ABSTRACT
Transcranial magneto-acoustic electrical stimulation (TMAES) is a novel method of brain nerve regulation and research, which uses induction current generated by the coupling of ultrasound and magnetic field to regulate neural electrical activity in different brain regions. As the second special envoy of nerve signal, calcium plays a key role in nerve signal transmission. In order to investigate the effect of TMAES on prefrontal cortex electrical activity, 15 mice were divided into control group, ultrasound stimulation (TUS) group and TMAES group. The TMAES group received 2.6 W/cm 2 and 0.3 T of magnetic induction intensity, the TUS group received only ultrasound stimulation, and the control group received no ultrasound and magnetic field for one week. The calcium ion concentration in the prefrontal cortex of mice was recorded in real time by optical fiber photometric detection technology. The new object recognition experiment was conducted to compare the behavioral differences and the time-frequency distribution of calcium signal in each group. The results showed that the mean value of calcium transient signal in the TMAES group was (4.84 ± 0.11)% within 10 s after the stimulation, which was higher than that in the TUS group (4.40 ± 0.10)% and the control group (4.22 ± 0.08)%, and the waveform of calcium transient signal was slower, suggesting that calcium metabolism was faster. The main energy band of the TMAES group was 0-20 Hz, that of the TUS group was 0-12 Hz and that of the control group was 0-8 Hz. The cognitive index was 0.71 in the TMAES group, 0.63 in the TUS group, and 0.58 in the control group, indicating that both ultrasonic and magneto-acoustic stimulation could improve the cognitive ability of mice, but the effect of the TMAES group was better than that of the TUS group. These results suggest that TMAES can change the calcium homeostasis of prefrontal cortex nerve clusters, regulate the discharge activity of prefrontal nerve clusters, and promote cognitive function. The results of this study provide data support and reference for further exploration of the deep neural mechanism of TMAES.
Subject(s)
Animals , Mice , Acoustics , Brain , Calcium , Electric Stimulation , Prefrontal Cortex , Transcranial Direct Current Stimulation , Transcranial Magnetic StimulationABSTRACT
Objective To assess the reaching ability of hemiplegic stroke survivors using a motion capture unit (MCU) combined with surface electromyography (sEMG).Methods Sixteen stroke survivors with hemiplegia formed the experimental group,while healthy counterparts were selected as the control group.Both groups were asked to sit on a chair and reach for a cup on a table in front of their shoulder at arm's length using their affected arms in the experimental group and their right arms in the control group.MCUs were fixed on their spines and arms to obtain kinematic signals,and the sEMG signals of the trapezius,the anterior deltoids,biceps and triceps of the tested limb were recorded.Each subject repeated the test 3 times,and the best result was retained for further analysis.After signal processing,the range of movement of the shoulders and elbows was extracted along with the time used to reach the cup,peak angular velocity,time to peak velocity of the shoulders and elbows,work of the muscles and work ratios of the trapezius/deltoid and biceps/triceps.The upper limb section of the Fugl-Meyer assessment (FMA) was also administered to evaluate the patients' upper limb function.Independent sample rank sum tests compared the patients with the controls in terms of kinematics and sEMG parameters.Spearman analysis was used to explore the correlation between the FMA scores and the kinematics and sEMG characteristics.Results Significant differences in the kinematic and myoelectric indicators were found between the patients and the controls.The average FMA score of the patients was correlated with the peak velocity of the shoulder joint.Moreover,the ROM of the shoulder was closely related to the work of the trapezius,while the time for the shoulder joint to reach peak velocity was closely related to the work ratio of the biceps and triceps.Conclusion An MCU integrated with synchronous sEMG can quantitatively assess the kinematics and kinetics of hemiplegic stroke survivors,at least in reaching.This can provide objective guidance to optimize clinical rehabilitation.
ABSTRACT
Objective To evaluate the feasibility of using a microsensor motion capture unit (MCU) to assess the reaching characteristics of hemiplegic stroke patients. Methods Twenty-three hemiplegic stroke patients with an average age of (61 ± 11) years and ten normal subjects of matching age were asked to sit on a chair and use the affected arm (for the patients) or the right arm (for the normal subjects) to reach for a cup on a table just in front of the shoulder at arm's length away.Four small sensor boxes which could detect movement and its speed and smoothness in three dimensions were fixed to the subject's spine,upper arm,forearm and hand.The test was repeated four times after two trial runs.The average velocity,peak velocity,degree of joint dispersion,entropy of acceleration,joint coordination and active range of motion ( AROM ) of the shoulder were analyzed.The patients and normal subjects were statistically compared.The results were correlated with Fugl-Meyer upper extremity scores using Spearman correlation analysis. Results All of the measured variables showed significant differences between the patients and normal subjects.In the correlation study,the average velocity,peak velocity,AROM of the shoulder and joint coordination showed significant correlation with the Fugl-Meyer scores.There was,however,no significant correlation between degree of dispersion of the shoulder or elbow joints or the entropy of acceleration ( which represented the quality of movement) and Fugl-Meyer upper extremity scores. Conclusions The results suggest that microsensor MCUs can quantitatively assess the kinematics of reaching among hemiplegic stroke patients.They can provide valuable and objective data about the functional quality of multiple joint movements in three dimensions.