TrkB receptor-dependent PV neurons regulate visual orientation discrimination in mice / 生物工程学报

The neurotrophin-tyrosine receptor kinase B (TrkB) signaling pathway plays an important role in regulating the balance of excitation and inhibition in the primary visual cortex (V1). Previous studies have revealed its mechanism of regulating the level of cortical excitability by increasing the efficiency of excitatory transmission, but it has not been elucidated how TrkB receptors regulate the balance of excitation and inhibition through the inhibitory system, which in turn affects visual cortex function. Therefore, the objective of this study was to investigate how the TrkB signaling pathway specifically regulates the most important inhibitory neuron-PV neurons affects the visual cortex function of mice. The expression of TrkB receptor on PV neurons in the V1 region was specifically reduced by the virus, the functional changes of inhibitory and excitatory neurons in the primary visual cortex were recorded by multi-channel electrophysiological in vivo. The orientation discrimination ability of mice was tested by behavioral experiments, and altered orientation discrimination ability of mice was tested by behavioral experiments. The results showed that reduced expression of TrkB receptors on PV inhibitory neurons in primary visual cortex significantly increased the response intensity of excitatory neurons, reduced the orientation discrimination ability of inhibitory and excitatory neurons, and increased the signal-to-noise ratio, but the orientation discrimination ability at the individual level in mice showed a decrease. These results suggest that the TrkB signaling pathway does not modulate the function of PV neurons solely by increasing excitatory transmission targeting PV neurons, and its effect on neuronal signal-to-noise ratio is not due to enhancement of the inhibitory system.

Comparison of Manual Balance and Balance Board Tests in Healthy Adults

OBJECTIVE: To investigate the correlations of scores on the Timed Up and Go (TUG) test and the Single Leg Stance (SLS) test with stability scores on the Biodex Balance System (BBS) in healthy adults. METHOD: The postural balance of 73 participants was measured on the TUG and SLS tests and with the Overall Stability Index (OSI) on the BBS. The participants were divided into groups by age and by times on the TUG and SLS. The correlations between TUG or SLS and OSI scores were analyzed by groups. RESULTS: TUG scores were significantly correlated with OSI scores in age under 65 years, TUG over 10 seconds and SLS over 30 seconds groups (level 12). TUG scores were also correlated with OSI in total (level 10) and TUG under 10 seconds groups (level 2). However, there were no significant relationships between SLS and OSI scores. CONCLUSION: OSI scores on the BBS are significantly correlated with TUG scores, especially at the easy levels. According to the findings of present study, relatively easy BBS levels are considered to assess the postural balance in healthy adults.

Effects of Balance Visual Feedback Training on Balance Function and Walking Capacity in Patients with Hemiplegia / 中国康复理论与实践

@#Objective To observe the effects of balance visual feedback training on balance function and walking capacity in patients with hemiplegia. Methods40 patients with hemiplegia were divided into the visual feedback group (n=20) and balance board training group (n=20). They were assessed with the Berg Balance Scale (BBS) and the Holden Walking Classification before and 5 weeks after treatment. ResultsThere was no significant difference between groups before treatment in both BBS and Holden Walking Classification (P>0.05). The visual feedback group improved more than the balance board training group (P<0.01). ConclusionThe balancer visual feedback training is more effective on balance function and walking ability in stroke patients with hemiplegia.

The Effects of Biofeedback Balance Training Using InteractiveBalance System in Acute Stroke Patients

OBJECTIVE: To evaluate the effect of the biofeedback balance training using Interactive Balance System (IBS) in acute stroke patients. METHOD: We recruited 40 acute stroke patients who were able to stand independently. The patients were divided into two groups. One group received conventional balance training (control group) and the other group received biofeedback balance training using IBS (case group) for 2 weeks. After training, the effects were evaluated using 3 parameters: indices from IBS (stability score, weight distribution index, and distance form zero point to body's center of pressure (COP) in coordinate), balance assessments (Berg balance scale and postural assessment scale for stroke patients), and functional outcome (the Korean version of modified Barthel index). RESULTS: There were no differences in age and time since onset between the two groups. All parameters were significantly improved in both groups after training. However, the distribution of COP of the case group was significantly closer to the zero point than that of the control group in coordinate after training (p=0.005). CONCLUSION: Biofeedback balance training using IBS has a better effect on the symmetry in static condition on evaluation using IBS than conventional balance training for acute stroke patients.

The Effects of Balance Training Using Balance System in the Hemiplegic Patients

OBJECTIVE: The purpose of this study is to evaluate the balance training effects of balance system in hemiplegic stroke patients. METHOD: The study consisted of 14 male and 6 female hemiplegic patients, aged 48 to 70 years, time postattack ranged from 6 to 17 months. Balance training was done by conventional method (control group) and using balance system (Chattanooga Group, Inc., training group) and the effect were evaluated by balance system. RESULTS: Body sway index and moving target accuracy rate were not significantly different between training group and control group before training, but were significantly different after training. Training group showed significantly decreased sway index and increased moving target accuracy rate at four weeks after training compared to the status before training. CONCLUSION: The hemiplegic patients trained by balance system showed significantly improved static and dynamic postural balance control. Therefore, the balance system is considered to be a valuable training modalitiy for the hemiplegic patients.