Renjie Tong1,2 · Shaoyi Su3 · Ying Liang1,2 · Chunlin Li1,2 · Liwei Sun1,2 · Xu Zhang1,21 School of Biomedical Engineering, Capital Medical University, Beijing 100069, China
2 Beijing Key Laboratory of Fundamental Research on Biomechanics in Clinical Application, Beijing 100069, China
3 Institute of Medical Technology, Peking University Health Science Center, Beijing 100191, China
Abstract
The ability to localize sound sources rapidly allows human beings to efficiently understand the surrounding environment. Previous studies have suggested that there is an auditory “where” pathway in the cortex for processing sound locations. The neural activation in regions along this pathway encodes sound locations by opponent hemifield coding, in which each unilateral region is activated by sounds coming from the contralateral hemifield. However, it is still unclear how these regions interact with each other to form a unified representation of the auditory space. In the present study, we investigated whether functional connectivity in the auditory “where” pathway encoded sound locations during passive listening. Participants underwent functional magnetic resonance imaging while passively listening to sounds from five distinct horizontal locations (−90°, −45°, 0°, 45°, 90°). We were able to decode sound locations from the functional connectivity patterns of the “where” pathway. Furthermore, we found that such neural representation of sound locations was primarily based on the coding of sound lateralization angles to the frontal midline. In addition, whole-brain analysis indicated that functional connectivity between occipital regions and the primary auditory cortex also encoded sound locations by lateralization angles. Overall, our results reveal a lateralization-angle-based representation of sound locations encoded by functional connectivity patterns, which could add on the activation-based opponent hemifield coding to provide a more precise representation of the auditory space.
Keywords
Sound localization; Functional connectivity; Multivariate pattern analysis; Lateralization angle
