Scientists have recently discovered a novel coupling mechanism linking neuronal networks by using human intracerebral recordings. This functional coupling mechanism may serve as a communication channel between brain regions.
Neuronal oscillations are an essential piece of the working of the human brain. They control the communication between neural networks and the brain’s processing of information by pacing neuronal groups and synchronizing brain regions.
High-frequency oscillations with frequencies over 100 Hertz are known to indicate the activity of small neuronal populations. However, up to now, they have been considered to be exclusively a local phenomenon.
The study conducted at the Neuroscience Centre of the University of Helsinki and Aalto University, in collaboration with the University of Glasgow and the University of Genoa, demonstrated high-frequency oscillations over 100 Hertz synchronize across several brain regions. This critical finding reveals that high-frequency oscillations can achieve strictly-timed communication between brain regions.
High-frequency oscillations were synchronized between neuronal groups with a similar architecture of brain structures across subjects but occurring in individual frequency bands. Carrying out a visual task resulted in synchronizing high-frequency oscillations in the specific brain regions responsible for the task execution.
These observations suggest that high-frequency oscillations convey within the brain ‘information packages’ starting with one small neuronal group to another.
The discovery of high-frequency oscillations synchronized between brain regions is the first evidence of the transmission and reception of such information packages in a context broader than individual locations in the brain. The finding also helps to understand how the healthy brain processes information and how it is altered in brain diseases.
- Arnulfo, G., Wang, S.H., Myrov, V. et al. Long-range phase synchronization of high-frequency oscillations in human cortex. Nat Commun 11, 5363 (2020). DOI: 10.1038/s41467-020-18975-8