Reduced Upper Limb Sensation Impairs Mental Chronometry for Motor Imagery After Stroke: Clinical and Electrophysiological Findings
Neurorehabilitation and Neural Repair, 05/24/2012
Clinical Article
Liepert J et al. – Severe somatosensory deficits impaired mental chronometry. A controlled study is necessary to clarify if these patients benefit at all from Motor imagery as an additional treatment.
Methods- The Box and Block Test (BBT) was used to evaluate mental chronometry as 1 component of MI.
- Two groups of stroke patients and an age-matched healthy control group (CG) were studied.
- Patient group 1 (n = 10, PG1) had a severe somatosensory impairment on the affected side and PG2 (n = 10) had pure motor strokes.
- All subjects first performed the BBT in a mental and in a real version.
- The time needed to move 15 blocks from 1 side of the box to the other was measured.
- To compare the groups independently of their performance level, a (real performance - MI)/(real performance) ratio was calculated.
- Corticospinal excitability was measured by transcranial magnetic stimulation at rest and while the subjects performed an imagined pinch grip.
- The CG performed the BBT faster than both patient groups, and PG1 was slower than PG2.
- MI ability was impaired in PG1 but only for the affected hand.
- Transcranial magnetic stimulation data showed an abnormally low MI-induced corticospinal excitability increase for the affected hand in PG1, but not in PG2.
