大腦中決定序列生成的神經(jīng)機(jī)制的性質(zhì)仍是神經(jīng)科學(xué)中一個沒有得到回答的基本問題。鳴禽大腦中運(yùn)動前區(qū)中的單個神經(jīng)元能根據(jù)鳴叫聲的動態(tài)發(fā)出協(xié)調(diào)的,、在時間上精確的脈沖，因此這種鳥為這方面的研究提供了一個理想模型,。
現(xiàn)在，Long等人報告了一個技術(shù)上的“絕活”：對鳴叫的鳥的HVC神經(jīng)元進(jìn)行細(xì)胞內(nèi)記錄,，這使他們能夠驗(yàn)證關(guān)于脈沖產(chǎn)生的模型,。他們發(fā)現(xiàn)，在脈沖發(fā)生前5-10毫秒,，膜電勢迅速去極化,。這個發(fā)現(xiàn)與HVC神經(jīng)元形成突觸連接鏈的模型是一致的。（生物谷Bioon.com）
生物谷推薦英文摘要：
Nature doi:10.1038/nature09514
Support for a synaptic chain model of neuronal sequence generation
Michael A. Long,Dezhe Z. Jin& Michale S.
In songbirds, the remarkable temporal precision of song is generated by a sparse sequence of bursts in the premotor nucleus HVC. To distinguish between two possible classes of models of neural sequence generation, we carried out intracellular recordings of HVC neurons in singing zebra finches (Taeniopygia guttata). We found that the subthreshold membrane potential is characterized by a large, rapid depolarization 5–10 ms before burst onset, consistent with a synaptically connected chain of neurons in HVC. We found no evidence for the slow membrane potential modulation predicted by models in which burst timing is controlled by subthreshold dynamics. Furthermore, bursts ride on an underlying depolarization of ~10-ms duration, probably the result of a regenerative calcium spike within HVC neurons that could facilitate the propagation of activity through a chain network with high temporal precision. Our results provide insight into the fundamental mechanisms by which neural circuits can generate complex sequential behaviours.
