Université de Bordeaux, Institut des Maladies Neurodégénératives, UMR 5293, F-33000 Bordeaux, France.
Neuron. 2012 Sep 6;75(5):889-903. doi: 10.1016/j.neuron.2012.06.036.
Oscillatory patterns of activity in various frequency ranges are ubiquitously expressed in cortical circuits. While recent studies in humans emphasized rhythmic modulations of neuronal oscillations ("second-order" rhythms), their potential involvement in information coding remains an open question. Here, we show that a rhythmic (~0.7 Hz) modulation of hippocampal theta power, unraveled by second-order spectral analysis, supports encoding of spatial and behavioral information. The phase preference of neuronal discharge within this slow rhythm significantly increases the amount of information carried by action potentials in various motor/cognitive behaviors by (1) distinguishing between the spikes fired within versus outside the place field of hippocampal place cells, (2) disambiguating place firing of neurons having multiple place fields, and (3) predicting between alternative future spatial trajectories. This finding demonstrates the relevance of second-order spectral components of brain rhythms for decoding neuronal information.
在皮质电路中，各种频率范围内的活动波动模式普遍存在。虽然最近在人类中的研究强调了神经元波动的节奏调制（“二阶”节律），但其在信息编码中的潜在作用仍是一个悬而未决的问题。在这里，我们表明，通过二阶频谱分析揭示的海马theta 功率的节律性（~0.7 Hz）调制支持空间和行为信息的编码。在这个缓慢的节律中，神经元放电的相位偏好通过以下方式显著增加了各种运动/认知行为中动作电位携带的信息量：（1）区分海马体位置细胞的位置场内外的放电尖峰，（2）分辨具有多个位置场的神经元的位置放电，以及（3）预测替代的未来空间轨迹。这一发现证明了脑节律的二阶频谱成分对于解码神经元信息的相关性。
