Further evidence for corticomotor hyperexcitability in amyotrophic lateral sclerosis

摘要: A collision experiment has been used to investigate repetitive firing of first dorsal interosseous motoneurons following a single transcranial magnetic stimulus (TMS) in healthy subjects and patients with amyotrophic lateral sclerosis (ALS). An appropriately timed supramaximal peripheral nerve shock blocks the descending impulses motor axons allows response due be quantified. Multiple increases as TMS intensity rises saturates at about 1.25 times threshold. Increasing background force also augments levels above 50% maximum. The ratio area attributed motoneuron initial direct was compared 10 ALS controls. In patients, significantly higher (P = 0. 0005), indicating greater degree motoneurons. This suggests that, ALS, there is corticomotor hyperexcitability either spinal or cortex.