Harris K D, Hirase H, Leinekugel X, Henze D A, Buzsáki G
Center for Molecular and Behavioral Neuroscience, Rutgers, The State University of New Jersey, Newark, NJ 07102, USA.
Neuron. 2001 Oct 11;32(1):141-9. doi: 10.1016/s0896-6273(01)00447-0.
Cortical pyramidal cells fire single spikes and complex spike bursts. However, neither the conditions necessary for triggering complex spikes, nor their computational function are well understood. CA1 pyramidal cell burst activity was examined in behaving rats. The fraction of bursts was not reliably higher in place field centers, but rather in places where discharge frequency was 6-7 Hz. Burst probability was lower and bursts were shorter after recent spiking activity than after prolonged periods of silence (100 ms-1 s). Burst initiation probability and burst length were correlated with extracellular spike amplitude and with intracellular action potential rising slope. We suggest that bursts may function as "conditional synchrony detectors," signaling strong afferent synchrony after neuronal silence, and that single spikes triggered by a weak input may suppress bursts evoked by a subsequent strong input.
皮质锥体细胞会产生单个尖峰和复杂尖峰簇。然而，触发复杂尖峰所需的条件及其计算功能都尚未得到很好的理解。研究了行为大鼠中CA1锥体细胞的爆发活动。爆发的比例在位置野中心并非可靠地更高，而是在放电频率为6 - 7赫兹的位置更高。与长时间沉默（100毫秒 - 1秒）后相比，近期有尖峰活动后爆发概率更低且爆发更短。爆发起始概率和爆发长度与细胞外尖峰幅度以及细胞内动作电位上升斜率相关。我们认为，爆发可能起到“条件同步检测器”的作用，在神经元沉默后发出强传入同步的信号，并且由弱输入触发的单个尖峰可能会抑制随后由强输入诱发的爆发。
