Somers D, Kopell N
Department of Cognitive and Neural Systems, Boston University, MA 02215.
Biol Cybern. 1993;68(5):393-407. doi: 10.1007/BF00198772.
Synchronization properties of locally coupled neural oscillators were investigated analytically and by computer simulation. When coupled in a manner that mimics excitatory chemical synapses, oscillators having more than one time scale (relaxation oscillators) are shown to approach synchrony using mechanisms very different from that of oscillators with a more sinusoidal waveform. The relaxation oscillators make critical use of fast modulations of their thresholds, leading to a rate of synchronization relatively independent of coupling strength within some basin of attraction; this rate is faster for oscillators that have conductance-based features than for neural caricatures such as the FitzHugh-Nagumo equations that lack such features. Computer simulations of one-dimensional arrays show that oscillators in the relaxation regime synchronize much more rapidly than oscillators with the same equations whose parameters have been modulated to yield a more sinusoidal waveform. We present a heuristic explanation of this effect based on properties of the coupling mechanisms that can affect the way the synchronization scales with array length. These results suggest that the emergent synchronization behavior of oscillating neural networks can be dramatically influenced by the intrinsic properties of the network components. Possible implications for perceptual feature binding and attention are discussed.
通过分析和计算机模拟研究了局部耦合神经振荡器的同步特性。当以模拟兴奋性化学突触的方式耦合时，具有多个时间尺度的振荡器（弛豫振荡器）被证明使用与具有更正弦波形的振荡器非常不同的机制来接近同步。弛豫振荡器关键地利用其阈值的快速调制，导致在某些吸引域内同步速率相对独立于耦合强度；具有基于电导特征的振荡器的同步速率比缺乏此类特征的神经模型（如FitzHugh-Nagumo方程）更快。一维阵列的计算机模拟表明，弛豫状态下的振荡器比具有相同方程但其参数已被调制以产生更正弦波形的振荡器同步得更快。我们基于耦合机制的特性对这种效应提出了一种启发式解释，这种耦合机制特性会影响同步随阵列长度缩放的方式。这些结果表明，振荡神经网络的涌现同步行为可能会受到网络组件固有特性的显著影响。文中还讨论了对感知特征绑定和注意力的可能影响。
