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New paper from Center for Music in the Brain in Nature Communications

By combining controlled musical sequences with MEG and MRI, MIB Associate Professor Leonardo Bonetti and colleagues reveal hierarchical processing from auditory cortices to hippocampus and cingulate gyrus, enhancing our understanding of predictive coding in memory.

Spatiotemporal brain hierarchies of auditory memory recognition and predictive coding

L. Bonetti, G. Fern√°ndez-Rubio, F. Carlomagno, M. Dietz, D. Pantazis, P. Vuust & M. L. Kringelbach 

Our brain is constantly extracting, predicting, and recognising key spatiotemporal features of the physical world in order to survive. While neural processing of visuospatial patterns has been extensively studied, the hierarchical brain mechanisms underlying conscious recognition of auditory sequences and the associated prediction errors remain elusive.

Using magnetoencephalography (MEG), we describe the brain functioning of 83 participants during recognition of previously memorised musical sequences and systematic variations. The results show feedforward connections originating from auditory cortices, and extending to the hippocampus, anterior cingulate gyrus, and medial cingulate gyrus. Simultaneously, we observe backward connections operating in the opposite direction. Throughout the sequences, the hippocampus and cingulate gyrus maintain the same hierarchical level, except for the final tone, where the cingulate gyrus assumes the top position within the hierarchy. The evoked responses of memorised sequences and variations engage the same hierarchical brain network but systematically differ in terms of temporal dynamics, strength, and polarity. Furthermore, induced-response analysis shows that alpha and beta power is stronger for the variations, while gamma power is enhanced for the memorised sequences.

This study expands on the predictive coding theory by providing quantitative evidence of hierarchical brain mechanisms during conscious memory and predictive processing of auditory sequences.

Spatiotemporal brain hierarchies of auditory memory recognition and predictive coding | Nature Communications