Developmental course of general movements in early infancy. I. Descriptive analysis of change in form.

In order to describe the developmental changes of general movements (GM) in early infancy and to relate them to changes in other aspects of the neurological repertoire, the spontaneous motility in supine position was recorded on video tape at 4-week intervals in a group of twenty-two full-term healthy infants aged 2-18 weeks. Each follow-up session included a neurological examination. In newborn infants GM have a 'writhing' quality. The movements are characterized by a tight appearance, a relatively slow speed and a limited amplitude. The 'writhing' character of the GM is gradually broken down into a so-called 'fidgety' quality. These GM are typified by an ongoing flow of small movements occurring irregularly all over the body. The transformation of GM from a 'writhing' character into a 'fidgety' character was related more closely to postmenstrual than to postnatal age. 'Fidgety' GM were almost constantly present at the age of 8-12 weeks. In the third month very rapid arm movements ('swipes' and 'swats') occurred. The developmental changes in the form of the GM and those of the neurological repertoire showed no significant correlation. This demonstrates that within the normal CNS the various functional modules develop autonomously.