Poster B89, Sunday, March 25, 8:00-10:00 am, Exhibit Hall C
Low-Frequency Oscillations Mediate Cortical-Subcortical Communication During Auditory Novelty Processing
Marc Recasens1, Joachim Gross1, Peter Uhlhaas1; 1University of Glasgow
Emerging evidence supports the role of neural oscillations as a mechanism for predictive information processing across large-scale networks. However, the oscillatory mechanisms underlying auditory novelty detection and information flow between brain regions remain unclear. To address this issue, we examined the contribution of oscillatory activity at theta/alpha-bands (4-8/8-13 Hz) and assessed directed connectivity in magnetoencephalographic data while 17 human participants were presented with sound sequences containing predictable repetitions and order manipulations that elicited prediction-error responses. We characterized the spectro-temporal properties of neural generators using a minimum-norm approach and assessed directed connectivity using Granger Causality analysis. Novel sequences elicited increased theta power and phase-locking in auditory, hippocampal and prefrontal cortices, suggesting that theta-band oscillations underlie prediction-error generation in cortical-subcortical networks. Furthermore, enhanced feedforward theta-band connectivity was observed in auditory-prefrontal networks during novel sequences, while increased feedback connectivity in the alpha-band was observed between hippocampus-auditory regions during predictable sounds. Our findings highlight the involvement of hippocampal theta/alpha-band oscillations towards auditory prediction-error generation and suggest a spectral dissociation between inter-areal feedforward vs. feedback signalling, thus providing novel insights into the oscillatory mechanisms underlying auditory predictive processing.
Topic Area: PERCEPTION & ACTION: Audition