Search results for "Postural tremor"
showing 2 items of 2 documents
Effects of wrist oscillations on contralateral neurological postural tremor using a new myohaptic device ('wristalyzer')
2007
Upper limb postural tremor consists of distinct oscillations, mainly mechanical-reflex and central-neurogenic. These oscillations are superimposed upon a background of irregular fluctuations in muscle force. Muscle spindles play key-roles in the information flow to supra-spinal and spinal generators. Oscillations were delivered using a new generation portable myohaptic device, called 'wristalyzer', which takes into account the ergonomy of upper limbs allowing a fine adjustment to each configuration of upper limb segments. The nominal torque of the device is 4 Nm, with a maximal rotation velocity of 300 degrees/s and a range of motion of +45 to -45 degrees. Reliability was assessed in basal …
Quantifying the contribution of arm postural tremor to the outcome of goal-directed pointing task by displacement measures.
2004
A method for quantifying the outcome of goal-directed postural pointing was presented and used for relating the tremor output to the oscillations of single arm landmarks. The displacement of reflective markers placed on shoulder, upper arm, forearm, and hand were measured by an optoelectronic motion capture system in nine subjects holding a laser penlight pointed at a target. The high signal-to-noise ratio of the measured displacement series (from 7:1 for shoulder marker to 30:1 for hand marker) demonstrated the feasibility of the proposed system to carry out tremor analysis. The track of the laser emission on the target, reconstructed from penlight displacements, was studied as the outcome…