A peculiar aspect of the muscular organization of the human hand is that the main flexors and extensors of the fingers are muscles that each give rise to four parallel tendons that insert on all the fingers. It has been hypothesized that these multi-tendoned muscles are comprised of functional compartments, with each finger controlled by a discrete population of motor units. The purpose of this...

A method for controlling the grasping force when an object is grasped by artificial elastic fingers is proposed. First, the relationship between the stick area and the internal strain distribution of the finger is calculated using FE (finite element) analysis. Based on this relationship, a method is proposed for controlling the grasping force by decreasing the increasing ratio of the tangential...

The purpose of the study was to present a method for the assessment of finger joint torques in two-fingered precision grips. The static analysis of various grips is important for the analysis of the mechanics of a human hand and the functional evaluation of grasping. We have built a grip-measuring device assessing the endpoint forces of two-oppositional grips. Through the simultaneous use of an...

Skilled piano performance requires considerable movement control to accomplish the high levels of timing and force precision common among professional musicians, who acquire piano technique over decades of practice. Finger movement efficiency in particular is an important factor when pianists perform at very fast tempi. We document the finger movement kinematics of highly skilled pianists as th...

Using transcranial magnetic stimulation (TMS), we examined whether sensory input from a finger affects activity of the ipsilateral primary motor cortex (M1) when human subjects hold a virtual object bimanually and whether this ipsilateral activation varies under different contexts. Subjects used both index fingers to hold two plates, which were subjected to unpredictable pulling loads from torq...

BACKGROUND Grip size of a tennis racquet has been reported to influence performance, but clear evidence of a correlation has yet to be established. HYPOTHESIS Hitting force during a soft tennis forehand stroke correlates with grip size. STUDY DESIGN Controlled clinical study. METHODS A total of 40 healthy volunteers (20 men and 20 women) with a mean age of 21.9 years were enrolled. Of the...

Variability of motor output often has been considered a form of noise that interferes 2 with reliable performance. This assumption, however, depends on the level of the 3 motor system under consideration. For targeting tasks, variability of the end-effector 4 position will affect the consistency of targeting, depending on the task requirements 5 and the size of the target. Variability of coordi...