Modulation of the earliest visual evoked potential by attention: now you see it, now you don't

Baumgartner and colleagues (this issue) report a replication of an ERP study by Kelly, Gomez-Ramirez, and Foxe (2008). Unlike the original authors, they failed to observe a significant modulation of the C1 by visuo-spatial attention. They conclude that initial afferent processing in V1 is impermeable to visuo-spatial attention. Although their study, like any replication effort, is valuable and important, there are some uncertainties at the methodological and statistical levels suggesting that the absence of evidence is not evidence of absence in the present case.