Scott T R, Yaxley S, Sienkiewicz Z J, Rolls E T
J Neurophysiol. 1986 Sep;56(3):876-90. doi: 10.1152/jn.1986.56.3.876.
The responses of 165 single taste neurons in the anterior operculum of the alert cynomolgus monkey were analyzed. Chemicals were deionized water, blackcurrant juice, and the four basic taste stimuli: glucose, NaCl, HCl, and quinine HCl. Taste-evoked responses could be recorded from an opercular region that measured approximately 4.0 mm in its anteroposterior extent, 2.0 mm mediolaterally, and 3.0 mm dorsoventrally. Within this area, taste-responsive neurons were sparsely distributed such that multiunit activity was rarely encountered and neuronal isolation was readily achieved. Intensity-response functions were determined for nine cells. In each case, the lowest concentration of the dynamic response range conformed well to human electrophysiological and psychophysical thresholds for the basic taste stimuli. There was some evidence of chemotopic organization. Cells that responded best to glucose tended to be distributed toward the anterior operculum, whereas most acid-sensitive neurons were located more posteriorly. The proportion of cells responding best to NaCl peaked in the middle of the area, whereas quinine sensitivity was rather evenly distributed throughout. Opercular neurons in the monkey showed moderate breadth of sensitivity compared with taste cells of other species and at other synaptic levels. A breadth-of-tuning coefficient was calculated for each neuron. This is a metric that can range from 0.0 for a cell that responds specifically to only one of the four basic stimuli to 1.0 for one that responds equally to all four stimuli. The mean coefficient for 165 cells in the operculum was 0.67 (range = 0.12-0.99). Efforts were made to determine whether neurons could be divided into a discrete number of types, as defined by their responsiveness to the stimulus array used here. It was concluded that most taste cells may be assigned to a small number of groups, each of which is statistically independent of the others, but within which the constituent neurons are not identical. An analysis of taste quality indicated that the sweet and salty stimuli evoked patterns of activity that were significantly intercorrelated. Similarly, patterns representing HCl, quinine HCl, and water were related.
对清醒食蟹猴前鳃盖骨中165个单味觉神经元的反应进行了分析。化学物质为去离子水、黑加仑汁以及四种基本味觉刺激物：葡萄糖、氯化钠、盐酸和盐酸奎宁。在一个前后径约4.0毫米、内外侧径2.0毫米、背腹径3.0毫米的鳃盖骨区域可记录到味觉诱发反应。在该区域内，味觉反应神经元分布稀疏，因此很少遇到多单位活动，并且很容易实现神经元分离。测定了9个细胞的强度 - 反应函数。在每种情况下，动态反应范围的最低浓度与人类对基本味觉刺激的电生理和心理物理阈值非常吻合。有一些化学拓扑组织的证据。对葡萄糖反应最佳的细胞倾向于分布在前鳃盖骨，而大多数酸敏感神经元位于更靠后的位置。对氯化钠反应最佳的细胞比例在该区域中部达到峰值，而奎宁敏感性在整个区域分布较为均匀。与其他物种和其他突触水平的味觉细胞相比，猴子的鳃盖骨神经元表现出适度的敏感性广度。为每个神经元计算了调谐广度系数。这是一个指标，范围从对四种基本刺激中仅一种有特异性反应的细胞的0.0到对所有四种刺激有同等反应的细胞的1.0。鳃盖骨中165个细胞的平均系数为0.67（范围 = 0.12 - 0.99）。努力确定神经元是否可以根据它们对这里使用的刺激阵列的反应性分为离散数量的类型。得出的结论是，大多数味觉细胞可能被归为少数几组，每组在统计学上相互独立，但组内的组成神经元并不相同。味觉质量分析表明，甜味和咸味刺激诱发的活动模式显著相互关联。同样，代表盐酸、盐酸奎宁和水的模式也相互关联。
