The aim of this study was to discover finger interaction indices during single-finger ramp tasks and multi-finger coordination during a steady state force production in two directions, flexion, and extension. Furthermore, the indices of anticipatory adjustment of elemental variables (i.e., finger forces) prior to a quick pulse force production were quantified. It is currently unknown whether th...

Local field potential (LFP) recordings from patients with deep brain stimulation electrodes in the basal ganglia have suggested that frequency-specific activities correlate with force or effort, but previous studies have not been able to disambiguate the two. Here, we dissociated effort from actual force generated by contrasting the force generation of different fingers while recording LFP acti...

The human opposable thumb enables the hand to perform dexterous manipulation of objects, which requires well-coordinated digit force vectors. This study investigated the directional coordination of force vectors generated by the thumb and index finger during precision pinch. Fourteen right-handed, healthy subjects were instructed to exert pinch force on an externally stabilized apparatus with t...

OBJECTIVE To examine the role of practice in the modification of force enslaving and motor-related cortical potentials using finger force production tasks. This study follows-up previous studies in our laboratory using experienced piano players. METHODS Two experiments were performed. In Expt. 1, 6 subjects participated in a pre and post EEG session separated by 12 practice sessions which wer...

The purpose of this study was to examine the factors contributing to hand differences in rapid single finger tapping. To this end, task-defined temporal variables and motor outflow, as reflected by the magnitude and duration of force, were simultaneously measured. Thirty-one right-handed college age subjects performed a rapid finger-tapping task with the index finger of the right and left hands...

The influence of the cerebellum on independent finger control has rarely been investigated. We examined multidigit control in 22 patients with cerebellar degeneration, 20 patients with cerebellar stroke, and 21 patients with surgical lesions after cerebellar tumor removal. In the first task, either the index finger or the middle finger was actively lifted from an object during static holding. B...

Fingertip positions can be conceptualized as Brownian particles within a force field. Using stochastic differential equations (SDEs) the force field and its associated potential function can be formally related to observed fingertip positions. Using observed fingertip positions the force field can then be “solved.” This provides a means of describing, comparing, and simulating finger-movement t...