Changes in respiratory patterns were studied in prematures from 30 wks. conceptional age to 8 mons. past term and in full term infants between 40 wks. conceptional age and 8 mons. past term. Regular respiration was found to increase greatly after 36 wks. conceptional age, while very little periodic breathing or apnea were seen after this age. Irregular respiration accounted for 50% of each 2—3 hr. record, until 8 months past term, when it was less. In addition, the maturational increase in regular respiration was concurrent with increases in the simultaneous presence of other indicators of nervous system inhibition, specifically, the absence of eye and body movements.
It is argued that these maturational changes could not be adequately explained by current theories. A model of the development of respiratory control is proposed, based on the concept that the neuronal complexity of interaction at each brain level increases at the same time that the hierarchical locus of control moves upward and the interaction between all brain levels becomes more complex.
Newborn - Premature - Respiration - Maturation - Nervous System
