Smooth pursuit development in infants.
OBJECTIVE
We set out to assess the development of pursuit eye movements in normal infants in an objective, longitudinal fashion. We asked whether smooth pursuit (SP) was present under 2 months of age and how the saccade ratio changed with increasing infant age.


METHODS
Smooth pursuit was recorded longitudinally from 25 infants aged 1-7 months, using DC electro-oculography, in a clinically practical manner. Four uninstructed adults acted as controls.


RESULTS
Smooth pursuit was present under 2 months of age. The gain of SP increased with increasing infant age. However, it had still not reached adult levels by 6 months of age. Latency decreased with increasing infant age. Monocular SP asymmetry was present in the younger infants.


CONCLUSIONS
Smooth pursuit is present under 2 months of age, but at 6 months SP has still not reached adult levels. The traditional model of SP development is questionable.
Jacobs
M
M
Department of Ophthalmology, Great Ormond Street Hospital for Sick Children, London, United Kingdom.
Harris
C M
CM
Shawkat
F
F
Taylor
D
D
D002657:Child Development; D004585:Electrooculography; D019416:Head Movements; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008137:Longitudinal Studies; D011698:Pursuit, Smooth / Q000502:physiology*; D012438:Saccades / Q000502:physiology