Central-peripheral plasticity in sensory impulse conduction

1.无症状周围神经病变的电生理改变我们对糖尿病无症状多神经病变患者进行了电生理改变，其定义为无神经病变症状和踝关节痉挛消失。我们发现81%的患者有两个或两个以上的神经传导参数异常，部分患者中枢传导时间延迟，表明即使在无症状的神经病中也有神经纤维变性。2.躯体感觉皮层高频振荡(HFO)的起源。比较300赫兹以上HFO的等效电流源的偶极方位与N20M的等效电流源的偶极方位。结果表明，HFO和20M电流源的取向不同，且HFO源取向比20M电流源的取向有更大的差异。结果提示，它们可能反映了非锥体神经元群体的活动。3.通过听觉皮层的水平纤维激活等频带。通过测量选择性注意任务中的听觉诱发磁场(AEF)来研究初级听觉皮质的早期认知过程。在音高和侧向辨别任务中，400赫兹和4000赫兹刺激下的N100偶极子强度均增大。400-4000赫兹声调之间的偶极距离在基音辨别任务中较大，但在横向辨别任务中没有变化。我们推测，N100m偶极子的这些动态变化反映了听觉皮质的短期可塑性。

1.Electrophysiological changes in asymptomatic peripheral neuropathy.We performed electrophysiological changes in diabetic patients with asymptomatic polyneuropathy, which was defined as no neuropathic symptom and loss of ankle jerk. We found two or more abnormalities of nerve conduction parameter m 81 percent of the patients Central conduction time was delayed in some patients, indicating degenerating procedd of the nerve fibers even in asymptomatic neuropathy.2.Origin of high frequency oscillation(HFO) in the somatosensory cortex.The dipole orientation of equivalent current source for HFOs above 300Hz and that for the underlying N20m were compared. We found that the orientation of of the HFOs and underlying 20m current source differs and that HFO source orientation shows more divergent pattern than the 20m. The results suggest hat they may reflect activities of the non-pyramidal neuron population.3.Activation of isofrequency bands through horizontal fibers in auditory cortex.Early cognitive process in the primary auditory cortex were studied by measuring auditory evoked magnetic fields(AEF) during selective attention tasks. N100 dipole strength for 400Hz and 4000Hz stimuli was enlarged in both pitch and laterality discrimination tasks. The dipole distance between 400Hz and 4000Hz tones was larger during pitch discrimination task but unchanged during laterally discrimination task. We speculate that these dynamic changes in the N100m dipole reflect short-term plasticity in auditory cortex.