Cortical remodelling induced by activity of ventral tegmental dopamine neurons
Cortical remodelling induced by activity of ventral tegmental dopamine neurons
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DOI：
10.1038/35083586
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发表时间：
2001-07-05
期刊：
影响因子：
64.8
通讯作者：
Merzenich, MM
中科院分区：
文献类型：
--
作者：
Bao, SW;Chan, WT;Merzenich, MM
大脑皮层中感觉刺激的表征可以根据刺激(1，2)的行为重要性进行渐进式重塑。大脑皮质从腹侧被盖区(VTA)的多巴胺神经元接受广泛的投射(3-5)，这些投射被新的刺激或不可预测的奖励(6，7)激活，并被认为为这种与学习相关的皮质重组提供了强化信号(8)。在初级听觉皮质(AI)，在听觉学习期间观察到多巴胺的释放，这一过程重塑了声音频率表示(9，10)。此外，多巴胺调节长时程增强(11，12)，这是导致可塑性的假定细胞机制(13)。在这里，我们表明，刺激VTA与特定音调的听觉刺激一起增加了人工智能中对该声音刺激的神经反应的皮质面积和选择性。相反，附近声音频率的人工智能表示被选择性地降低。对配对音调的强烈、尖锐的反应也出现在第二个皮质区域，而同样的刺激在幼稚动物的第二个皮质区域只引起较差的或非选择性的反应。此外，我们还发现在人工智能和这个次级听觉皮质区域之间出现了神经元放电的强烈长程一致性。
Representations of sensory stimuli in the cerebral cortex can undergo progressive remodelling according to the behavioural importance of the stimuli(1,2). The cortex receives widespread projections from dopamine neurons in the ventral tegmental area (VTA)(3-5), which are activated by new stimuli or unpredicted rewards(6,7), and are believed to provide a reinforcement signal for such learning-related cortical reorganization(8). In the primary auditory cortex (AI) dopamine release has been observed during auditory learning that remodels the sound-frequency representations(9,10). Furthermore, dopamine modulates longterm potentiation(11,12), a putative cellular mechanism underlying plasticity(13). Here we show that stimulating the VTA together with an auditory stimulus of a particular tone increases the cortical area and selectivity of the neural responses to that sound stimulus in AI. Conversely, the AI representations of nearby sound frequencies are selectively decreased. Strong, sharply tuned responses to the paired tones also emerge in a second cortical area, whereas the same stimuli evoke only poor or non-selective responses in this second cortical field in naive animals. In addition, we found that strong long-range coherence of neuronal discharge emerges between AI and this secondary auditory cortical area.