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During rapid head rotations, saccades ipsiversive with compensatory vestibulo-ocular reflex (VOR) slow phases may augment the deficient VOR and assist gaze stabilization in space. The present experiments compared these vestibular catch-up saccades (VCUSs) with visually and memory-guided saccades. To characterize VCUSs and their relationship to deficiency of(More)
To determine age-related changes, the initial linear vestibulo-ocular reflex (LVOR) of eight older subjects of mean age 65+/-7 years (mean +/- SD, range 56-75 years) was compared with that of nine younger subjects of mean age 24+/-5 years (range 18-31 years) in response to random transients of whole-body heave (interaural) translation at peak acceleration(More)
To determine age-related changes, the initial horizontal vestibulo-ocular reflex (VOR) of 11 younger normal subjects (aged 20-32 years) was compared with that of 12 older subjects (aged 58-69 years) in response to random transients of whole-body acceleration of 1,000 and 2,800 degrees/s2 delivered around eccentric vertical axes ranging from 10 cm anterior(More)
To determine whether dynamic visual acuity (DVA) during head rotations on the stationary body can lateralize unilateral vestibular deafferentation and detect non-labyrinthine compensation mechanisms, 15 normal and 11 subjects with unilateral vestibular deafferentation underwent manually imposed and self-generated transient yaw head rotations during(More)
Magnetic resonance imaging (MRI) now enables precise visualisation of the mechanical state of the living human orbit, enabling inferences about the effects of mechanical factors on ocular kinematics. We used 3-dimensional (3D) magnetic search coil recordings and MRI to investigate the mechanical state of the orbit during vergence in humans. Horizontal(More)
The effect of unilateral vestibular deafferentation (UVD) on the linear vestibulo-ocular reflex (LVOR) was studied in 11 humans an average of 52 months following surgical UVD. Controls consisted of seven healthy age-matched subjects. The LVOR was evoked by directionally random, transient whole body interaural (heave) translation with a peak acceleration of(More)
An ideal vestibulo-ocular reflex (VOR) generates ocular rotations compensatory for head motion. During visually guided movements, Listing's law (LL) constrains eye rotation to axes in Listing's plane (LP). Recently, it has been reported that the VOR axis is not collinear with the rotation axis of the head, but is influenced by eye position in the orbit.(More)
During transient, high-acceleration rotation, performance of the normal vestibulo-ocular reflex (VOR) depends on viewing distance. With near targets, gain (eye velocity/head velocity) enhancement is manifest almost immediately after ocular rotation begins. Later in the response, VOR gain depends on both head rotation and translation; gain for near targets(More)
The vestibulo-ocular reflex (VOR) stabilizes gaze to permit clear vision during head movements. It has been supposed that VOR function might be inferred from dynamic visual acuity (DVA), the acuity during imposed head motion. We sought to determine effectiveness of DVA for detection and lateralization of unilateral vestibulopathy, using rigorous(More)