Rare long-range cortical connections enhance information processing

Abstract

A fundamental and unanswered question concerns the key topological features of connectivity that are critically relevant for generating the dynamics underlying efficient cortical function. A candidate feature that has recently emerged is that the connectivity of the mammalian cortex follows an exponential distance rule, which uniquely includes a small proportion of long-range high-weight anatomical connections. We investigate how these long-range connections influence whole-brain dynamics with coupled oscillators. To understand the causal function of long-range connections, we first studied these connections in simple ring structures and then in complex empirical brain architectures. A small proportion of long-range connections are sufficient for significantly improving information transmission, i.e. information cascade. Large-scale empirical neuroimaging modelling point to the immense functional benefits for information processing of a brain architecture with long-range coupling that improves the information cascade thanks to the underlying turbulent regime of brain dynamics.

The Menstrual Cycle Modulates Whole-Brain Turbulent Dynamics

“…To understand the whole-brain turbulent dynamics underlying the menstrual cycle, we applied the turbulent framework (Deco and Kringelbach, 2020 ; Deco et al, 2021b ). We investigated information processing across spacetime scales (i.e., over long and short distances in the brain) between the two main phases (i.e., follicular and luteal) of the participant's menstrual cycle.…”

“…Moreover, we computed the same empirical measures for a second dataset of the same woman undergoing hormonal treatment as a comparison between hormonal states. A complete description of the methods can be consulted in Deco and Kringelbach ( 2020 ) and Deco et al ( 2021b ).…”

“…Therefore, the novelty of the method is that it allows analyzing the brain's information processing across spacetime scales, given that the size of rotational vortices determines various scales of information transmission. This framework has been successfully applied to characterize turbulent behavior in the brain's information processing during rest and different cognitive tasks (Deco and Kringelbach, 2020 ), demonstrated that different levels of turbulent dynamics describe and differentiate between unconscious and conscious brain states (Escrichs et al, 2021 ), and showed how large-scale connections enhance the transmission of information across the whole-brain network (Deco et al, 2021b ). Therefore, the turbulent framework may advance our understanding of the effect of the two main phases of the menstrual cycle (i.e., follicular and luteal) on large-scale brain network communication.…”

“…Here, we applied the turbulent framework (Deco and Kringelbach, 2020 ; Deco et al, 2021b ; Escrichs et al, 2021 ) to the same deep-sampling datasets used in Pritschet et al ( 2020 ) and Mueller et al ( 2021 ) to investigate the brain's information processing across spacetime scales during the follicular and luteal phases of a woman's menstrual cycle. First, we applied a turbulent dynamic analysis while the participant, scanned daily over an entire menstrual cycle ( N = 30 days), was freely cycling (NaturalMenstrualCycle Study).…”