The study was undertaken to learn the incidence of unrecognized otological disease in young healthy squirrel monkeys (Saimiri sciureus) maintained under optimum laboratory conditions. No definite pathological changes were found in the middle ears of 20 out of 22 ears examined. Morphologically, all inner ear end organs appeared normal. All threshold caloric test values were within the normal range. No significant variance was noted among the trials. Six out of eleven squirrel monkeys were not susceptible to motion sickness on repeated trials in the Slow Rotation Room. Thus, the lack of susceptibility to motion sickness does not necessarily reflect pathologic suppression of semicircular canal function. (Author).

The study was undertaken to learn the incidence of unrecognized otological disease in young healthy squirrel monkeys (Saimiri sciureus) maintained under optimum laboratory conditions. No definite pathological changes were found in the middle ears of 20 out of 22 ears examined. Morphologically, all inner ear end organs appeared normal. All threshold caloric test values were within the normal range. No significant variance was noted among the trials. Six out of eleven squirrel monkeys were not susceptible to motion sickness on repeated trials in the Slow Rotation Room. Thus, the lack of susceptibility to motion sickness does not necessarily reflect pathologic suppression of semicircular canal function. (Author).