Düzel Emrah, Bunzeck Nico, Guitart-Masip Marc, Wittmann Bianca, Schott Bjoern H, Tobler Philippe N
Institute of Cognitive Neuroscience, University College London, 17 Queen Square, London, WC13 NAR, UK.
Trends Neurosci. 2009 Jun;32(6):321-8. doi: 10.1016/j.tins.2009.02.005. Epub 2009 May 14.
Invasive recording of dopamine neurons in the substantia nigra and ventral tegmental area (SN/VTA) of behaving animals suggests a role for these neurons in reward learning and novelty processing. In humans, functional magnetic resonance imaging (fMRI) is currently the only non-invasive event-related method to measure SN/VTA activity, but it is debated to what extent fMRI enables inference about dopaminergic responses within the SN/VTA. We consider the anatomical and functional parcellation of the primate SN/VTA and find that its homogeneity suggests little variation in the regional specificity of fMRI signals for reward-related dopaminergic responses. Hence, these responses seem to be well captured by the compound fMRI signal from the SN/VTA, which seems quantitatively related to dopamine release in positron emission tomography (PET). We outline how systematic investigation of the functional parcellation of the SN/VTA in animals, new developments in fMRI analysis and combined PET-fMRI studies can narrow the gap between fMRI and dopaminergic neurotransmission.
对行为动物黑质和腹侧被盖区（SN/VTA）中的多巴胺能神经元进行侵入性记录表明，这些神经元在奖赏学习和新奇性处理中发挥作用。在人类中，功能磁共振成像（fMRI）是目前唯一用于测量SN/VTA活动的非侵入性事件相关方法，但fMRI在多大程度上能够推断SN/VTA内的多巴胺能反应仍存在争议。我们研究了灵长类动物SN/VTA的解剖和功能分区，发现其同质性表明，与奖赏相关的多巴胺能反应的fMRI信号在区域特异性上几乎没有差异。因此，这些反应似乎可以被来自SN/VTA的复合fMRI信号很好地捕捉到，而该信号在定量上似乎与正电子发射断层扫描（PET）中的多巴胺释放有关。我们概述了如何通过对动物SN/VTA功能分区的系统研究、fMRI分析的新进展以及PET-fMRI联合研究来缩小fMRI与多巴胺能神经传递之间的差距。
