Shifts in coding properties and maintenance of information transmission during adaptation in barrel cortex.
Shifts in coding properties and maintenance of information transmission during adaptation in barrel cortex.
复制标题
DOI：
10.1371/journal.pbio.0050019
复制
发表时间：
2007-02
期刊：
影响因子：
9.8
通讯作者：
Diamond ME
中科院分区：
文献类型：
--
作者：
Maravall M;Petersen RS;Fairhall AL;Arabzadeh E;Diamond ME
在许多系统中，神经元对持续刺激的反应会随着时间的推移而变化，或者说是“适应”。尽管适应无处不在，但它对神经元携带的刺激信息的影响往往是未知的。在这里，我们研究适应如何影响桶皮质中的感觉编码。我们在麻醉大鼠中记录了单个神经元对连续的、快速变化的触觉运动刺激反应的尖峰触发协方差分析。刺激统计数据的变化导致了数百毫秒内的尖峰频率适应。Vibrissa运动编码随自适应改变如下。在每个表现出速率适应的神经元中，输入输出调谐功能随着刺激分布的变化而变化，使神经元能够保持传递的关于刺激特征的信息量。没有表现出速率适应的单个神经元也缺乏输入-输出重新调整，并且不能在刺激统计数据的变化中保持信息。因此，在桶状皮质中，相对于驱动棘波的特征，速率适应发生在一个较慢的时间尺度上，并与与刺激分布匹配的增益重新定标相关。我们的结果表明，适应增强了初级躯体感觉皮层中的触觉表征，在那里它们可以直接影响知觉决策。神经元对持续刺激的反应会随着时间的推移而改变，或者说是“适应”。适应对我们大脑成功表现环境的能力至关重要：例如，当我们从昏暗的场景转移到明亮的场景时，适应调整神经元对给定的光强度的反应，使它们对当前范围的刺激变化最敏感。我们分析了适应如何影响大鼠躯体感觉“桶”皮质的感觉编码，该皮层代表被老鼠的胡须或触须触摸的物体。胡须赋予这些夜间活动的动物令人印象深刻的辨别能力：老鼠可以像我们用指尖区分一样精细地辨别质地的不同。躯体感觉皮层中的神经元通过对“运动特征”，特别是速度波动做出反应，来代表胡须的振动。我们记录了桶状皮质神经元对精心控制的胡须运动的反应，并慢慢改变了运动的总体特征，以提供不断变化的刺激“背景”。我们发现，刺激-反应关系以一种特殊的方式变化：根据当前刺激分布，预测神经元对胡须运动波动的反应的“调谐函数”。重新调整比例正好足以维持有关刺激措施的反应所传达的信息。大脑皮层神经元适应刺激输入统计数据的变化，这表明适应增强了对刺激的辨别和感知。
Neuronal responses to ongoing stimulation in many systems change over time, or “adapt.” Despite the ubiquity of adaptation, its effects on the stimulus information carried by neurons are often unknown. Here we examine how adaptation affects sensory coding in barrel cortex. We used spike-triggered covariance analysis of single-neuron responses to continuous, rapidly varying vibrissa motion stimuli, recorded in anesthetized rats. Changes in stimulus statistics induced spike rate adaptation over hundreds of milliseconds. Vibrissa motion encoding changed with adaptation as follows. In every neuron that showed rate adaptation, the input–output tuning function scaled with the changes in stimulus distribution, allowing the neurons to maintain the quantity of information conveyed about stimulus features. A single neuron that did not show rate adaptation also lacked input–output rescaling and did not maintain information across changes in stimulus statistics. Therefore, in barrel cortex, rate adaptation occurs on a slow timescale relative to the features driving spikes and is associated with gain rescaling matched to the stimulus distribution. Our results suggest that adaptation enhances tactile representations in primary somatosensory cortex, where they could directly influence perceptual decisions. Neuronal responses to continued stimulation change over time, or “adapt.” Adaptation can be crucial to our brain's ability to successfully represent the environment: for example, when we move from a dim to a bright scene adaptation adjusts neurons' response to a given light intensity, enabling them to be maximally sensitive to the current range of stimulus variations. We analyzed how adaptation affects sensory coding in the somatosensory “barrel” cortex of the rat, which represents objects touched by the rat's whiskers, or vibrissae. Whiskers endow these nocturnal animals with impressive discrimination abilities: a rat can discern differences in texture as fine as we can distinguish using our fingertips. Neurons in the somatosensory cortex represent whisker vibrations by responding to “kinetic features,” particularly velocity fluctuations. We recorded responses of barrel cortex neurons to carefully controlled whisker motion and slowly varied the overall characteristics of the motion to provide a changing stimulus “context.” We found that stimulus–response relationships change in a particular way: the “tuning functions” that predict a neuron's response to fluctuations in whisker motion rescale according to the current stimulus distribution. The rescaling is just enough to maintain the information conveyed by the response about the stimulus. Cortical neurons adapt their responses to changes in the input statistics of a stimulus, suggesting adaptation enhances stimulus discrimination and perception.
登录
查看更多内容
影响因子：
5.4
作者：
ATTNEAVE, F
通讯作者：
ATTNEAVE, F
影响因子：
3.4
作者：
Erchova, IA;Lebedev, MA;Diamond, ME
通讯作者：
Diamond, ME
影响因子：
16.2
作者：
Adelman, TL;Bialek, W;Olberg, RM
通讯作者：
Olberg, RM
影响因子：
2.5
作者：
Fairhall, Adrienne L.;Burlingame, C. Andrew;Berry, Michael J., II
通讯作者：
Berry, Michael J., II
影响因子：
2.5
作者：
Ahissar, E;Sosnik, R;Haidarliu, S
通讯作者：
Haidarliu, S