Reorganization of the frequency map of the auditory cortex evoked by cortical electrical stimulation in the big brown bat
Reorganization of the frequency map of the auditory cortex evoked by cortical electrical stimulation in the big brown bat
复制标题
DOI：
10.1152/jn.2000.83.4.1856
复制
发表时间：
2000-04-01
影响因子：
2.5
通讯作者：
Suga, N
中科院分区：
文献类型：
--
作者：
Chowdhury, SA;Suga, N
在回声定位的搜索阶段，大棕色蝙蝠，Eptesicus fuscus，以每秒10次的速度发射生物声纳脉冲并倾听回声。当以这种频率重复传递一个短的声刺激时，初级听觉皮层的频率图的重组发生在与声刺激频率调谐的神经元及其周围。当声刺激与调谐到声刺激频率的皮层神经元的电刺激配对时，这种重组变得更大。这种重组主要是由于神经元的最佳频率降低，这些神经元的最佳频率略高于电刺激皮层神经元的最佳频率或声刺激的频率。神经元的最佳频率略低于那些声学和/或电刺激的神经元略有增加其最佳频率。这些变化导致重复传递的声刺激的过度表现。由于过度表征导致其他频率的表征不足，这些变化增加了听觉刺激的神经表征的对比度。最好的频率偏移与25%的神经元研究的频率调谐曲线的锐化。由于神经表征的对比度和调谐的锐度的增加，声刺激的过度表征伴随着对声刺激的分析的改善。
In a search phase of echolocation, big brown bats, Eptesicus fuscus, emit biosonar pulses at a rate of 10/s and listen to echoes. When a short acoustic stimulus was repetitively delivered at this rate, the reorganization of the frequency map of the primary auditory cortex took place at and around the neurons tuned to the frequency of the acoustic stimulus. Such reorganization became larger when the acoustic stimulus was paired with electrical stimulation of the cortical neurons tuned to the frequency of the acoustic stimulus. This reorganization was mainly due to the decrease in the best frequencies of the neurons that had best frequencies slightly higher than those of the electrically stimulated cortical neurons or the frequency of the acoustic stimulus. Neurons with best frequencies slightly lower than those of the acoustically and/or electrically stimulated neurons slightly increased their best frequencies. These changes resulted in the overrepresentation of repetitively delivered acoustic stimulus. Because the over-representation resulted in under-representation of other frequencies, the changes increased the contrast of the neural representation of the acoustic stimulus. Best frequency shifts for over-representation were associated with sharpening of frequency-tuning curves of 25% of the neurons studied. Because of the increases in both the contrast of neural representation and the sharpness of tuning, the over-representation of the acoustic stimulus is accompanied with an improvement of analysis of the acoustic stimulus.