Figure 3.

Dissociation of palatability-responsive neurons into two groups based on basic response characteristics. A, An intensity plot depicting the time course of the evoked response for each of the 30 palatability-responsive LH neurons. Each row represents an individual neuron's evoked response, averaged across all five taste stimuli, and normalized to have a maximal value of 1. Neurons are sorted in order of latency to peak. For visualization purposes, evoked responses are smoothed with a 500 ms rectangular filter, although all calculations were performed on the unsmoothed responses. B, Histograms of the distributions of three basic response characteristics: (1) the percentage of the evoked response magnitude contained between 1000 and 2000 ms following taste delivery; (2) the average baseline firing rate; and (3) the latency of palatability information. C, A scatter plot of the three basic response characteristics for each of the 30 palatability-responsive neurons. Filled (20 neurons) and hollow (10 neurons) symbols denote members of two separate clusters identified via k-means analysis. Symbols with halos represent neurons with inhibitory responses. All measurements are in Z-scores.