A neurobiological model for the effects of early brainstem functioning on the development of behavior and emotion regulation in infants: implications for prenatal and perinatal risk.
CNS-compromised neonates are poor modulators tending to prefer less stimulation in all arousal conditions. Cocaine-exposed neonates also are poor modulators but tend to prefer more stimulation in all arousal conditions. Infants (N = 359, M = 4 months) were divided into 6 CNS injury groups and 1 cocaine-exposed, non-CNS-injured group and tested in three arousal conditions: less aroused (after feeding), more around-endogenous (before feeding), and more aroused-exogenous (after feeding with additional stimulation prior to each trial). Infants with CNS injuries still showed some degree of influence of arousal on attention that was now similar to that seen in normal neonates and 1-month-olds, while cocaine-exposed infants, 4-month-old normal and mild or moderate CNS-injury infants did not.