We measured the eye movements of three sisters with Niemann-Pick type C disease who had a selective defect of vertical saccades, which were slow and hypometric. Horizontal saccades, and horizontal and vertical pursuit and vestibular eye movements were similar to control subjects. The initial movement of oblique saccades was mainly horizontal and most of the vertical component occurred after the...

27 Movement control responsible for generation of maximal hand velocity was 28 studied on the example of horizontal arm swing that is a component of various sports 29 activities. The movement was performed with the non-dominant arm in similarity with 30 the baseball bat swing. The task was to generate maximum hand velocity at a target. The 31 movement included trunk long-axis rotation and horiz...

Reaching in space requires that the target and the hand are represented in the same coordinate system. While studies on visually-guided reaching consistently demonstrate the use of a gaze-dependent spatial reference frame, controversial results exist in the somatosensory domain. We investigated whether effector movement (eye or arm/hand) after target presentation and before reaching leads to ga...

The present study investigated how direction of hand movement, which is a well-described parameter in cerebral organization of motor control, is incorporated in the somatotopic representation of the manual effector system in the human primary motor cortex (M1). Using functional magnetic resonance imaging (fMRI) and a manual step-tracking task we found that activation patterns related to movemen...

A two-dimensional rigid-body model of jaw movement was used to describe jaw opening and closing gestures for vowels and for bilabial and alveolar consonants. Jaw movements were decomposed into three components: (a) rotation about the terminal hinge axis, (b) the horizontal translation of that axis, and (c) the vertical translation of that axis. Data were collected for 3 subjects in two separate...

Remembered saccades of rhesus monkeys are markedly influenced by starting eye position. Altering the initial position systematically affects the direction or amplitude of the movements to a striking degree. In general, changes in the horizontal or vertical starting position primarily produce changes in the horizontal or vertical component, respectively, regardless of whether the target displace...

Short- and long-term consequences of canal plugging on gaze shifts in the rhesus monkey. I. Effects on gaze stabilization. To study the contribution of the vestibular system to the coordinated eye and head movements of a gaze shift, we plugged the lumens of just the horizontal (n = 2) or all six semicircular canals (n = 1) in monkeys trained to make horizontal head-unrestrained gaze shifts to v...

Lesions that involve the paramedian pontine reticular formation (PPRF) or the sixthnerve nucleus on one side of the brain stem and also interrupt internuclear fibers of the ipsilateral medial longitudinal fasciculus produce an ipsilateral horizontal gaze palsy combined with an internuclear ophthalmoplegia, so that the only preserved horizontal eye movement is abduction of the contralateral eye ...

In everyday life, we frequently alternate between performing discrete and rhythmic movements. When performing a periodic movement, two distinct movement types can be distinguished: highly harmonic vs. discrete-like. The harmonicity of the movement is used to classify it as one or the other. We asked: (1) whether the frequency at which a periodic movement is performed affects the harmonicity of ...