Improving Brain Development in Medically Healthy Premature Infants

From 28 to 33 weeks' gestation, significant neurological reorganization takes place, initiating fetal behavioral individuality and capacity for extrauterine survival. Infants born at this transitional stage exhibit unexpectedly significant brain dysfunction as they develop and age. The majority of these infants will develop psychomotor, cognitive, and attentional function deficits as well as emotional vulnerability and substandard school performance. Research suggests that these symptoms are due to a central deficit in frontal lobe processing of complex information. This central deficit may result from increased vulnerability of cerebral white matter during the last trimester of gestation, its phase of most rapid development. Persistent stress due to inappropriate sensory stimulation may contribute to alteration of early brain structure and function. This study will identify specific adaptations of the preterm brain to the transient NICU experience in order to estimate the potential of such experience in remodeling neuroanatomical structure and neurodevelopmental function. Further, the study will evaluate a program of specialized developmental care within the NICU environment.

The study's specialized developmental care model views the preterm infant as a fetus and attempts to reduce the discrepancy between the technological hospital environment and the mother's womb. A developmental specialist team will support the NICU caregivers. The developmental specialists will observe the infant's behavior and use these observations to formulate descriptive neurobehavioral reports and suggestions, to structure caregiving procedures in coordination with the infant's sleep/wake cycle, and to maintain the infant's well-regulated behavioral balance. The goal of the intervention is to promote the infant's strengths while reducing the infant's self-regulatory vulnerability.

Sixty medically healthy infants born between 28 and 33 weeks' gestation will be randomly assigned to standard NICU care or specialized developmental care. Preterm infants will be compared to 30 healthy full term infants. All infants will be assessed at 42 weeks' postconceptional age in three neurodevelopmental domains: neurobehavioral function, neuroelectrophysiological function, and neuroanatomic structure. Assessments will focus on distinct regions of the brain (occipital and frontal lobes) and the corpus callosum (which connects the right and left sides of the brain).

Inclusion criteria

for Preterm Infants

• Born at Brigham and Women's Hospital (BWH), Boston
• Family residence in the greater Boston area
• Gestational age at birth of 28 to 33 weeks assessed by mother's dates, the Ballard assessment, and prenatal ultrasound as available
• Birthweight, height, and head circumference appropriate (10th to 90th percentile) for gestational age
• 1 and 5 minute Apgar >= 7
• Endotracheal intubation and mechanical ventilator support, including continuous positive airway pressure (CPAP), for < 48 hours after delivery
• Normal cranial ultrasound(s) within first 7 days of life
• Mother between 15 and 39 years old
• Telephone access
• Sufficient English language facility to assure successful communication and follow-up

Exclusion criteria

for Preterm Infants

• Use of dopamine or hydrocortisone
• Chromosomal or congenital abnormalities (e.g., Down's, Turner's, Klinefelter's syndromes)
• Congenital or acquired infections (e.g., TORCH, HIV, sepsis)
• Major maternal illness; diagnosed mental and/or emotional impairment; reported alcohol, nicotine, or illegal drug use and/or positive urine toxicity screen; or chronic medication treatment (e.g., synthroid, insulin, steroids)