Fig. 3.

A: outcome of multidimensional scaling (MDS) of neurons recorded from W (circles) and ethanol-preferring P rats (triangles) according to their responses to 0.01, 0.03, 0.1, 0.3, 0.5, and 1 M sucrose. The first 2 dimensions of 3-dimensional metric MDS applied to a matrix of Euclidean distances between neurons are shown. Open symbols denote neurons showing low sensitivity to the sucrose series (S₀ cells), and filled symbols indicate neurons with high sensitivity to sucrose (S₁ cells), as identified by k-means clustering. The number of neurons in each category is indicated. MDS and k-means gave similar partitions of cells. B: mean ± SE responses to the sucrose series by S₀ and S₁ neurons recorded from W and P rats. Key is shared with A. C: mean + SE responses to prototype stimuli (group I, Table 1) by S₀ and S₁ neurons recorded from W and P rats.