PhD ceremony Ms. N.K.S. de Vries: Early motor repertoire of infants at risk

PhD ceremony: Ms. N.K.S. de Vries, 16.15 uur, Academiegebouw, Broerstraat 5, Groningen

Dissertation: Early motor repertoire of infants at risk

Promotor(s): prof. A.F. Bos

Faculty: Medical Sciences

Assessment of the quality of the spontaneous motor repertoire has proven to be valid for all infants from birth until 4-5 months as a measure for neurological function (i.e., at a particular moment in time) and neurological outcome.

In this thesis, we assessed the quality of general movements (GMs) and a detailed motor optimality score (OS) in various groups of infants. We found that abnormal GMs during the first days of life are common, both in healthy full term, and in preterm infants. In healthy full term infants normalisation of GM quality occurs from the fifth day after birth onwards. In preterm infants, and even extremely low birth weight infants (ELBW, birth weight <1000gr), we found that having at least one normal GM assessment during the first two weeks of life, was related to a high chance of a normal neurological outcome.

Chaotic features of GMs are seen early in life in several groups of infants. They are probably due to transient destabilisation of the brain and not indicative of permanent brain damage.

At term-equivalent age, we found cramped and stiff movements in ELBW infants, which appeared not to be indicative of an abnormal neurological outcome. Infants who were exposed to an antidepressant agent (SSRI) prenatally, showed neurological effects that reflected a more abnormal GMs with lower OS in the first days after birth. After 3-4 months after term these effects persisted as more monotonous movements; they were independent of maternal mood.