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A number of previous studies have suggested segregated networks of brain areas for top-down controlled and bottom-up triggered orienting of visual attention. However, the corresponding networks involved in auditory attention remain less studied. Our participants attended selectively to a tone stream with either a lower pitch or higher pitch in order to respond to infrequent changes in duration of attended tones. The participants were also required to shift their attention from one stream to the other when guided by a visual arrow cue. In addition to these top-down controlled cued attention shifts, infrequent task-irrelevant louder tones occurred in both streams to trigger attention in a bottom-up manner. Both cued shifts and louder tones were associated with enhanced activity in the superior temporal gyrus and sulcus, temporo-parietal junction, superior parietal lobule, inferior and middle frontal gyri, frontal eye field, supplementary motor area, and anterior cingulate gyrus. Thus, the present findings suggest that in the auditory modality, unlike in vision, top-down controlled and bottom-up triggered attention activate largely the same cortical networks. Comparison of the present results with our previous results from a similar experiment on spatial auditory attention suggests that fronto-parietal networks of attention to location or pitch overlap substantially. However, the auditory areas in the anterior superior temporal cortex might have a more important role in attention to the pitch than location of sounds. This article is part of a Special Issue entitled SI: Prediction and Attention . [ABSTRACT FROM AUTHOR]

Abstract: We used 3-T functional magnetic resonance imaging to compare the brain mechanisms underlying selective attention to sound location and pitch. In different tasks, the subjects (N = 10) attended to a designated sound location or pitch or to pictures presented on the screen. In the Attend Location conditions, the sound location varied randomly (left or right), while the pitch was kept constant (high or low). In the Attend Pitch conditions, sounds of randomly varying pitch (high or low) were presented at a constant location (left or right). Both attention to location and attention to pitch produced enhanced activity (in comparison with activation caused by the same sounds when attention was focused on the pictures) in widespread areas of the superior temporal cortex. Attention to either sound feature also activated prefrontal and inferior parietal cortical regions. These activations were stronger during attention to location than during attention to pitch. Attention to location but not to pitch produced a significant increase of activation in the premotor/supplementary motor cortices of both hemispheres and in the right prefrontal cortex, while no area showed activity specifically related to attention to pitch. The present results suggest some differences in the attentional selection of sounds on the basis of their location and pitch consistent with the suggested auditory “what” and “where” processing streams. [Copyright &y& Elsevier]