Figure 11.

CP during the sample and delay. The relationship between firing rates and the monkeys' choices was evaluated with ROC analysis on trials when the sample contained no net direction (360° range). A, Average CP for 170 MT neurons during the sample and memory delay. A positive significant CP (p < 0.001, t test) was seen during the sample response, correlating higher firing rates with choices that indicated the sample as having been preferred. No such correlation was present from the end of the sample response through the entire memory delay. Light gray curves indicate ±1 SEM. B, Distributions showing CPs of individual neurons during the sample and three representative epochs of the delay. Significant individual CPs (95% confidence, permutation test) are indicated by black bars. C, Average CP for 40 PFC neurons during the sample and memory delay. No significant correlation between firing rates and choices (p > 0.05, t test) was seen at any time during the sample or memory delay. D, Distributions showing CPs of individual PFC neurons during the sample and three representative epochs of the delay. Details are as in B.