Activity in Retinotopic Visual Cortex under Focused Spatial Attention Distinguishes Empty from Distracter Locations

Activity in the retinotopic visual cortex is enhanced when the represented visual field region is covertly attended. This observation has been interpreted as a physiological correlate of the spotlight of attention (e.g., Brefczynski and DeYoe, 1999). Moreover, activity in the early visual cortex coding the immediate surround of the attended region is suppressed relatively to passive viewing thereby enhancing the contrast between attended and unattended visual field regions (Müller and Kleinschmidt, 2004). In this study we asked whether activity in the retinotopic visual cortex under focused attention is further…