Key points Activation of the shoulder abductor muscles in the arm opposite a unilateral brain
injury causes involuntary increases in elbow, wrist and finger flexion in the same arm, a …

Individuals with moderate-to-severe post-stroke hemiparesis cannot control proximal and
distal joints of the arm independently because they are constrained to stereotypical …

Cortical and subcortical plastic reorganization occurs in the course of motor recovery after
stroke. It is largely accepted that plasticity of ipsilesional motor cortex primarily contributes to …

Muscle synergies describe common patterns of co-or reciprocal activation that occur during
movement. After stroke, these synergies change, often in stereotypical ways. The …

Objective The flexion and extension synergies were quantified at the paretic elbow, forearm,
wrist, and finger joints within the same group of participants for the first time. Differences in …

Production of voluntary movements relies critically on the functional integration of several
motor cortical areas, such as the primary motor cortex, and the spinal circuitries …

Patterns of stereotyped muscle coactivation, clinically referred to as synergies, emerge
following stroke and impair arm function. Although researchers have focused on cortical …

An increase in ipsilateral descending motor pathway activity has been reported following
hemiparetic stroke. In axial muscles, increased ipsilateral cortical activity has been …

Following hemiparetic stroke, precise, individuated control of single joints is often replaced
by highly stereotyped patterns of multi-joint movement, or abnormal limb synergies, which …

In humans the two cerebral hemispheres have essential roles in controlling the upper limb.
The purpose of this article is to draw attention to the potential importance of ipsilateral …