The detection of visual signals by macaque frontal eye field during masking

The neural link between a sensory signal and its behavioral report was inve stigated in macaques trained to locate an intermittently detectable visual target. Neurons in the frontal eye field, an area involved in converting th e outcome of visual processing into motor commands, responded at short late ncies to the target stimulus whether or not the monkey reported its presenc e. Neural activity immediately preceding the visual response to the mask wa s significantly greater on hits than on misses, and was significantly great er on false alarms than on correct rejections. The results show that visual signals masked by light are not filtered out at early stages of visual pro cessing; furthermore, the magnitude of early visual responses in prefrontal cortex predicts the behavioral report.