Dynamical model of birdsong maintenance and control

作     者：Henry D. I. Abarbanel Sachin S. Talathi Gabriel Mindlin Misha Rabinovich Leif Gibb 

作者机构：Graduate Program in Computational Neurobiology and Institute for Nonlinear Science Division of Biological Sciences University of California–San Diego La Jolla California 92093-0402 USA 

出 版 物：《Physical Review E》 (物理学评论E辑：统计、非线性和软体物理学)

年 卷 期：2004年第70卷第5期

页      面：051911-051911页

核心收录：

学科分类：07[理学] 070203[理学-原子与分子物理] 0702[理学-物理学] 

基　　金：National Institute of Neurological Disorders and Stroke, NINDS, (R01NS040110) National Institute of Neurological Disorders and Stroke, NINDS 

主　　题：Neurophysiology 

摘      要：The neuroethology of song learning, production, and maintenance in songbirds presents interesting similarities to human speech. We have developed a biophysical model of the manner in which song could be maintained in adult songbirds. This model may inform us about the human counterpart to these processes. In songbirds, signals generated in nucleus High Vocal center (HVc) follow a direct route along a premotor pathway to the robust nucleus of the archistriatum (RA) as well as an indirect route to RA through the anterior forebrain pathway (AFP): the neurons of RA are innervated from both sources. HVc expresses very sparse bursts of spikes having interspike intervals of about 2ms. The expressions of these bursts arrive at the RA with a time difference ΔT≈50±10ms between the two pathways. The observed combination of AMPA and NMDA receptors at RA projection neurons suggests that long-term potentiation and long-term depression can both be induced by spike timing plasticity through the pairing of the HVc and AFP signals. We present a dynamical model that stabilizes this synaptic plasticity through a feedback from the RA to the AFP using known connections. The stabilization occurs dynamically and is absent when the RA→AFP connection is removed. This requires a dynamical selection of ΔT. The model does this, and ΔT lies within the observed range. Our model represents an illustration of a functional consequence of activity-dependent plasticity directly connected with neuroethological observations. Within the model the parameters of the AFP, and thus the magnitude of ΔT, can also be tuned to an unstable regime. This means that destabilization might be induced by neuromodulation of the AFP.