Delta and spindle components in compressed spectral array during nocturnal sleep in infants with congenital cerebral malformation.

The correlation between the delta and spindle components in compressed spectral array in 18 infants with congenital cerebral malformation (from 4 months to 4 years of age) was studied throughout nocturnal sleep. In 7 (39%, Group A) out of 18 subjects, periodic changes of delta and spindle rhythm powers were noted in the sleep EEG. In 5 subjects (28%, Group B), delta but not spindle rhythm powers were found, and in the remaining 6 subjects (33%, Group C) neither delta nor spindle rhythm powers were found throughout nocturnal sleep. A significant decrease in the developmental quotient was found in group C as compared with group A.