Frequency-selective coding of translation and tilt in macaque cerebellar nodulus and uvula.
Frequency-selective coding of translation and tilt in macaque cerebellar nodulus and uvula.
复制标题
DOI：
10.1523/jneurosci.2232-08.2008
复制
发表时间：
2008-10-01
期刊：
影响因子：
--
通讯作者：
Angelaki DE
中科院分区：
文献类型：
--
作者：
Yakusheva T;Blazquez PM;Angelaki DE
空间方向的关键取决于大脑的能力，分离线性加速度信号所产生的耳石传入到估计的自我运动和方向相对于重力。在缺乏视觉信息的情况下，这种能力在低频下会恶化。小脑结节/悬雍垂（NU）已被证明参与这一计算，但其确切的作用仍不清楚。在这里，我们表明，NU简单穗（SS）的反应也表现出频率依赖的选择性自我运动（平移）和空间方向（tit）。在0.5 Hz时，浦肯野细胞编码三维（3D）平移，并且仅在俯仰和翻滚倾斜期间进行微弱调制（0.4 ± 0.05 spikes/s/°/s）。但是，在较低频率下，这种选择性地通过倾斜进行信号转换的能力受到损害，使得在0.05 Hz下，倾斜响应增益平均为2.0 ± 0.3尖峰/s/°/s。我们表明，这种频率依赖性是由于耳石驱动的SS响应的不完全抵消倾斜期间的通道驱动的信号编码角位置的灵敏度为3.9 ± 0.3尖峰/s/°。这种不完全抵消是因为耳石驱动的SS响应也被部分积分，从而编码线速度和加速度的组合。这些结果与NU SS调制代表在行为中看到的类似频率依赖性的内部神经表示的概念一致。
Spatial orientation depends critically on the brain’s ability to segregate linear acceleration signals arising from otolith afferents into estimates of self-motion and orientation relative to gravity. In the absence of visual information, this ability is known to deteriorate at low frequencies. The cerebellar nodulus/uvula (NU) has been shown to participate in this computation, although its exact role remains unclear. Here we show that NU simple spike (SS) responses also exhibit a frequency dependent selectivity to self-motion (translation) and spatial orientation (tit). At 0.5 Hz, Purkinje cells encode three-dimensional (3D) translation and only weakly modulate during pitch and roll tilt (0.4 ± 0.05 spikes/s/°/s). But this ability to selectively signal translation over tilt is compromised at lower frequencies, such that at 0.05 Hz tilt response gains average 2.0 ± 0.3 spikes/s/°/s. We show that such frequency-dependent properties are due to an incomplete cancellation of otolith-driven SS responses during tilt by a canal-driven signal coding angular position with a sensitivity of 3.9 ± 0.3 spikes/s/°. This incomplete cancellation is brought about because otolith-driven SS responses are also partially integrated, thus encoding combinations of linear velocity and acceleration. These results are consistent with the notion that NU SS modulation represents an internal neural representation of similar frequency dependencies seen in behavior.