Compensation of postural reactions to free-fall in the vestibular neurectomized monkey

摘要

In previous studies a contribution of vision to vestibular-dependent muscle responses during free-fall was found in the intact monkey, and the role of remaining labyrinthine afferents in compensation of these postural reactions was studied in vestibular neurectomized monkeys. In the present investigation we have compared the role of visual motion cues in the recovery of muscle responses to fall in unilateral (U.N.) and bilateral vestibular neurectomized (B.N.) baboons. During free-fall, electromyographic (EMG) responses were recorded from splenius capitis, soleus and tibialis anterior muscles. EMG activities were recorded in two randomly presented conditions: with normal motion of the visual world (NV) and with the visual world stabilized with respect to the baboon's head (SV) until 6 weeks after surgery.