| The application of motor imagery in motor function rehabilitation has been a research hotspot in recent years.Motor imagery has a great overlap with the brain areas activated by actual motor activities.It can be used as an adjuvant therapy for repairing and reconstructing damaged motor conduction pathways.Its efficacy has been obtained.certain clinical validation.Neural activity can be observed with techniques such as electroencephalogram(EEG)and functional magnetic resonance imaging(f MRI).Functional magnetic resonance imaging has high spatial resolution,and its spatial resolution increases with the increase of magnetic field strength;the magnetic resonance imaging signal is based on the complex BOLD effect,which can convert neural activity,intravascular changes and magnetic resonance into magnetic resonance imaging.Signals are linked,but the BOLD effect often lags neural activity by a few seconds.In order to deeply study the neural activity mechanism of motor imagery after amputation,EEG technology with high temporal resolution in milliseconds can observe the neural activity process of motor imagery after amputation in real time.EEG signal is a physiological signal of brain electrical activity collected by EEG equipment.It is formed by the summation of post-synaptic potentials that occur synchronously by a large number of neurons.The EEG signal excited by task induction can be observed in real time after effective processing.Basic processes of neural activation in task states.In this experiment,E-Prime software was used to design the lower extremity motor imagery experimental paradigm.The EEG data of 14 patients with unilateral left lower limb amputation and 20 healthy subjects were collected.Event-related desynchronization/synchronization(ERD/ERS)analysis studies the effect of amputation on neural activity during motor imagery.Resting-state EEG microstate analysis evaluates large-scale cortical activity in the whole brain after amputation.The event-related potential study showed that the ERP peaks evoked by motor imagery in the two groups were concentrated in the 250-350 ms time range,and the ERP peak in the amputation group was higher than that in the healthy control group.The alpha frequency band(8-12Hz)and beta frequency band(13-20Hz)have obvious ERD phenomenon,but this phenomenon does not appear in the amputation group;the resting-state EEG microstate study shows that the duration of microstate C in the amputation group is the frequency of occurrence of microstate B and microstate D was significantly different from that of healthy controls.According to the differences in EEG signals between the lower limb amputation group and the healthy control group in the resting state and motor imagery state,the amputation group requires more neural activity to complete the lower limb motor imagery than the healthy control group,and amputation promotes neuroplasticity and change the EEG neural patterns of motor imagery task state and resting state.EEG technology can deepen the understanding of neural activity after lower extremity amputation,and provide a theoretical basis for establishing benign remodeling from limb to brain. |
