The Cortical Motor Effects of PNS and AO on Motor Training in Chronic Stroke

Electrical stimulation was applied to the radial and ulnar nerve (PNS) of the paretic arm for 60 minutes. During the last 30 minutes of PNS, action observation (AO) was introduced in which subjects were required to watch a series of video clips. After one hour's PNS+AO, the subjects then proceeded to a 30-minute period of motor training of paretic hand.

PNS was given as described before. During the last 30 minutes of the PNS, subjects were shown different photos illustrating a letter, a number or a hand as AOsham. The protocol of motor training was the same as described before.

The 1-hour PNSsham was conducted with the electrical stimulation unit turned on but without current output. The protocols for AOsham and motor training were the same as those described before.