Auditory Cortical Activity after Intracortical Microstimulation and Its Role for Sensory Processing and Learning
Auditory Cortical Activity after Intracortical Microstimulation and Its Role for Sensory Processing and Learning
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DOI：
10.1523/jneurosci.1949-09.2009
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发表时间：
2009-12-16
影响因子：
5.3
通讯作者：
Ohl, Frank W.
中科院分区：
文献类型：
--
作者：
Deliano, Matthias;Scheich, Henning;Ohl, Frank W.
一些研究表明，动物可以学习在行为任务中使用感觉皮层的皮层内微刺激（ICMS）。在这里，我们研究如何通过ICMS的焦点，人工激活导致一个有意义的，行为可解释的信号。在自然学习中，这涉及广泛的大脑网络中的大规模活动模式。因此，我们训练沙鼠区分密切相邻的ICMS网站内的初级听觉皮层产生诱发反应在空间上重叠很大。同时，在训练过程中，我们记录了高空间分辨率的皮层脑电图（ECoGs）。应用多元分类程序，我们确定了后期的空间模式，从正在进行的刺激后ECoG的歧视学习。这些模式包含了关于先前条件刺激的信息，并与动物随后的正确行为反应有关。因此，相关的模式信息主要由ICMS诱发的皮层激活的横向空间扩展范围（类似于1.2 mm）之外的神经元群体携带。这表明，受刺激的皮质区不仅编码信息的刺激部位的局灶性，刺激驱动的激活，但也提供了有意义的信号，在其正在进行的活动有关的解释ICMS学习的动物。这涉及整个受刺激区域，显然需要大脑中的大规模整合。然而，ICMS通过抑制刺激部位附近的图案形成来局部干扰正在进行的皮质动力学。ICMS和正在进行的皮质活动之间的相互作用有几个影响的设计ICMS协议和皮质神经假体，因为有意义的解释ICMS取决于这种相互作用。
Several studies have shown that animals can learn to make specific use of intracortical microstimulation (ICMS) of sensory cortex within behavioral tasks. Here, we investigate how the focal, artificial activation by ICMS leads to a meaningful, behaviorally interpretable signal. In natural learning, this involves large-scale activity patterns in widespread brain-networks. We therefore trained gerbils to discriminate closely neighboring ICMS sites within primary auditory cortex producing evoked responses largely overlapping in space. In parallel, during training, we recorded electrocorticograms (ECoGs) at high spatial resolution. Applying a multivariate classification procedure, we identified late spatial patterns that emerged with discrimination learning from the ongoing poststimulus ECoG. These patterns contained information about the preceding conditioned stimulus, and were associated with a subsequent correct behavioral response by the animal. Thereby, relevant pattern information was mainly carried by neuron populations outside the range of the lateral spatial spread of ICMS-evoked cortical activation (similar to 1.2 mm). This demonstrates that the stimulated cortical area not only encoded information about the stimulation sites by its focal, stimulus-driven activation, but also provided meaningful signals in its ongoing activity related to the interpretation of ICMS learned by the animal. This involved the stimulated area as a whole, and apparently required large-scale integration in the brain. However, ICMS locally interfered with the ongoing cortical dynamics by suppressing pattern formation near the stimulation sites. The interaction between ICMS and ongoing cortical activity has several implications for the design of ICMS protocols and cortical neuroprostheses, since the meaningful interpretation of ICMS depends on this interaction.