The association between dexterity and upper limb impairment during stroke recovery.

Introduction: Stroke-induced upper limb disabilities can be characterized by both motor impairments and activity limitations, commonly assessed using Fugl-Meyer Motor Assessment for Upper Extremity (FMMA-UE) and Action Research Arm Test (ARAT), respectively. The relationship between the two assessments during recovery is largely unstudied. Expectedly they diverge over time when recovery of impairment (restitution) plateaus, but compensation-driven improvements still occur.

Arguments for the biological and predictive relevance of the proportional recovery rule.

The proportional recovery rule (PRR) posits that most stroke survivors can expect to reduce a fixed proportion of their motor impairment. As a statistical model, the PRR explicitly relates change scores to baseline values - an approach that arises in many scientific domains but has the potential to introduce artifacts and flawed conclusions. We describe approaches that can assess associations between baseline and changes from baseline while avoiding artifacts due either to mathematical coupling or to regression to the mean.

What the Proportional Recovery Rule Is (and Is Not): Methodological and Statistical Considerations.

In 2008, it was proposed that the magnitude of recovery from nonsevere upper limb motor impairment over the first 3 to 6 months after stroke, measured with the Fugl-Meyer Assessment (FMA), is approximately 0.7 times the initial impairment ("proportional recovery"). In contrast to patients with nonsevere hemiparesis, about 30% of patients with an initial severe paresis do not show such recovery ("nonrecoverers").

Relating plastic changes of short latency human soleus stretch reflex to changes in task performance induced by training.

Recent findings in the field of neurophysiology showed that operant conditioning on the human H-Reflex is possible. This leads to many possible clinical applications as well as possible sophisticated training methods for athletes. Although stretch reflexes have been subject to extensive literature, knowledge about the influence of short latency stretch reflexes on task performance is lacking.