Spector Alan C, Travers Susan P
Department of Psychology and Center for Smell and Taste, University of Florida.
Behav Cogn Neurosci Rev. 2005 Sep;4(3):143-91. doi: 10.1177/1534582305280031.
The process by which the mammalian nervous system represents the features of a sapid stimulus that lead to a perception of taste quality has long been controversial. The labeled-line (sparse coding) view differs from the across-neuron pattern (ensemble) counterpoint in proposing that activity in a given class of neurons is necessary and sufficient to generate a specific taste perception. This article critically reviews molecular, electro-physiological, and behavioral findings that bear on the issue. In the peripheral gustatory system, the authors conclude that most qualities appear to be signaled by labeled lines; however, elements of both types of coding characterize signaling of sodium salts. Given the heterogeneity of neuronal tuning functions in the brain, the central coding mechanism is less clear. Both sparse coding and neuronal ensemble models remain viable possibilities. Furthermore, temporal patterns of discharge could contribute additional information. Ultimately, until specific classes of neurons can be selectively manipulated and perceptual consequences assessed, it will be difficult to go beyond mere correlation and conclusively discern the validity of these coding models.
哺乳动物神经系统表征导致味觉品质感知的美味刺激特征的过程长期以来一直存在争议。标记线（稀疏编码）观点与跨神经元模式（整体）观点不同，它提出特定类别的神经元活动对于产生特定味觉感知是必要且充分的。本文批判性地综述了与该问题相关的分子、电生理和行为学研究结果。在周围味觉系统中，作者得出结论，大多数味觉品质似乎由标记线信号传递；然而，两种编码类型的元素都参与钠盐的信号传递。鉴于大脑中神经元调谐功能的异质性，中枢编码机制尚不清楚。稀疏编码和神经元整体模型仍然都是可行的可能性。此外，放电的时间模式可能会贡献额外信息。最终，在能够选择性地操纵特定类别的神经元并评估感知结果之前，很难超越单纯的相关性并确凿地辨别这些编码模型的有效性。
