Comparison of the slow phase velocity of nystagmus with and without vision correction

Two exposure sessions consisted of 5 minutes in the optokinetic drum rotating clockwise at 35 degrees per second (slightly greater than the 5 r.p.m. used in previous experiments). Subjects viewed the drum with their spectacles or contact lenses on for one session, followed by a 20 minute rest period, then viewed the same optokinetic stimulation without their spectacles or contact lenses. Six subjects commenced viewing with their vision corrected, and seven subjects commenced viewing with their vision uncorrected.