The present study will include parenting measures from both mothers and a secondary caregiver to help fill this important gap. In addition to parenting, objects and routines present in the household may be influential in temperament development (Putnam et al., 2024). For example, toy richness and maternal teaching qualities, including affection, responsiveness, encouragement and teaching, predict low intensity pleasure temperament, and tendency towards quiet and inhibited behavior (Rosenbaum & Orr, 2026). Although it is unknown whether cognitively stimulating home resources and routines are related to negative affectivity, they may be associated with alternate temperament domains like effortful control. Interestingly, effortful control has been shown to moderate the relationship between high negative affect and depression during times of stress (Gulley et al., 2016). To provide a more holistic understanding of neuroenvironmental predictors of infant temperament, the present project will include exploratory analyses that examine whether neural and environmental factors also associate with surgency and effortful control. Environmental experiences may influence developmental trajectories by contributing additional variability to associations between early neural structure and temperament. Such interactions may be particularly important in the context of early biological risk, as developmental outcomes among at-risk infants are notably heterogeneous. Research suggests that infants with heightened biological vulnerabilities, may experience more adaptive outcomes when reared in supporting environments, indicating that environmental factors can shape the expression of early risk. Gueron-Sela et al. (2015) demonstrated this phenomena among a cohort of preterm infants, with those exposed to high maternal stress and low triadic interaction, measured at 6 months, showing the lowest socioemotional outcomes at 12 months than preterm infants with low maternal stress or high-quality triadic interaction. The biological risk and environment interaction framework has been illustrated to also predict infant negative affect, such that preterm infants with more sensitive mothers at 6 months term-adjusted age showed more adjusted developmental outcomes compared to infants with more controlling mothers (Forcada-Guex et al., 2006). However, protective environmental influences are unlikely to operate uniformly across developmental domains, and individual aspects of the home environment may differentially buffer specific risks or promote distinct outcomes. Thus, examining multiple dimensions of the home environment may provide a more comprehensive understanding of the environmental factors that support resilience among infants with elevated biological risk at birth. This project has 3 aims: 1. Examine whether neonatal regional brain volumes prospectively associate with future negative affectivity at 18 months. 2. Examine concurrent associations between the home environment and negative affectivity. 3. Examine whether a favorable home environment weakens biological predisposition toward negative affectivity.
Institution: New York University
Language: English
Subfield: Clinical Psychology
Field: Psychology
Domain: Social Sciences
Open Access status: green
OpenAlex ID: W7166357087