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Biomedical subjects

A Tamada

Publications and source records attributed to A Tamada.

57 records · Page 4Linked to original sources
PubMed1981

Dissociation of the eyes in saccadic movement.

In horizontal saccades, abduction and adduction are not conjugate. Abduction starts shortly before adduction and reaches the turning point shortly after abduction. The duration in binocular recording is much shorter than in monocular recordings. The abducting eye has a tendency to move gradually on the new target. The adducting eye has, on the contrary, a tendency to overshoot. The characteristics of quick phases of horizontal optokinetic nystagmus, in which both eyes jump disconjugately to the new target, are similar to those of horizontal saccades. The main cause of this disparity may be a difference in neural mechanisms between abduction and adduction. Vertical saccades are not disconjugate.

Adult↗
PubMedDate not supplied

Modulation of the visuo-ocular reflex by the vestibulo-ocular reflex in peripheral vision.

Peripheral OKN was produced by stimulating the visual field with a special device, designed by Miyoshi et al. Stimuli to induce peripheral OKN and rotatory nystagmus (RN) were applied to the same subject simultaneously. The results obtained were as follows. 1) In the case of the whole visual field, with a target velocity of 30 degrees/sec the combined slow-phase velocity of OKN and RN was also a constant 30 degrees/s in any phase of rotation of the subject and with any combinations of the rotationary directions of subject and target. 2) In the case of the peripheral visual field; when both OKN and RN were in the same direction, the slow-phase velocity of the combined OKN was 10-20% greater than that of the peripheral OKN alone. However, the combined OKN never exceeded the velocity of the target. In contrast, when OKN and RN directions were opposed, combined OKN was correspondingly decreased by about the same 10-20% amount.

Adult↗