Figure 8.

This figure demonstrates how generalized predictive coding reproduces some quantitative aspects of biased competition. The simulation (upper panel) reproduces the conditional expectations in the previous figure about valid (solid line) and invalid (dashed line) targets, when presented simultaneously. These two responses resemble those reported in Luck et al. (1997). Lower panel: peristimulus histograms (over 20 ms bins) redrawn from Luck et al. (1997), following simultaneous presentation of two (effective and ineffective) stimuli averaged over 29 V4 neurons that showed a significant attention effect. The solid line reports trials in which attention was directed to the effective stimulus (cf, responses to a valid target) and the dashed line when attention was directed to the ineffective stimulus (cf, responses to an invalid target). Note that the empirical data are non-negative spike counts, whereas the simulated activity represent firing rate deviations around baseline levels.