Evolution du reflexe de clignement pendant les trois premieres annees de la vie chez l'enfant

Abstract

The blink reflex was elicited in 42 awake and quiet children from birth to 3 years of age. The R1 ipsilateral reflex response was always recorded. Its latency decreased significantly during the first 6 months of life whereas the VIIth nerve motor conduction velocity increased markedly; its threshold stimulus was lower in children after 1 year of age. R2 responses, especially contralateral ones, were sometimes absent in infants under 9 months of age; beyond that age, they were constant and bilateral. The ipsilateral R2 latency response diminished during the first 6 months of life, and the R2 reflex threshold became lower in infants above 1 year of age. When elicited after crying, in 22 children, the reflex components were facilitated; R1 response occasionally appeared bilaterally, its amplitude increased and its threshold was lower. During REM sleep, in 12 children, the reflex responses were similar to those recorded during quiet wakefulness. On the contrary, non-REM sleep recorded in 12 children markedly depressed the reflex responses; this inhibition was more pronounced for R2 responses.