Neurobehavioral organization of the newborn: opportunity for assessment and intervention.

A functional model has been formulated that attempts to specify the behavioral subsystems of functioning that exemplify in their respective interplay an infant's individuality of behavioral functioning in the manner in which they move from stable to disorganized functioning and in the flexibility with which they maintain organized functioning in the face of varied exogenous and endogenous events. Based on this model, Als and colleagues have attempted to develop systematic assessments, the APIB and the K-Box Paradigm, to quantify the degree of differentiation and modulation of these behaviorally defined subsystems of functioning. It is hypothesized that the differences documented via these assessments are brain based (i.e., part of the child's biological makeup, which is influenced by the intrauterine and extrauterine environment, be it sensory and/or drug exposure, and which shows a recognizable pattern along a definable trajectory).