Neural signatures of intersensensory attention: investigating the role of neural synchrony and functional network properties

• Applicant: Professor Dr. Daniel Senkowski
• Subject Area: General, Cognitive and Mathematical Psychology ; Human Cognitive and Systems Neuroscience
• Term: from 2014 to 2017
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 261401459

Picture yourself trying to spot a friend in the crowd of runners at a marathon. You are able to ignore the cheering of the spectators while simultaneously focusing on the visual impressions of the runners. Intersensory attention describes our ability to attend to stimuli in a selected modality while ignoring input from other modalities. Thus far, studies on intersensory attention have mainly focused on the processing of actually presented stimuli. However, top-down orienting of intersensory attention can also bias the brain states prior to stimulus presentation. Functional neuroimaging studies suggested that intersensory attention can cause parallel and selective enhancements and suppressions of neural activity in different cortical areas. In addition, electrophysiological studies indicated that neural synchrony, as reflected in oscillatory activity, could be an important mechanism therein. To date, however, only a few studies have examined the role of neural oscillations for intersensory attention. Moreover, no study has investigated the functional significance of selected brain areas, such as primary sensory cortices, for intersensory attention. We will address these issues in three experiments using electroencephalography (EEG) and transcranial magnetic stimulation (TMS). All three experiments are comprised of a cue-target paradigm, in which an auditory cue indicates to which sensory modality (visual or tactile) participants should direct their attention prior to the appearance of a visual-tactile target stimulus. We will use state-of-the-art source analysis methods to investigate effects on neural oscillations recorded via EEG when stimuli are presented with variable (Experiment 1) or fixed (Experiment 2) inter-stimulus intervals (ISI). Notably, an orienting of temporal attention is only useful in Experiment 2. Experiments 1 and 2 will reveal novel information about to which degree enhanced processing in the attended modality, and suppression of processing in the unattended modality, relate to intersensory attention and temporal orienting. In Experiment 3, we will apply single-pulse TMS to selected cortical areas, such as primary sensory cortices, to interrupt local cortical processing during the cue-target interval. We will use the paradigms of Experiments 1 and 2, which will allow us to draw conclusions about the functional significance of these regions for intersensory attention. Taken together, the proposed project will further our understanding of the neurophysiological mechanisms underlying intersensory attention and their relationships to temporal orienting.

• DFG Programme: Research Grants
• Participating Person: Professor Dr. Julian Maximilian Felix Keil