Sensory-Evoked and Spontaneous Gamma and Spindle Bursts in Neonatal Rat Motor Cortex
Sensory-Evoked and Spontaneous Gamma and Spindle Bursts in Neonatal Rat Motor Cortex
复制标题
DOI：
10.1523/jneurosci.4539-13.2014
复制
发表时间：
2014-08-13
影响因子：
5.3
通讯作者：
Luhmann, Heiko J.
中科院分区：
文献类型：
--
作者：
An, Shuming;Kilb, Werner;Luhmann, Heiko J.
起源于皮层下区域的自发神经元活动驱动早期自发运动活动，这是发育中的感觉运动系统的标志。然而，初级运动皮层（M1）在这些早期运动中的神经活动模式和作用仍然未知。结合电压敏感染料成像（VSDI），同时在出生后第3天（P3）-P5大鼠的初级躯体感觉皮层（S1）和M1在体内的细胞外多电极记录，我们观察到，触觉前爪刺激引起的S1和伽马和M1的纺锤波爆发。M1中约40%的自发伽马和纺锤体爆发由早期运动活动驱动，而M1爆发的23.7%触发前爪运动。大约35%的M1爆发与运动无关，这些爆发的尖峰明显较少，爆发持续时间较短。在M1模仿生理相关的40 Hz γ或10 Hz的纺锤波爆发活动的V层神经元的局灶性电刺激可靠地引起前爪运动。我们的结论是，M1已经参与了体感信息处理在早期发展。M1主要由触觉刺激激活，触觉刺激由先前的自发运动触发，这些自发运动通过S1到达M1。只有一小部分M1活动瞬变直接触发运动反应。我们认为，自发发生的和感觉诱发的伽玛和纺锤体爆发在M1有助于成熟的皮质脊髓和感觉运动网络所需的完善的感觉运动协调。
Self-generated neuronal activity originating from subcortical regions drives early spontaneous motor activity, which is a hallmark of the developing sensorimotor system. However, the neural activity patterns and role of primary motor cortex (M1) in these early movements are still unknown. Combining voltage-sensitive dye imaging (VSDI) with simultaneous extracellular multielectrode recordings in postnatal day 3 (P3)-P5 rat primary somatosensory cortex (S1) and M1 in vivo, we observed that tactile forepaw stimulation induced spindle bursts in S1 and gamma and spindle bursts in M1. Approximately 40% of the spontaneous gamma and spindle bursts in M1 were driven by early motor activity, whereas 23.7% of the M1 bursts triggered forepaw movements. Approximately 35% of the M1 bursts were uncorrelated to movements and these bursts had significantly fewer spikes and shorter burst duration. Focal electrical stimulation of layer V neurons in M1 mimicking physiologically relevant 40 Hz gamma or 10 Hz spindle burst activity reliably elicited forepaw movements. We conclude that M1 is already involved in somatosensory information processing during early development. M1 is mainly activated by tactile stimuli triggered by preceding spontaneous movements, which reach M1 via S1. Only a fraction of M1 activity transients trigger motor responses directly. We suggest that both spontaneously occurring and sensory-evoked gamma and spindle bursts in M1 contribute to the maturation of corticospinal and sensorimotor networks required for the refinement of sensorimotor coordination.