Within-person changes in basal cortisol and caregiving modulate executive attention across infancy.

One pathway by which environments of socioeconomic risk are thought to affect cognitive development is through stress physiology. The biological systems underpinning stress and attention undergo a sensitive period of development during infancy. Psychobiological theory emphasizes a dynamic pattern of context-dependent development, however, research has yet to examine how basal cortisol and attention dynamically covary across infancy in ecologically valid contexts. Thus, to address these gaps, we leveraged longitudinal, multilevel analytic methods to disentangle between- from within-person associations of hypothalamic-pituitary-adrenal (HPA) axis activity and executive attention behaviors across infancy. We use data from a large longitudinal sample (N = 1,292) of infants in predominantly low-income, nonurban communities at 7-, 15-, and 24-months of age. Using multilevel models, we investigated longitudinal associations of infant attention and basal cortisol levels and examined caregiving behaviors as moderators of this relationship. Results indicated a negative between- and within-person association between attention and cortisol across infancy and a within-person moderation by caregiver responsiveness. In other words, on the within-person level, higher levels of cortisol were concomitantly associated with lower infant attention across the first 2 years of life. However, variation in the caregiver's level of responsiveness either buffered or sensitized the executive attention system to the negative effects of physiological stress.

Maternal anxiety symptoms associated with increased behavioral synchrony in the early postnatal period.

The presence of perinatal mood and anxiety disorders has typically been associated with decreases in the quality of mother-infant interactions. However, maternal anxiety symptoms during the postpartum period have been less studied than other mental health disorders like depression. In the current study, we examined associations among symptoms of maternal anxiety, maternal perceived stress, and mother-infant behavioral synchrony in the early postnatal period. Eighty-one mother-infant dyads participated in this study when the infants were 3 months old. Surveys were given to obtain demographic information and current maternal mental health symptoms, and dyads completed a 5-min free-play task to measure behavioral synchrony. Results indicated that maternal anxiety symptoms were positively associated with behavioral synchrony, but only for mothers reporting moderate levels of perceived stress. These findings highlight the differential impact of maternal postpartum mental health on behavioral synchrony and suggest that higher maternal anxiety symptoms during the postnatal period may play an adaptive role in fostering more dynamic mother-infant interactions.

Early Life Stress and the Development of the Infant Gut Microbiota: Implications for Mental Health and Neurocognitive Development.

PURPOSE OF REVIEW: We review the state of the literature examining associations between early life stress (ELS), gut microbiota, and neurocognitive development and mental health in animals and humans. We identify gaps in current models and areas for future research. RECENT FINDINGS: ELS is associated with changes in gut microbiota, which correspond to changes in affective and cognitive functioning in both animals and humans. Some of these ELS-induced psychological changes can be remedied by supplementation with probiotics in early life, suggesting a potential area for intervention for ELS-exposed children. Prenatal stress exposure is rarely studied in humans in relation to gut microbiota, but animal work has suggested important associations between prenatal stress and fetal programming that should be tested in humans. The gut microbiota plays an important role in the association between ELS, neurocognitive development, and mental health. More work is needed to fully understand these associations in humans.

A comparison of the infant gut microbiome before versus after the start of the covid-19 pandemic.

The COVID-19 pandemic and resulting public health directives led to many changes in families' social and material environments. Prior research suggests that these changes are likely to impact composition of the gut microbiome, particularly during early childhood when the gut microbiome is developing most rapidly. Importantly, disruption to the gut microbiome during this sensitive period can have potentially long-lasting impacts on health and development. In the current study, we compare gut microbiome composition among a socioeconomically and racially diverse group of 12-month old infants living in New York City who provided stool samples before the pandemic (N = 34) to a group who provided samples during the first 9-months of the pandemic (March-December 2020; N = 20). We found that infants sampled during the pandemic had lower alpha diversity of the microbiome, lower abundance of Pasteurellaceae and Haemophilus, and significantly different beta diversity based on unweighted Unifrac distance than infants sampled before the pandemic. Exploratory analyses suggest that gut microbiome changes due to the pandemic occurred relatively quickly after the start of the pandemic and were sustained. Our results provide evidence that pandemic-related environmental disruptions had an impact on community-level taxonomic diversity of the developing gut microbiome, as well as abundance of specific members of the gut bacterial community.

Neurophysiology of sustained attention in early infancy: Investigating longitudinal relations with recognition memory outcomes.

The ability to sustain attention is a critical cognitive domain that emerges in infancy and is predictive of a multitude of cognitive processes. Here, we used a heart rate (HR) defined measure of sustained attention to assess corresponding changes in frontal electroencephalography (EEG) power at 3 months of age. Second, we examined how the neural underpinnings of HR-defined sustained attention were associated with sustained attention engagement. Third, we evaluated if neural or behavioral sustained attention measures at 3-months predicted subsequent recognition memory scores at 9 months of age. Seventy-five infants were included at 3 months of age and provided usable attention and EEG data and 25 infants returned to the lab at 9 months and provided usable recognition memory data. The current study focuses on oscillatory power in the theta (4-6 Hz) frequency band during phases of HR-defined sustained attention and inattention phases. Results revealed that theta power was significantly higher during phases of sustained attention. Second, higher theta power during sustained attention was positively associated with proportion of time in sustained attention. Third, longitudinal analyses indicated a significant positive association between theta power during sustained attention on 9-month visual paired comparison scores such that higher theta power predicted higher visual paired comparison scores at 9-months. These results highlight the interrelation of the attention and arousal systems which have longitudinal implications for subsequent recognition memory processes.

Deprivation and threat as developmental mediators in the relation between early life socioeconomic status and executive functioning outcomes in early childhood.

There has been a shift in the study of childhood adversity towards a focus on dimensions of adversity as opposed to a focus on cumulative risk or specific adversities. The Dimensional Model of Adversity and Psychopathology (DMAP) proposes deprivation and threat as core dimensions of childhood adversity. Previous work using DMAP has found links between deprivation and cognitive development and threat and emotional development in adolescence, but few studies have applied this framework to a poverty context, in which children are at heightened risk for adversity experiences, and none have examined outcomes in early childhood. We use data from the Family Life Project (n = 1292) to examine deprivation and threat at child age 24 months as developmental mediators in the association between socioeconomic status (SES) measured at 15 months and executive functions (EF) measured at 48 months. In a multiple mediation model, lower SES was related to higher deprivation and threat. Deprivation was negatively associated with EF, and threat was not associated with EF. Deprivation fully mediated association between SES and EF. These results expand previous work using the DMAP and point to new directions in understanding children's cognitive adaptations to adversity.

Childhood Adversity and Dimensional Variations in Adult Sustained Attention.

BACKGROUND AND OBJECTIVE: Sustained attention is a transdiagnostic phenotype linked with most forms of psychopathology. We sought to understand factors that influence the development of sustained attention, by looking at the relationship between childhood adversity and adult sustained attention. PARTICIPANTS SETTING AND METHODS: Participants were 5,973 TestMyBrain.org visitors from English-speaking countries who completed a continuous performance task (gradCPT) of sustained attention and a childhood adversity questionnaire. We analyzed gradCPT performance using a signal detection approach. RESULTS: Discrimination ability (the main metric of performance on the gradCPT) was associated with total childhood adversity load, even when controlling for covariates related to age, gender, parental education, race, country of origin, and relative socioeconomic status (ß = -0.079, b = -0.032). CONCLUSION: Our results demonstrate that attention differences related to childhood adversity exposure can (1) be measured using brief, performance-based measures of sustained attention, (2) persist into adulthood, and (3) be detected at the population level. These results, paired with the well-documented associations between sustained attention and psychopathology, indicate that sustained attention may be an important mechanism for understanding early influences on mental health.