Small Dana M, Gregory Michael D, Mak Y Erica, Gitelman Darren, Mesulam M Marsel, Parrish Todd
Cognitive Neurology and Alzheimer's Disease Center, Northwestern University Feinberg Medical School, 320 East Superior Street, Chicago, IL 60611, USA.
Neuron. 2003 Aug 14;39(4):701-11. doi: 10.1016/s0896-6273(03)00467-7.
We used a 2 x 2 factorial design to dissociate regions responding to taste intensity and taste affective valence. Two intensities each of a pleasant and unpleasant taste were presented to subjects during event-related fMRI scanning. The cerebellum, pons, middle insula, and amygdala responded to intensity irrespective of valence. In contrast, valence-specific responses were observed in anterior insula/operculum extending into the orbitofrontal cortex (OFC). The right caudolateral OFC responded preferentially to pleasant compared to unpleasant taste, irrespective of intensity, and the left dorsal anterior insula/operculuar region responded preferentially to unpleasant compared to pleasant tastes equated for intensity. Responses best characterized as an interaction between intensity and pleasantness were also observed in several limbic regions. These findings demonstrate a functional segregation within the human gustatory system. They also show that amygdala activity may be driven by stimulus intensity irrespective of valence, casting doubt upon the notion that the amygdala responds preferentially to negative stimuli.
我们采用2×2析因设计来区分对味觉强度和味觉情感效价产生反应的区域。在事件相关功能磁共振成像扫描期间，向受试者呈现了两种强度的愉悦味觉和两种强度的不愉悦味觉。小脑、脑桥、岛叶中部和杏仁核对强度产生反应，而与效价无关。相比之下，在延伸至眶额皮质（OFC）的前岛叶/岛盖区域观察到了效价特异性反应。右侧尾外侧眶额皮质无论强度如何，对愉悦味觉的反应均优先于不愉悦味觉，而左侧背侧前岛叶/岛盖区域对强度相等的不愉悦味觉的反应优先于愉悦味觉。在几个边缘区域也观察到了最能表征为强度与愉悦度之间相互作用的反应。这些发现证明了人类味觉系统内的功能分离。它们还表明，杏仁核活动可能由刺激强度驱动，而与效价无关，这对杏仁核优先对负面刺激做出反应的观点提出了质疑。
