THE EFFECTS OF EARLY VESTIBULAR DEPRIVATION ON THE MOTOR DEVELOPMENT IN THE RAT

The motor development after uni- or bilateral vestibular deprivation f rom the 5th or 16th postnatal day was studied in 23 rats between the 6 th and the 60th day. Their motor behaviour was compared to that of 17 normal rats. Vestibular deprivation from the 5th day causes a marked r etardation in motor development. Our results suggest that this retarda tion is caused by non-optimal stabilization of the trunk during develo pment. Vestibular deprivation from the 16th day causes only short last ing disturbances of motor behaviour for one or two days. The main perm anent effect of bilateral vestibular deprivation is head oscillation d uring locomotion. The temporal organization of the motor behaviour of rats bilaterally deprived from the 5th day was disturbed as well. Thes e rats show more bouts of locomotion, rearing and pivoting. (C) 1997 E lsevier Science B.V.