Does spatial attention modulate the C1 component? The jury continues to deliberate.

The thoughful comments on our study (Baumgartner et al., this issue) that failed to replicate the C1 attention effect reported by a previous study roughly fall into three broad categories. First, the commentators identified specific differences between the two studies that may have contributed to the discrepant results. Second, they highlighted some of the theoretical and methodological problems that are encountered when trying to demonstrate attention effects on the initial evoked response in primary visual cortex. Third, they offered a number of proposals for optimizing experimental designs and analysis methods that may increase the likelihood of observing attention-related modulations of the C1. We consider each of these topics in turn.