Abstract
The developmental change of spontaneous hand movements were investigated longitudinally in 5 lowrisk pre-term infants. The observation period was divided into three: 33-40, 41-52 and 53-60 weeks in order of gestational age. Both hand-mouth contacts (H-M-C) and hand-face contacts (H-F-C) were frequent in the 33-40-week period, and decreased drastically in the 41-48 week period. In the 53-60- week period, the number of H-F-C remained at a low level, while H-M-C increased again to the level of the first period. Furthermore, the mouth was open as the hand came into contact with it as frequently in the 33-40-week period as in the 53-60-week period. These findings suggest that H-M-C are neurologically distinct from HF-C, and that the H-M-C before 41 weeks and after 50 weeks share some common components of this neurological mechanism.