This paper discusses the role of event-related brain potentials (ERPs) in studying visual selective attention. ERPs provide high-resolution data on the timing of neural activity associated with perceptual and cognitive processes. Combined with blood-flow neuroimaging techniques, ERPs help localize cortical activity during visual attention. ERP modulations during spatial attention suggest a mechanism of gain control over information flow in visual pathways, starting about 80 ms after stimulus onset. Attention to nonspatial features like color, motion, or shape is associated with different ERP patterns in multiple cortical areas, beginning around 100–150 ms. These patterns are contingent upon prior spatial attention selection, consistent with early selection theories. ERPs allow analysis of the temporal microstructure of information flow in cognitive systems like attention. While blood-flow imaging methods like PET and fMRI are effective for identifying anatomical areas, they lack temporal resolution. ERPs, on the other hand, provide fine-grained temporal information about neural activation patterns. The inverse problem of ERP source localization is addressed through improved modeling techniques, including multiple dipoles or current sources. The paper highlights the contributions of ERP recordings in revealing the timing and localization of stimulus selection processes in the brain during visual attention. ERP data have been informative about the time course of visual processing and its modulation by spatial attention. The visual ERP includes components like C1, P1, and N1, with spatial attention affecting P1 and N1 amplitudes but not C1. These findings support the idea of early selection in attention, where sensory inputs are modulated before stimulus identification. The study also examines the effects of spatial attention on visual processing, showing that it influences extrastriate cortex around 80 ms post-stimulus. ERP and PET studies confirm that spatial attention modulates activity in the posterior fusiform gyrus. The P1 component is associated with extrastriate cortex, while the N1 component is linked to more anterior areas. These findings suggest that spatial attention enhances sensory information flow in visual pathways. The paper also explores the effects of nonspatial features like color or shape on ERP components, showing that attention to these features is associated with a "selection negativity" (SN) component. The SN begins around 140–180 ms post-stimulus and is linked to different cortical areas. These findings indicate that attention to nonspatial features involves distinct neural mechanisms. The study further examines the hierarchical processing of features, showing that spatial attention is "special" and plays a unique role in feature integration. ERPs and neuroimaging data reveal that attention to location affects both ventral and dorsal visual pathways. The findings support early selection theories of attention, where attentional control over perceptual processing is crucial. In conclusion, the combination of ERP and neuroimaging data provides insights into the spatial and temporal properties of neural activity during selective attention. These findings contribute to understanding the physiological basis of attention in humansThis paper discusses the role of event-related brain potentials (ERPs) in studying visual selective attention. ERPs provide high-resolution data on the timing of neural activity associated with perceptual and cognitive processes. Combined with blood-flow neuroimaging techniques, ERPs help localize cortical activity during visual attention. ERP modulations during spatial attention suggest a mechanism of gain control over information flow in visual pathways, starting about 80 ms after stimulus onset. Attention to nonspatial features like color, motion, or shape is associated with different ERP patterns in multiple cortical areas, beginning around 100–150 ms. These patterns are contingent upon prior spatial attention selection, consistent with early selection theories. ERPs allow analysis of the temporal microstructure of information flow in cognitive systems like attention. While blood-flow imaging methods like PET and fMRI are effective for identifying anatomical areas, they lack temporal resolution. ERPs, on the other hand, provide fine-grained temporal information about neural activation patterns. The inverse problem of ERP source localization is addressed through improved modeling techniques, including multiple dipoles or current sources. The paper highlights the contributions of ERP recordings in revealing the timing and localization of stimulus selection processes in the brain during visual attention. ERP data have been informative about the time course of visual processing and its modulation by spatial attention. The visual ERP includes components like C1, P1, and N1, with spatial attention affecting P1 and N1 amplitudes but not C1. These findings support the idea of early selection in attention, where sensory inputs are modulated before stimulus identification. The study also examines the effects of spatial attention on visual processing, showing that it influences extrastriate cortex around 80 ms post-stimulus. ERP and PET studies confirm that spatial attention modulates activity in the posterior fusiform gyrus. The P1 component is associated with extrastriate cortex, while the N1 component is linked to more anterior areas. These findings suggest that spatial attention enhances sensory information flow in visual pathways. The paper also explores the effects of nonspatial features like color or shape on ERP components, showing that attention to these features is associated with a "selection negativity" (SN) component. The SN begins around 140–180 ms post-stimulus and is linked to different cortical areas. These findings indicate that attention to nonspatial features involves distinct neural mechanisms. The study further examines the hierarchical processing of features, showing that spatial attention is "special" and plays a unique role in feature integration. ERPs and neuroimaging data reveal that attention to location affects both ventral and dorsal visual pathways. The findings support early selection theories of attention, where attentional control over perceptual processing is crucial. In conclusion, the combination of ERP and neuroimaging data provides insights into the spatial and temporal properties of neural activity during selective attention. These findings contribute to understanding the physiological basis of attention in humans