Friedman-Hill S, Maldonado P E, Gray C M
The Center for Neuroscience, University of California, 1544 Newton Ct, Davis, CA 95616, USA.
Cereb Cortex. 2000 Nov;10(11):1105-16. doi: 10.1093/cercor/10.11.1105.
Using single and multiunit recordings in the striate cortex of alert macaque monkeys, we find that gamma-band (20-70 Hz) oscillations in neuronal firing are a prominent feature of V1 neuronal activity. The properties of this rhythmic activity are very similar to those previously observed in the cat. Gamma-band activity is strongly dependent on visual stimulation, largely absent during spontaneous activity and, under the conditions of our experiment, not time-locked to the vertical refresh of the computer monitor (80 Hz) used to present the stimuli. In our sample, 61% of multiunit activity (MUA) and 46% of single-unit activity (SUA) was significantly oscillatory, with mean frequencies of 48+/-9 and 42+/-13 Hz, respectively. Gamma-band activity was most likely to occur when cells were activated by their optimal stimuli, but still occurred, although less often and with lower amplitude, in response to nonoptimal stimuli. The frequency of gamma-band activity also reflected stimulus properties, with drifting gratings evoking higher-frequency oscillations than stationary gratings. As in the cat, the spike trains of single cells showing gamma-band oscillations often displayed a pattern of repetitive burst firing, with intraburst firing rates of 300-800 Hz. The overall similarity of rhythmic neuronal activity in the primary visual cortex of cats and monkeys suggests that the phenomenon is not species-specific. The stimulus-dependence of the rhythmic activity is consistent with a functional role in visual perception.
通过在警觉的猕猴纹状皮层中进行单神经元和多神经元记录，我们发现神经元放电中的γ波段（20 - 70赫兹）振荡是V1神经元活动的一个显著特征。这种节律性活动的特性与先前在猫身上观察到的非常相似。γ波段活动强烈依赖于视觉刺激，在自发活动期间基本不存在，并且在我们的实验条件下，与用于呈现刺激的计算机显示器的垂直刷新率（80赫兹）没有时间锁定关系。在我们的样本中，61%的多神经元活动（MUA）和46%的单神经元活动（SUA）有显著的振荡，平均频率分别为48±9赫兹和42±13赫兹。当细胞被其最佳刺激激活时，γ波段活动最有可能出现，但对非最佳刺激也会出现，尽管频率较低且幅度较小。γ波段活动的频率也反映了刺激特性，漂移光栅比静止光栅引发更高频率的振荡。与猫一样，显示γ波段振荡的单个细胞的脉冲序列通常呈现出重复爆发式放电模式，爆发内放电率为300 - 800赫兹。猫和猴的初级视觉皮层中节律性神经元活动的总体相似性表明，这种现象不是物种特异性的。节律性活动对刺激的依赖性与在视觉感知中的功能作用一致。
