RESUMO
OBJECTIVE: Recording the nystagmus of small experimental rodents is an integral technique in vestibular research. Theoretically, the size and the shape of markers strongly affect the analysis of 3 dimensional nystagmus. METHODS: The nystagmus of 6 healthy ICR mice were recorded and their gain values were compared using 200 µm, 300 µm, 400 µm, and 600 µm isosceles triangle markers at the peak velocity of 60°/sec and 100°/sec with the rotational stimulations of 0.1 Hz, 0.2 Hz, and 0.5 Hz. RESULTS: The gain values of 3 different sizes of the markers showed no significant differences in horizontal- vertical-torsional component. However, it was unable to record the nystagmus with 200 µm markers since the markers were too small to be placed and stayed on the center of the pupils. CONCLUSION: Technicians can decide the size of the markers from 200 to 600 µm to record the nystagmus of mice, depending on the technicians' skills.