Functional Reorganization of Hand-area and Facial-area in Human Motor Cortex after Ischemic Nerve Block
HUANG Jianpeng, LIU Jianhua, JIANG Li
（Guangdong Provincial Hospital，Guangzhou510120，Guangzhou）
Abstract: Objective: By observing the change of motor evoked potentials from Hegu acupoint and ora-facial area in the state of pathology, the object is to probe the mechanism of plasticity in across-representation of the cerebral motor cortex, which provides a basic evidence for the Meridian theory. Method: Transcranial magnetic stimulation was applied to the hand-representation and face-representation in motor cortex before and after the forearm ischemic nerve block. Meanwhile, the electromyography records the motor evoked potentials from the First dorsal interosseus and Orbicularis oculi muscle. Results: 1. The MEPs from First dorsal interosseus: the latentperiod is 20.76±0.45 ms,the amplitude is 535.26±1.25 uV, the Motor threshold is 52.83±9.17%; the MEPs from Orbicularis oculi muscle: the latentperiod is 8.28±0.23 ms,the amplitude is 130.65±0.25 uV, the Motor threshold is 60.0±10.4 %; 2. In pathological conditions, the block of time is 40.61±3.60 minutes.With times’ extending, the area of hand-representation is narrowing.3. The latentperiod and the amplitude are significantly relative to the time of blocking. To dislodge ischemic nerve block, the hand area are recovered. Conclusion：After INB, the MEPs from the target muscles show the changes of the amplitude and the amounts of the stimulated points. It may be one of the biological mechanism of “the specific relation of ora-facial area and Hegu acupoint” in physiological condition.
Key words Acupuncture and moxibustion, the specific relation of ora-facial area and Hegu acupoint, transcranial magnetic stimulation, ischemic nerve block, functional reorganization