| Objective: To explore the effects of electroacupuncture (EA) on the facilitation of the reticulospinal tract and anticipatory postural adjustment (APA) in stroke patients via startle-activating reaching tests. Methods: All 13 stroke patients received startle-activating reaching tests based on sEMG before and 20 min after EA (LI4 and LI11). The patients were asked to perform 30 reaching tests with hemiplegia upper limb in the seated position via 80dB (normal) or 114dB (startle) starting sound. The sEMG data of bilateral sternocleidomastoid (SCM) and lower trapezius and anterior deltoid, flexor and extensor carpi radialis (ECR) on the motor side were collected in these tests. In addition, the 114dB tasks were subdivided into SCM+ and SCM－ onset states according to whether the SCM was activated ahead of time. The incidence of the positive StartReact effect (SE) and the premotor reaction time (PRT), the APA onset latency and the amplitude of the muscles at different onset states were used for statistical analysis based on sEMG data processing. Results: The incidence of positive SE was significantly increased (P＝0.048), and the PRT was shortened (P=0.038) after EA. Moreover, the onset latency of extensor carpi radialis at the positive SE state was shortened (P<0.001) and its APA amplitude was increased (P=0.049) after EA. Meanwhile, the onset latency of the contralateral lower trapezius was extended at the negative SE state (P<0.001), and its APA amplitude was reduced at the normal sound (P=0.003) and positive SE state (P=0.01) after EA. Conclusion: The facilitation effects of EA on the reticulospinal tract in stroke patients were demonstrated by enhanced positive response and enhanced anticipatory postural adjustment of forearm muscles. |
