Oscillatory alpha-band activity (8–15 Hz) over parieto-occipital cortex in humans plays an important role in suppression of processing for inputs at to-be-ignored regions of space, with increased alpha-band power observed over cortex contralateral to locations expected to contain distractors. It is unclear if similar processes operate during deployment of spatial attention in other sensory modalities. Evidence from lesion patients suggests that parietal regions house supramodal representations of space. The parietal lobes are prominent generators of alpha-oscillations; raising the possibility that alpha is a neural signature of supramodal spatial attention. Further, when spatial attention is deployed within vision, processing of task-irrelevant auditory inputs at attended locations is also enhanced, pointing to automatic links between spatial deployments across senses. Here, we asked whether lateralized alpha-band activity is also evident in a purely auditory spatial-cueing task, and whether it had the same underlying generator configuration as in a purely visuo-spatial task. If common to both sensory-systems, this would provide strong support for “supramodal” attention theory. Alternately, alpha-band differences between auditory and visual tasks would support a sensory-specific account. Lateralized shifts in alpha-band activity were indeed observed during a purely auditory-spatial task. Crucially, there were clear differences in scalp topographies of this alpha-activity depending on the sensory system within which spatial attention was deployed. Findings suggest that parietally-generated alpha-band mechanisms are central to attentional deployments across modalities but that they are invoked in a sensory-specific manner. The data support an interactivity account, whereby a supramodal system interacts with sensory-specific control systems during deployment of spatial attention.

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Voluntary allocation of attention to environmental inputs is a crucial mechanism of healthy cognitive functioning, and is likely influenced by an observer's level of interest in a stimulus. For example, an individual passionate about soccer but bored by botany will obviously be more attentive at a soccer match than an orchid show. The influence of monetary rewards on attention has been examined, but the impact of more common motivating factors (i.e. the level of interest in the materials under observation) remains unclear, especially during development. Here, stimulus sets were designed based on survey measures of adolescent participants' level of interest in several item classes. High-density EEG was recorded during a cued spatial attention task in which stimuli of high or low interest were presented in separate blocks. Motivational impact on performance of a spatial attention task was assessed, along with event-related potential (ERP) measures of anticipatory top-down attention. As predicted, performance was improved for spatial target detection of high interest items. Further, the impact of motivation was observed in parieto-occipital processes associated with anticipatory top-down spatial attention. Anticipatory activity over these regions was also increased for high versus low interest stimuli, irrespective of the direction of spatial attention. Results also showed stronger anticipatory attentional and motivational modulations over right versus left parieto-occipital cortex. These data suggest that motivation enhances top-down attentional processes, and can independently shape activations in sensory regions in anticipation of events. They also suggest that attentional functions across hemispheres may not fully mature until late adolescence.