We review experiments supporting the hypothesis that the vertebrate motor system produces
movements by combining a small number of units of motor output. Using a variety of …

In order to investigate the strategies used to plan and control multijoint arm trajectories, two-degrees-of-freedom
arm movements performed by normal adult humans were recorded. …

To execute voluntary movements, the central nervous system must transform the neural
representation of the direction, amplitude, and velocity of the limb, represented by the activity of …

Learning is more than memory. It is not simply the building of a look-up table of labelled
images, or a phone-directory-like list of motor acts and the corresponding sequences of muscle …

LEARNING a motor skill sets in motion neural processes that continue to evolve after practice
has ended, a phenomenon known as consolidation 1–4 . Here we present psychophysical …

… where the denominator and numerator of this expression correspond respectively to the
positive term and the absolute value of the negative term in the expression for the gradient of E 2 …

When the hand is displaced from an equilibrium posture by an external disturbance, a force
is generated to restore the original position. We developed a new experimental method to …

One hypothesis for the generation of spatially oriented arm movements by the central nervous
system is that a desired joint position is determined by the ratio of the tensions of agonist …

1. The experiments described here are addressed at identifying some of the processes
underlying arm movements in monkeys. 2. We used three adult monkeys that were trained to …

Selecting the appropriate muscle pattern to achieve a given goal is an extremely complex
task because of the dimensionality of the search space and because of the nonlinear and …