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The pendulum model of the vestibulo-ocular reflex, including the effects of adaptation, has been evaluated using the responses of 36 normal subjects to impulsive stimuli of 128 and 256 degree/s. Estimates of the model parameters such as the time constants, the slow velocity threshold, and the minimum stimulus required to produce an after-nystagmus have been(More)
A method for rapid, accurate measurement of saccade amplitude, duration, and velocity (average and maximum) was developed as a functional test of the extraocular motor system. Recordings were made with a direct-current electro-oculographic system, and data analysis was performed on a laboratory digital computer. Saccade amplitude and duration were found to(More)
Eye-tracking and optokinetic nystagmus (OKN) abmormalities in patients with focal lesions of the nervous system are reviewed. Patients with peripheral labyrinthine lesions can have deficits in smooth pursuit and OKN, but they are rapidly compensated after an acute lesion. By contrast, patients with large, cerebellopontine angle tumors have progressive(More)
The usefulness of rotatory testing (impulsive and sinusoidal) as an indicator of impaired horizontal semicircular canal function was evaluated in 63 patients with unilateral and bilateral decreased caloric responses. The rotatory stimuli were precisely controlled over a large magnitude range and EOG recorded nystagmus responses were quantified using digital(More)
The impulsive test is brief and comfortable to the patient. The SVM is the best discriminator of the variables examined. By using percent differences between CW and CCW responses in the same subject at the same stimulus magnitude, we can define a range for the normal population and indicate patients outside that normal range. The impulsive test gives(More)
Smooth pursuit eye movements were quantitatively assessed in 25 normal subjects and 22 patients. A laboratory digital computer was used to compute 200 eye velocity samples per second and to statistically compare these eye velocity measurements for five different object velocities. Of six statistics evaluated, mode eye velocity showed the least variability(More)
We have developed an accurate, convenient method for determining unique values of vestibular time constants from impulsive tests. The method was used to determine the mean values and standard deviations of 36 normal subjects. A comparison between these normal values and data from patients with cerebellopontine (CP) angle tumors or unilateral peripheral(More)