Laboratory of Brain and Cognition, National Institute of Mental Health, Bethesda, MD 20892
Laboratory of Brain and Cognition, National Institute of Mental Health, Bethesda, MD 20892.
Proc Natl Acad Sci U S A. 2021 Jan 12;118(2). doi: 10.1073/pnas.2010932118.
Previous studies have shown that the conceptual representation of food involves brain regions associated with taste perception. The specificity of this response, however, is unknown. Does viewing pictures of food produce a general, nonspecific response in taste-sensitive regions of the brain? Or is the response specific for how a particular food tastes? Building on recent findings that specific tastes can be decoded from taste-sensitive regions of insular cortex, we asked whether viewing pictures of foods associated with a specific taste (e.g., sweet, salty, and sour) can also be decoded from these same regions, and if so, are the patterns of neural activity elicited by the pictures and their associated tastes similar? Using ultrahigh-resolution functional magnetic resonance imaging at high magnetic field strength (7-Tesla), we were able to decode specific tastes delivered during scanning, as well as the specific taste category associated with food pictures within the dorsal mid-insula, a primary taste responsive region of brain. Thus, merely viewing food pictures triggers an automatic retrieval of specific taste quality information associated with the depicted foods, within gustatory cortex. However, the patterns of activity elicited by pictures and their associated tastes were unrelated, thus suggesting a clear neural distinction between inferred and directly experienced sensory events. These data show how higher-order inferences derived from stimuli in one modality (i.e., vision) can be represented in brain regions typically thought to represent only low-level information about a different modality (i.e., taste).
先前的研究表明，食物的概念表示涉及与味觉感知相关的大脑区域。然而，这种反应的特异性尚不清楚。观看食物的图片是否会在大脑中味觉敏感区域产生一般的、非特异性的反应？或者反应是针对特定食物的味道特异性的？基于最近的发现，即特定的味道可以从岛叶皮质的味觉敏感区域解码出来，我们想知道观看与特定味道（例如甜、咸和酸）相关的食物图片是否也可以从这些相同的区域解码出来，如果可以，那么图片及其相关味道引起的神经活动模式是否相似？我们使用超高分辨率功能磁共振成像在高磁场强度（7 特斯拉）下，能够在扫描过程中解码特定的味道，以及在背侧中脑岛的味觉敏感区域内与食物图片相关的特定味觉类别。因此，仅仅观看食物图片就会在味觉皮层中自动检索与所描绘食物相关的特定味觉质量信息。然而，图片和它们相关的味道所引起的活动模式是无关的，因此表明在推断和直接体验感官事件之间存在明显的神经区分。这些数据表明，来自一种感觉模式（即视觉）的刺激所产生的更高阶推断如何可以在通常被认为仅代表不同感觉模式（即味觉）的低水平信息的大脑区域中得到表示。
