ORIGINAL ARTICLE Orienting and maintenance of spatial attention in audition and vision: multimodal and modality-specific brain activations Juha Salmi Æ Teemu Rinne Æ Alexander Degerman Æ Oili Salonen Æ Kimmo Alho Received: 19 January 2007 / Accepted: 2 July 2007 / Published online: 18 July 2007 Ó Springer-Verlag 2007 Abstract We studied orienting and maintenance of spatial attention in audition and vision. Functional magnetic reso- nance imaging (fMRI) in nine healthy subjects revealed activations in the same superior and inferior parietal, and posterior prefrontal areas in the auditory and visual orienting tasks when these tasks were compared with the corre- sponding maintenance tasks. Attention-related activations in the thalamus and cerebellum were observed during the auditory orienting and maintenance tasks and during the visual orienting task. In addition to the supratemporal audi- tory cortices, auditory orienting, and maintenance produced stronger activity than the respective visual tasks in the inferior parietal and prefrontal cortices, whereas only the occipital visual cortex and the superior parietal cortex showed stronger activity during the visual tasks than during the auditory tasks. Differences between the brain networks involved in auditory and visual spatial attention could be, for example, due to different encoding of auditory and visual spatial information or differences in stimulus-driven (bot- tom-up triggered) and voluntary (top-down controlled) attention between the auditory and visual modalities, or both. Keywords Attention Á Auditory Á Maintenance Á Orienting Á Visual Introduction Recent functional magnetic resonance imaging (fMRI) studies have compared the brain mechanisms underlying orienting and maintenance of spatial attention within the auditory and visual modalities (Shomstein and Yantis 2006; Vandenberghe et al. 2001; Yantis et al. 2002). For example, Yantis et al. (2002) used a rapid serial visual presentation task, in which subjects were presented with two letter streams, one at the left and the other at the right from the point of fixation. In this experiment, the subjects were asked to press a button in response to two digits that occurred occasionally (every 3–5 s) among the letters. One of these digits designated that the subjects were to hold their attention at the current location (maintenance of attention), and the other that attention was to be shifted to the stream of letters at the opposite side (orienting of attention). Orienting of visual attention was found to be associated with transient activation in the superior parietal lobule (SPL) bilaterally, as compared with maintenance of attention. Recently, a similar rapid serial presentation study with speech stimuli (Shomstein and Yantis 2006) revealed activations associated with orienting of auditory attention mainly in the same SPL areas. Moreover, Yantis et al. (2002) and Shomstein and Yantis (2006) found activity associated with visual and auditory orienting of attention in the middle and superior frontal gyri (MFG and SFG, respectively), that were activated by visual orienting of attention also in previous studies (e.g., Corbetta et al. 1993; Coull and Nobre 1998; Giesbrecht et al. 2003; Hopfinger et al. 2000). Consistently, clinical studies have shown that J. Salmi (&) Á T. Rinne Á A. Degerman Á K. Alho Department of Psychology, University of Helsinki, PO Box 9, Helsinki 00014, Finland e-mail: juha.salmi@helsinki.fi J. Salmi Á A. Degerman Advanced Magnetic Imaging Centre, Helsinki University of Technology, Espoo, Finland O. Salonen Helsinki Medical Imaging Center, Helsinki University Central Hospital, Helsinki, Finland 123 Brain Struct Funct (2007) 212:181–194 DOI 10.1007/s00429-007-0152-2