Previously, we and others have shown that attention can enhance visual processing in a spatially specific manner that is retinotopically mapped in the occipital cortex. However, it is difficult to appreciate the functional significance of the spatial pattern of cortical activation just by examining the brain maps. In this study, we visualize the neural representation of the “spotlight” of attention using a back-projection of attention-related brain activation onto a diagram of the visual field. In the two main experiments, we examine the topography of attentional activation in the occipital and parietal cortices. In retinotopic areas, attentional enhancement is strongest at the locations of the attended target, but also spreads to nearby locations and even weakly to restricted locations in the opposite visual field. The dispersion of attentional effects around an attended site increases with the eccentricity of the target in a manner that roughly corresponds to a constant area of spread within the cortex. When averaged across multiple observers, these patterns appear consistent with a gradient model of spatial attention. However, individual observers exhibit complex variations that are unique but reproducible. Overall, these results suggest that the topography of visual attention for each individual is composed of a common theme plus a personal variation that may reflect their own unique “attentional style.”

Our ability to manipulate and understand the use of a wide range of tools is a feature that sets humans apart from other animals. In right-handers, we previously reported that hearing hand-manipulated tool sounds preferentially activates a left hemisphere network of motor-related brain regions hypothesized to be related to handedness. Using functional magnetic resonance imaging, we compared cortical activation in strongly right-handed versus left-handed listeners categorizing tool sounds relative to animal vocalizations. Here we show that tool sounds preferentially evoke activity predominantly in the hemisphere “opposite” the dominant hand, in specific high-level motor-related and multisensory cortical regions, as determined by a separate task involving pantomiming tool-use gestures. This organization presumably reflects the idea that we typically learn the “meaning” of tool sounds in the context of using them with our dominant hand, such that the networks underlying motor imagery or action schemas may be recruited to facilitate recognition.