Parent cortisol and the neural underpinnings of attention and emotion regulation in infancy

• In Event: Adaptation, not deficit: Contextual and environmental influences of SES on neurodevelopment and self-regulation

Abstract

Introduction: Research suggests that parent stress is an important factor contributing to the development of child self-regulation abilities. In particular, infancy is a sensitive period for brain development during which the effects of parent stress may be especially pronounced. In particular, the caregiver’s level of (cumulative) stress, often measured physiologically by the hormone cortisol, may be an important factor contributing to the infant’s neurocognitive function and development. However, research has yet to examine the associations between chronic parental physiological stress and infant neural markers of developing self-regulation abilities. Thus, in the current study we investigated the effects of cumulative parent cortisol on infant neural activity longitudinally from 3- to 9-months of age.

Methods: Parents and their infants at 3-months of age were recruited from the New York City Metropolitan area to participate in this study. Families reflected a wide range of socioeconomic backgrounds (maternal ED=9-26 years, annual family income - $12k-$500K). Families were brought into the lab at 3-months of age and returned at 9-months. At the 3-month visit, a hair sample was collected from the parent and assayed for cortisol and infant EEG was recorded during an attention eliciting video paradigm (task adapted from Xie et al., 2017). Phases of sustained attention were indexed by coding infant looks and measuring heart rate deceleration. Frontal theta power (4-6 Hz; neural indicator of attention abilities) was calculated during phases of sustained attention. At the 3- and 9-month visit, five minutes of baseline EEG was recorded while the infant watched a passive stimuli video. Frontal alpha power (6-9 Hz) asymmetry was calculated by subtracting left frontal alpha power from right frontal alpha power (neural indicator of emotion regulation), such that higher values correspond to increased power in the right hemisphere.

Results: Between-person regression analyses indicated that higher levels of caregiver cortisol were associated with lower theta power during phases of sustained attention at 3-months and decreased alpha asymmetry at 9-months of age. Further, within-person analyses indicated a significant interaction between caregiver cortisol levels and change in infant alpha asymmetry from 3- to 9-months, such that higher cortisol levels were associated with a longitudinal decrease in alpha asymmetry across infancy.

Conclusion: Results suggest associations between chronic parent stress and the neural underpinnings of infant sustained attention at 3-months and emotion regulation at 9-months of age. Examining associations between caregiver stress physiology and infant neural activity may help elucidate early mechanisms connecting environments of risk to differences in infant cognitive and emotional development.

Authors

• Annie Brandes-Aitken, New York University
  Presenting Author

• Stephen Braren, New York University
  Non-Presenting Author

• Ashley Greaves, New York University
  Non-Presenting Author

• Karina Kozak, New York University
  Non-Presenting Author

• Natalie Hiromi Brito, New York University
  Non-Presenting Author