Intervention
stroke, finger movements, Dextrain
STROKE, CONTRACTIONS
A single Dextrain training session consisted of 20 min of conventional training (see below) followed by 40 min of Dextrain exercises (i. finger force-trackingThis task probes visuo-motor force control. The subject is required to precisely generate and modulate fingertip forces in one finger to follow a target force trajectory as closely as possible. The subject gets real-time visual feedback on exerted force (cursor) and matches this to the displayed target force (a line passing from right to left on the screen). Each trial consisted of a ramp-phase (linearly increasing force), a hold-phase (stable 2N force) and a release-phase (instantaneous return to the resting force level), followed by a resting-phase. The abrupt release-phase was conceived to measure (and rehabilitate) ability to stop voluntary contractions, an important aspect of force control that explains additional variance of functional grip capacity [ii. finger motor sequencesThis task was designed to test the capacity to learn a simple finger-tapping motor sequence [iii. rhythm tappingThis task assesses the ability to perform and maintain repetitive finger tapping at frequencies indicated by auditory cues. The subject is instructed to tap, with a single finger, in time (simultaneously) with an auditory cue (beep). Each of the five fingers is tested at three frequencies (1, 2 or 3 Hz). A first period of 30 taps with auditory cue is followed by a period of 30 taps without cue. Previous work showed that stroke patients have greatest difficulty to achieve 3 Hz tapping [iv. independence of finger movementsThis task assesses the ability to perform independent finger movements which are characterized by isolated movement execution (selection) of one finger, while inhibiting movements of neighboring fingers not involved in the trial [