The development of motor activity: observing spontaneous behavior in fetuses, preterm and term infants

Nowadays, ultrasound examinations in 3D and 4D are promoting the concept of continuity in human motor behavior. The most recent studies on the central nervous have focused both on the general movements of the body and on facial expressions, in order to identify additional evaluation criteria to understand the neuro-behavioral development. The aim of this study is to observe spontaneous motor behavior from the beginning of movement during prenatal life. The observation of human motor behavior is related to the normal function of central nervous system and it can detect early, or even before birth, the integrity of central nervous system (Di Pietro, 2005). In order to describe spontaneous behavior before and after birth, we are going to dedicate the first experiment to code spontaneous motor activity in a group of fetuses and preterm infants at the same gestational age. To code behavior we adopted a new coding scale made by 21 behavioral motor patterns, deriving from the descriptive categories of behavior observed in fetuses, preterm and full-term infants. Comparison between preterm infants and fetuses at the same gestational age was allowed to understand the ontogeny of spontaneous motor activity, but it also helped us to highlight the differences in behavior from the prenatal period to postnatal life. In the second experiment we investigate how appetite condition, as a primary motivational factor, modulates behavior in premature newborns. Results suggest that we can find a modulation in behavior expression also during preterm development and that this modulation is functional to attention seeking and to nutrition. The third experiment compares behavior between full-term and preterm newborns at the same post-conceptional age. Results state there are differences in behavioral motor patterns, as a result of the different behavioral state regulation and coming from the different types of maturational and environmental development. Thanks to these experiments we can confirm that our new behavioral motor patterns coding scale is sensitive to behavior exhibited by fetuses, preterm and full-term infants. Spontaneous behavior is an activity endogenously generated by the CNS which reflects the state of neural development. Behaviors is sensitive to changes in physiological and motivational functions. The study of spontaneous behavior allows us to understand the evolutionary trajectories of specific functions and to inquire into newborn well-being. The value of these observations is twofold, because it opens the way for a new approach both scientific and diagnostic.