Supplementary motor area deactivation impacts the recovery of hand function from severe peripheral nerve injury

Although some patients have successful peripheral nerve regeneration,a poor recovery of hand function often occurs after peripheral nerve injury.It is believed that the capability of brain plasticity is crucial for the recovery of hand function.The supplementary motor area may play a key role in brain remodeling after peripheral nerve injury.In this study,we explored the activation mode of the supplementary motor area during a motor imagery task.We investigated the plasticity of the central nervous system after brachial plexus injury,using the motor imagery task.Results from functional magnetic resonance imaging showed that after brachial plexus injury,the motor imagery task for the affected limbs of the patients triggered no obvious activation of bilateral supplementary motor areas.This result indicates that it is difficult to excite the supplementary motor areas of brachial plexus injury patients during a motor imagery task,thereby impacting brain remodeling.Deactivation of the supplementary motor area is likely to be a serious problem for brachial plexus injury patients in terms of preparing,initiating and executing certain movements,which may be partly responsible for the unsatisfactory clinical recovery of hand function.

Functional magnetic resonance imaging evidence for activated functional brain areas following acupoint needling in the extremities

Totally three articles focusing on functional magnetic resonance imaging features of brain function in the activated brain regions of stroke patients undergoing acupuncture on the healthy limbs and healthy controls undergoing acupuncture on the lower extremities are published in three issues. We hope that our readers find these papers useful to their research.

Effects of Repetitive Transcranial Magnetic Stimulation Treatment on Event-Related Potentials in Schizophrenia

Background：Repetitive transcranial magnetic stimulation （rTMS） and event-related potentials （ERPs） are a noninvasive technique that widely used in neurophysiological field.Although rTMS has shown clinical utility for a number of neurological conditions,Recently,there was little understanding of the the efficacy ofrYMS on Schizophrenia（SZ） and the change of ERP between before and after rTMS treatment.The objective of this study was to investigate the characteristics of N400,mismatch negativity （MMN）,and P300 before and after treatment with rTMS in SZ.Methods：One hundred and twenty-seven SZ patients hospitalized in Shanghai Mental Health Center from March 2015 to July 2017,divided into two groups （85 patients were recruited as rTMS group and 42 were recruited as sham rTMS [ShrTMS] group） and 76 normal controls （NCs） who were the staff and refresher staff in our hospital were recruited at the same time.A Chinese-made rTMS and a Runjie W J-1 ERPs instrument were used in the present experiment.N400 was elicited by congruent and noncongruent Chinese idioms.After rTMS treatment,N400,P300,and MMN characteristics were compared with those before treatment and NC group.Results：Compared with NC,the SZ patients exhibited delays in N400,P300,and MMN latency and decreased N400,P300,and MMN amplitudes in their frontal area （P 〈 0.05）.After 25 rTMS treatments,N400 amplitudes in the frontal area （elicited by idioms with same phonic and different shape and meaning and with different phonic,shape,and meaning） were increased in the SZ patients （P 〈 0.05）.However,there was no significant change in N400 before and after treatment with ShrTMS in SZ patients （P 〉 0.05）.Amplitudes for MMN and target P300 also increased in SZ patients after rTMS treatment （P 〈 0.05）.Conclusions：Based on our preliminary findings,we believe that the combined usage of N400,MMN,and P300 could be a valuable index and an electrophysiological reference in evaluating the effects ofrTMS treatment in SZ patients.

Design of Braunbeck Coil for Nuclear Magnetic Resonance Gyro Magnetic Field Excitation

For generating a uniform and steady magnetic field, Helmholtz coil is extensively used in nuclear magnetic resonance gyro(NMRG). Unfortunately, the volume of Helmholtz coil makes it inconvenient to miniaturize NMRG. This study introduces Braunbeck coil that can be used in magnetic field excitation system. Braunbeck coil can produce homogeneous magnetic field within a limit space, and occupy a small volume. In addition, this study presents mathematical expressions that can be used to calculate the area of uniform magnetic field. Experimental test verifies the effectiveness of the proposed design, and the results accord closely with the actual simulation.