Upper limb movements in the emergence of object cognition.

: Previous studies showed that 40% of fullterm newborns with "anterior plane hypotonia" (APH) neuromotor anomaly present retarded development of object cognition. To understand the possible motor dynamics of this retardation, we studied the principal upper limb movements in a group of normal newborns and in one of APH newborns, with and without stimulus. The total quantity of movement proved to be similar in the two groups but there were differences in the frequencies of the various types of movement, to the detriment in the APH subjects of the movements considered most relevant to object relations. These data underline the importance of the qualitative integrity of newborn movement to the emergence of object cognition.