Helen Wills Neuroscience Institute, University of California, Berkeley, Berkeley, California 94720-3190, USA.
J Neurosci. 2012 Jul 11;32(28):9582-7. doi: 10.1523/JNEUROSCI.0909-12.2012.
Attentional processing has been associated with the dorsal attention, default mode, and frontoparietal control networks. The dorsal attention network is involved in externally focused attention whereas the default mode network is involved in internally directed attention. The frontoparietal control network has been proposed to mediate the transition between external and internal attention by coupling its activity to either the dorsal attention network or the default mode network, depending on the attentional demand. Dopamine is hypothesized to modulate attention and has been linked to the integrity of these three attention-related networks. We used PET with 6-[(18)F]fluoro-L-m-tyrosine to quantify dopamine synthesis capacity in vivo and fMRI to acquire stimulus-independent brain activity in cognitively healthy human subjects. We found that in the resting state where internal cognition dominates, dopamine enhances the coupling between the frontoparietal control network and the default mode network while reducing the coupling between the frontoparietal control network and the dorsal attention network. These results add a neurochemical perspective to the role of network interaction in modulating attention.
注意力处理与背侧注意、默认模式和额顶控制网络有关。背侧注意网络参与外部焦点注意，而默认模式网络参与内部导向注意。额顶控制网络被提议通过将其活动与背侧注意网络或默认模式网络耦合，根据注意力需求来调节外部和内部注意力之间的转换。多巴胺被假设调节注意力，并与这三个与注意力相关的网络的完整性有关。我们使用正电子发射断层扫描术（PET）与 6-[(18)F]fluoro-L-m-tyrosine 来定量活体多巴胺合成能力，并用功能磁共振成像（fMRI）在认知健康的人类受试者中获取刺激无关的大脑活动。我们发现，在内部认知占主导地位的静息状态下，多巴胺增强了额顶控制网络与默认模式网络之间的耦合，同时减少了额顶控制网络与背侧注意网络之间的耦合。这些结果为网络相互作用在调节注意力中的作用提供了神经化学视角。
