如果你发现自己需要重新阅读这段内容，那么也许它写得并不好；或者说，你也许不能集中注意力和缺乏乙酰胆碱。皮层感觉处理由选择性注意力进行重要的调制，但这种调制是怎样调控的却是一个长期未能解决的问题。在用恒河猴进行的训练让猴子探测一个闪烁的物体而忽略附近另一个闪烁的物体的实验中，向视觉皮层中施用神经传输物质乙酰胆碱，可增强猴子的表现。施用毒蕈碱（而不是尼古丁）拮抗剂，会产生相反的效应。这表明，该实验也许确定了让我们能够排除其他刺激、同时集中注意力于某一特定事项的大脑机制。（生物谷Bioon.com）
生物谷推荐原始出处：
Nature 454, 1110-1114 (28 August 2008) | doi:10.1038/nature07141
Acetylcholine contributes through muscarinic receptors to attentional modulation in V1
J. L. Herrero1,3, M. J. Roberts1,3,4, L. S. Delicato1,3,4, M. A. Gieselmann1, P. Dayan2 & A. Thiele1
Institute of Neuroscience, Newcastle University, Newcastle upon Tyne NE2 4HH, UK
Gatsby Computational Neuroscience Unit, University College London, 17 Queens Square, London WCIN 3AR, UK
These authors contributed equally to this work.
Present addresses: F. C. Donders Centre for Cognitive Neuroimaging, PO Box 9101, 6500 HB Nijmegen, The Netherlands (M.J.R.); Department of Psychology, School of Business, Law & Psychology, University of Sunderland, Sunderland SR6 0DD, UK (L.S.D.).
Attention exerts a strong influence over neuronal processing in cortical areas1, 2. It selectively increases firing rates2, 3, 4 and affects tuning properties1, 5, including changing receptive field locations and sizes3, 6. Although these effects are well studied, their cellular mechanisms are poorly understood. To study the cellular mechanisms, we combined iontophoretic pharmacological analysis of cholinergic receptors with single cell recordings in V1 while rhesus macaque monkeys (Macaca mulatta) performed a task that demanded top-down spatial attention. Attending to the receptive field of the V1 neuron under study caused an increase in firing rates. Here we show that this attentional modulation was enhanced by low doses of acetylcholine. Furthermore, applying the muscarinic antagonist scopolamine reduced attentional modulation, whereas the nicotinic antagonist mecamylamine had no systematic effect. These results demonstrate that muscarinic cholinergic mechanisms play a central part in mediating the effects of attention in V1.
