Abstract
The horizontal vestibulo-ocular reflex (VOR) has been recorded electrooculographically
in normal infants aged from one to four weeks and in older subjects submitted to sinusoidal
oscillations (± 15°, 0.05 -0.5 Hz) in the dark. The analysis of the dynamic characteristics
of the reflex indicates that, at least in the low frequency range, the VOR has not
yet attained a truly compensatory role in the first month of life. In two of the subjects
the VOR has been followed throughout the second month of life. At this age the phase
of the reflex has already developed the characteristics of the comparison-group at
all the frequencies of stimulation, while the trend of the amplitude modulation has
not yet changed from the newborn stage. By the 6th month of life the VOR characteristics
are comparable with those present in the comparison-group. It appears therefore that
the horizontal VOR undergoes a process of maturation during the early period of life,
which affects in different times both phase and amplitude values. The possible role
exerted by different neural structures on this maturation process is discussed.
Key words
Vestibulo-ocular reflex - Dynamic characteristics - Natural vestibular stimulation
- Early development
