3 years ago

Spontaneous and stimulus-induced coherent states of dynamically balanced neuronal networks.

Takashi Hayakawa, Tomoki Fukai

How the information microscopically processed in individual neurons is integrated and used for organising macroscopic behaviour of an animal is a central question in neuroscience. Coherence in dynamics over different scales has been suggested as a clue to the mechanisms underlying this integration. Balanced excitation and inhibition amplify microscopic fluctuations to a macroscopic level, and hence possibly provide a mechanism for generating coherent dynamics over the two scales. Previous theories of brain dynamics, however, were restricted to the case in which population-averaged activities were constrained to constant values, namely, the case with no macroscopic degrees of freedom. In the present study, we investigate balanced neuronal networks with a nonzero number of macroscopic degrees of freedom coupled to microscopic degrees of freedom. In these networks, amplified microscopic fluctuations serve as driving forces of macroscopic dynamics, while macroscopic dynamics determine statistics of microscopic fluctuations. We develop a novel type of mean-field theory applicable to this class of interscale interactions to which an analytical approach was previously unknown. Macroscopic irregular rhythms similar to those observed in the brain spontaneously emerge as a result of such interactions. Microscopic inputs to a small number of neurons effectively entrain the whole network through the amplification mechanism. Neuronal responses become coherent as the magnitude of balanced excitation and inhibition or that of external inputs is increased. Our mean-field theory successfully predicts the above behaviour of the model. Numerical results further suggest that the coherent dynamics can be used for selective read-out of information. In conclusion, our results show a novel form of neuronal information processing bridging different scales and advance our understanding of the brain.

Publisher URL: http://arxiv.org/abs/1711.09621

DOI: arXiv:1711.09621v2

You might also like
Discover & Discuss Important Research

Keeping up-to-date with research can feel impossible, with papers being published faster than you'll ever be able to read them. That's where Researcher comes in: we're simplifying discovery and making important discussions happen. With over 19,000 sources, including peer-reviewed journals, preprints, blogs, universities, podcasts and Live events across 10 research areas, you'll never miss what's important to you. It's like social media, but better. Oh, and we should mention - it's free.

  • Download from Google Play
  • Download from App Store
  • Download from AppInChina

Researcher displays publicly available abstracts and doesn’t host any full article content. If the content is open access, we will direct clicks from the abstracts to the publisher website and display the PDF copy on our platform. Clicks to view the full text will be directed to the publisher website, where only users with subscriptions or access through their institution are able to view the full article.