Fig. 7.

Physiological data for populations of V1 neurons collected from 2 monkeys (monkey 1, left; monkey 2, right) while the animals performed the same detection task shown in Fig. 2A. A and B: comparisons of the corrected and uncorrected DPs calculated for individual neurons with the corresponding marginal distributions. Only neurons for which at least 10 hit trials and 10 miss trials were available for the calculation of DPs were included, and the mean numbers of trials for a given neuron were 299 for uncorrected and 166 for corrected DPs. See text for details of the methods used to calculate the corrected and uncorrected DPs. C and D: average normalized responses of individual neurons shown in A and B plotted as a function of target position in the stimulus sequence within a trial. The responses for the first 4 of 6 possible target positions are shown because of the scarcity of trials for the last 2 target positions. To obtain normalized responses for a neuron, the mean response within each target position collected at a given target direction was divided by the mean response for that target direction and then averaged across different target directions. E and F: performance as a function of target position. Performance is the average of those from individual sessions in which the neurons in A and B were recorded. For a given session, the proportion correct at a given target position was the number of hit trials divided by the sum of the hit and miss trials, pooled across different target directions that contributed to the calculation of DP of the neuron. Error bars in C–F indicate SE.