Andrew W Sills

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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)
Scatter plots showing the amplitude versus velocity (maximum and average) relationship of horizontal saccades in 25 normal subjects and four groups of patients were statistically compared. Three patients with "subclinical" medial longitudinal fasciculus syndromes had significant slowing of adducting saccades, and two of these patients had unsuspected(More)
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°/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)
Nanorod solar cells have been attracting a lot of attention recently, as they have been shown to exhibit a lower carrier multiplication onset and a higher quantum efficiency than quantum dots with similar bandgaps. The underpinning theory for this phenomenon is not yet completely understood, and is still the subject of ongoing study. Here we conduct a(More)
A computer program for analyzing nystagmus has been developed and can be used on a small laboratory digital computer. The algorithm accepts digitized data and looks for the minimum and maximum (minmax) points of the nystagmus waveform. These points in turn are used to define seven descriptive parameters of nystagmus, including the amplitude, duration, and(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)
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)
Results of bithermal caloric testing in 83 patients with unilateral peripheral vestibular disease, cerebellopontine angle tumors and vertebrobasilar insufficiency were compared in order to find which response measurements identified the most abnormal responses in each disease category. A laboratory digital computer was used to quantitatively assess each(More)