The chapter discusses the neurological syndrome of unilateral spatial neglect, which is characterized by a reduction in arousal, speed of processing, and an inability to attend to and report stimuli on the side opposite the lesion. The authors propose that this syndrome reflects deficits in the coding of saliency, control of spatial attention, and representation within an egocentric frame of reference, in conjunction with non-spatial deficits such as reorienting, target detection, and arousal/vigilance. Unlike theories linking spatial neglect to specific brain regions, the authors argue that neglect is better explained by the physiological dysfunction of distributed cortical networks. Specifically, ventral lesions in right parietal, temporal, and frontal cortex that cause neglect directly impair non-spatial functions and hypoactivate the right hemisphere, leading to abnormalities in task-evoked activity and functional connectivity of a dorsal fronto-parietal network that controls spatial attention. The anatomy and right hemisphere dominance of neglect follow from the anatomy and laterality of the ventral regions that interact with the dorsal attention network. The chapter also reviews the core spatial deficit, the egocentric bias, and the physiological correlates of the egocentric spatial bias in neglect, including topographic maps of contralateral space and inter-hemispheric control of the locus of attention. Finally, it discusses the right hemisphere lateralization of spatial neglect, suggesting that it may be due to the interaction between ventral regions damaged in neglect and the dorsal attention network.The chapter discusses the neurological syndrome of unilateral spatial neglect, which is characterized by a reduction in arousal, speed of processing, and an inability to attend to and report stimuli on the side opposite the lesion. The authors propose that this syndrome reflects deficits in the coding of saliency, control of spatial attention, and representation within an egocentric frame of reference, in conjunction with non-spatial deficits such as reorienting, target detection, and arousal/vigilance. Unlike theories linking spatial neglect to specific brain regions, the authors argue that neglect is better explained by the physiological dysfunction of distributed cortical networks. Specifically, ventral lesions in right parietal, temporal, and frontal cortex that cause neglect directly impair non-spatial functions and hypoactivate the right hemisphere, leading to abnormalities in task-evoked activity and functional connectivity of a dorsal fronto-parietal network that controls spatial attention. The anatomy and right hemisphere dominance of neglect follow from the anatomy and laterality of the ventral regions that interact with the dorsal attention network. The chapter also reviews the core spatial deficit, the egocentric bias, and the physiological correlates of the egocentric spatial bias in neglect, including topographic maps of contralateral space and inter-hemispheric control of the locus of attention. Finally, it discusses the right hemisphere lateralization of spatial neglect, suggesting that it may be due to the interaction between ventral regions damaged in neglect and the dorsal attention network.