The effects of early vestibular deprivation on the motor development in the rat.

The motor development after uni- or bilateral vestibular deprivation from the 5th or 16th postnatal day was studied in 23 rats between the 6th and the 60th day. Their motor behaviour was compared to that of 17 normal rats. Vestibular deprivation from the 5th day causes a marked retardation in motor development. Our results suggest that this retardation is caused by non-optimal stabilization of the trunk during development. Vestibular deprivation from the 16th day causes only short lasting disturbances of motor behaviour for one or two days. The main permanent effect of bilateral vestibular deprivation is head oscillation during locomotion. The temporal organization of the motor behaviour of rats bilaterally deprived from the 5th day was disturbed as well. These rats show more bouts of locomotion, rearing and pivoting.