Effect of electroacupuncture combined with motor training on motor learning and motor cortex excitability

Abstract

To compare the effect of electroacupuncture (EA), motor training (MT) and EA combined with MT on motor learning and motor cortex excitability in healthy subjects, and to explore the effect of EA combined with MT on synaptic metaplasticity. Using self-control design, 12 healthy subjects were assigned into an EA group, a motor training group (MT group) and an EA plus motor training group (EA+MT group) successively, wash-out period of at least 2 weeks was required between each group. EA was applied at left Hegu (LI 4) in the EA group for 30 min, with continuous wave, 2 Hz in frequency and 0.5-1 mA in density. Motor training of left hand was adopted in the MT group for 30 min. EA and motor training were adopted in the EA+MT group successively. The time of finishing grooved pegboard test (GPT) was observed, and the average amplitude of motor evoked potentials (MEPs), the rest motor threshold (rMT) and the latency were recorded by transcranial magnetic stimulation technique before intervention (T0), after intervention (T1) and 30 min after EA (T3) in the EA group and the EA+MT group, T0 and T1 in the MT group. Compared with T0, the time of finishing GPT was shortened at T1 in the MT group and at T2 in the EA group and the EA+MT group (P<0.01, P<0.05), the average amplitude of MEPs was increased at T1 in the 3 groups and at T2 in the EA group and the EA+MT group (P<0.05, P<0.01). Compared with T1, the time of finishing GPT at T2 was shortened in the EA group and the EA+MT group (P<0.05, P<0.01), the average amplitude of MEPs at T2 was increased in the EA group (P<0.05). The time of finishing GPT at T2 in the EA+MT group was shorter than the EA group (P<0.05). There were no statistical differences in rMT and latency at each time point among the 3 groups (P>0.05). In physiological state, electroacupuncture combined with motor training have a synergistic effect on motor learning, while have no such effect on excitability of cerebral motor cortex.