1995 Volume 54 Issue 3 Pages 279-286
Optokinetic training (OKT) is known to improve optokinetic nystagmus (OKN), but little is known about the mechanism. To elucidate the mechanism, we examined the effect of OKT on OKN in pigmented rabbits. The rabbits received OKT (a step stimulus of 30 deg/sec, for 15 min a day) for 3 weeks. The OKN of the rabbits was tested with a step stimulus (1, 2, 5, 10, 20, 30, 45 deg/sec) once a week; we also examined the effect on training of injections of methamphetamine. OKT significantly increased the average steady state gain with the step stimulus but did not significantly change either the time to the steady state or the duration of optokinetic after-nystagmus (OKAN). Metham-phetamine (0.5 mg/kg i.p.) reduced the time to the steady state, before and after the 3-week training period, but did not significantly change the average steady state gain or the duration of OKAN. These results suggest that the oculomotor pathway, except for the velocity storage mechanism, may be responsible for the improvement seen with optokinetic training.
