http://worldcat.org/entity/work/id/15471225

Primary, secondary, and caloric nystagmus of the cat following habituation to rotation

Ten cats were exposed to a series of abovethreshold accelerations and sub-threshold deceleration. Unilateral caloric irrigations, provoking nystagmus in the same direction as the above-threshold rotational stimuli preceded and followed the set of accelerations. A marked adaptation of nystagmus, characterized by specific changes in early trials, resulted from repeated rotation. Although neither duration nor total slow-phase eye displacement to caloric stimulation was affected, the intervening rotational experience produced some reduction in the frequency of the nystagmic beats. Two factors were proposed in explanation for the minimal transfer of adaptation from the rotational to the caloric situation. Secondary nystagmus activity was also examined and appeared closely related to preceding primary reactions. The data indicate that clinical (caloric) responses to vestibular stimulation may not give an accurate indication of a subject's state of adaptation to practiced levels of angular accelaration. Such findings provide cautions in the establishment of appropriate testing techniques for the analysis of vestibular function in air-or spacevehicle crew members. (Author).

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