Network identification and characterization of spatial attention in the listening brain

• Applicant: Dr. Mohsen Alavash
• Subject Area: Human Cognitive and Systems Neuroscience ; Cognitive, Systems and Behavioural Neurobiology
• Term: from 2019 to 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 426620060

How the human brain enables a listener to flexibly attend to one of multiple sounds or voices has been the topic of extensive research for nearly six decades. Functional neuroimaging suggests that, when listeners focus their attention on a particular location, cortical areas overlapping with well-known visuospatial attention networks are more active as compared to when not listening. In parallel, recent studies employing neurophysiological recordings have demonstrated robust effects of spatial attention on cortical responses to speech.However, how multi-site communication across large-scale cortical networks underlies auditory spatial attention is poorly understood. This understanding is critical to help individuals suffering from sensorineural hearing impairment and its cognitive consequences. There is now ample of evidence that hearing impaired (HI) listeners show reduced abilities in the deployment of auditory spatial attention. Today we do not know how network dynamics of the attentive listening brain are altered in the HI listeners.Naturally, flexible deployment of auditory spatial attention requires (1) a configuration of cortical networks tuned for attentive listening (i.e., condition-specific network mode), and (2) moment-to-moment reconfigurations to support switching and maintaining auditory spatial attention (i.e., fast-changing network states). Indeed, recent studies by my colleagues and me support the role of both brain network modes and network states in shaping individuals’ listening behavior. Built upon these findings, the present project proposal aims at identifying and characterizing cortical network dynamics underlying auditory spatial attention in normal hearing (NH) and HI listeners.First, using functional magnetic resonance imaging, the cortical nodes and functional connections that form a large-scale network during an auditory spatial attention task will be identified. This network identification will be based on the reconfiguration of brain networks from resting-state mode to the attentive listening mode. Next, in the second experiment, brain network states supporting the momentary deployment of spatial attention during the same auditory task will be characterized. This network characterization will be based on time-resolved functional connectivity between narrow-band neural oscillations derived from electroencephalography signals. Finally, in the third experiment, brain network states will be similarly characterized in a sample of HI listeners, and the results will be compared with those obtained from NH listeners.Accordingly, here a paradigm shift for understanding the attentive listening brain is proposed. The predictive outcomes of the current project hold implications for the design of neurorehabilitation strategies or brain-controlled hearing aids.

• DFG Programme: Research Grants