EEG patterns of preterm infants, home environment, and later IQ.

As part of a prospective longitudinal study of preterm infants, sleep state organization and EEG patterns were studied at term date in 53 preterm infants as an index of the maturity and integrity of neurophysiological organization that might have implications for their later development. The rearing environments of the infants were also assessed, using time sampling of caregiver-infant interaction during home observations when the infants were 1, 8, and 24 months. The infants were tested at 4, 9, and 24 months on the Gesell Developmental Scale. At age 5 the children were tested by the Stanford-Binet Intelligence Scale, and at age 8 by the Wechsler Intelligence Scale for Children. In general, children who at term date showed less 407-Tracé Alternant EEG pattern in the entire record and particularly in quiet sleep had lower IQs beginning at 4 months and continuing to age 8. There was an exception, however, for those children being reared in consistently attentive, responsive environments. They, by 24 months and continuing to age 8, had higher IQ scores, equal to those of infants with more 407-Tracé Alternant, even if they had shown decreased amounts of 407-Tracé Alternant earlier.