Nonauditory events of a behavioral procedure activate auditory cortex of highly trained monkeys
Nonauditory events of a behavioral procedure activate auditory cortex of highly trained monkeys
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DOI：
10.1523/jneurosci.1571-05.2005
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发表时间：
2005-07-20
影响因子：
5.3
通讯作者：
Scheich, H
中科院分区：
文献类型：
--
作者：
Brosch, M;Selezneva, E;Scheich, H
大脑研究的一个核心原则是，早期感觉皮层是模态特异性的，只有在特殊情况下，如聋哑和失明的受试者或专业音乐家，才会受到其他模态的影响。在这里，我们描述了两只猴子在执行一项要求苛刻的听觉分类任务时，听觉皮层中广泛的跨模态激活：在提示灯打开后，猴子可以通过触摸一个木条来启动一个音调序列，然后在序列中出现下降频率轮廓时释放木条来获得奖励。在他们的初级听觉皮层和后听觉带区域，我们发现许多对声音有反应的神经元，它们的放电与提示光、触碰或释放棒子同步。在315个多单元中，45个表现出与线索光有关的放电，194个表现出与触杆有关的放电，268个表现出与释放杆有关的放电。在60个神经元单元中，我们发现1个神经元具有线索光相关的放电，21个神经元具有杆触相关的放电，36个神经元具有释放相关的放电。当猴子执行视觉检测任务时，这种放电在个别地点消失了。我们的发现证实并扩展了最近关于听觉皮层跨模态激活的发现，并表明听觉皮层可以被视觉和体感刺激以及运动激活。我们推测，听觉皮层的多模态共表征源于被试对行为过程的强化练习，并有助于熟练被试完成听运动任务。
A central tenet in brain research is that early sensory cortex is modality specific, and, only in exceptional cases, such as deaf and blind subjects or professional musicians, is influenced by other modalities. Here we describe extensive cross-modal activation in the auditory cortex of two monkeys while they performed a demanding auditory categorization task: after a cue light was turned on, monkeys could initiate a tone sequence by touching a bar and then earn a reward by releasing the bar on occurrence of a falling frequency contour in the sequence. In their primary auditory cortex and posterior belt areas, we found many acoustically responsive neurons whose firing was synchronized to the cue light or to the touch or release of the bar. Of 315 multiunits, 45 exhibited cue light-related firing, 194 exhibited firing that was related to bar touch, and 268 exhibited firing that was related to bar release. Among 60 single units, we found one neuron with cue light-related firing, 21 with bar touch-related firing, and 36 with release-related firing. This firing disappeared at individual sites when the monkeys performed a visual detection task. Our findings corroborate and extend recent findings on cross-modal activation in the auditory cortex and suggests that the auditory cortex can be activated by visual and somatosensory stimulation and by movements. We speculate that the multimodal corepresentation in the auditory cortex has arisen from the intensive practice of the subjects with the behavioral procedure and that it facilitates the performance of audiomotor tasks in proficient subjects.