Cervico-ocular responses (COR) during slow sinusoidal head movements in subjects with bilateral labyrinthine lesions

Eye movements in five patients with chronic bilateral labyrinthine loss were tested with sinusoidal movements during cervico-ocular stimulation and active head movements (0.05, 0.1 and 0.2s-1; 20, 40, and 60 degrees) and were compared with healthy subjects. Consideration was given to saccadic activity and slow phase velocity of nystagmus and overall gaze shift. The cervico-ocular response was not altered in the patients. During active pendular head movements the saccadic activity and slow phase velocity of nystagmus were more reduced than the eye shifts. The phase relation of eye shifts was not changed. In our patients neck to eye responses did not compensate for the abolished vestibulo-ocular reflex.