 The traditional late selection theory is right in taking it that inattention can lead to properties being encoded without our awareness, rather than not being encoded at all, but that theory is also committed to the claim that attention’s only effects are in determining what gets remembered and experienced, so that the direction of attention has no effects on the initial perceptual processing to which stimuli are subjected. These latter claims we now know to be false. An important experiment by O’Connor et al. used fMRI to compare neural activity in participants who, in various task conditions, were presented with high and low contrast checkerboard patterns in one or other half of their visual field (O’Connor et al. 2002). In some conditions these participants had to perform a task involving these checkerboard patterns. In other conditions the patterns were irrelevant to the task that the participants were performing (and in a third condition no pattern was presented, but the participants were attending to the screen in anticipation of a pattern that was about to be presented). The results of these comparisons reveal that even in the first parts of the neural circuitry through which information from the retina passes, on its way to the visual cortex—even, that is, in the Lateral Geniculate Nuclei—there is a difference in the baserate of neural activity, and a difference in the response that stimuli elicit, depending on what the participant is attending to. These findings indicate that attention’s effects are not limited to cortical loci that are upstream from a late process of attentional selection. They therefore refute any version of the late-selection theory according to which the selectivity of attention is entirely a ‘late process’, occurring only after initial perceptual encoding is complete.