Hippocampal and cortical communication around micro-arousals in slow-wave sleep

Abstract

Sleep plays a crucial role in the regulation of body homeostasis and rhythmicity in mammals. Recently, a specific component of the sleep structure has been proposed as part of its homeostatic mechanism, named micro-arousal. Here, we studied the unique progression of the dynamic behavior of cortical and hippocampal local field potentials (LFPs) during slow-wave sleep-related to motor-bursts (micro-arousals) in mice. Our main results comprised: (i) an abrupt drop in hippocampal LFP amplitude preceding micro-arousals which persisted until the end of motor-bursts (we defined as t interval, around 4s) and a similar, but delayed amplitude reduction in cortical (S1/M1) LFP activity occurring at micro-arousal onset; (ii) two abrupt frequency jumps in hippocampal LFP activity: from Theta (6–12 Hz) to Delta (2–4 Hz), also t seconds before the micro-arousal onset, and followed by another frequency jump from Delta to Theta range (5–7 Hz), now occurring at micro-arousal onset; (iii) a pattern of cortico-hippocampal frequency communication precedes micro-arousals: the analysis between hippocampal and cortical LFP fluctuations reveal high coherence during τ interval in a broader frequency band (2–12 Hz), while at a lower frequency band (0.5–2 Hz) the coherence reaches its maximum after the onset of micro-arousals. In conclusion, these novel findings indicate that oscillatory dynamics pattern of cortical and hippocampal LFPs preceding micro-arousals could be part of the regulatory processes in sleep architecture.

The New Field of Network Physiology: Building the Human Physiolome

“…The network physiology perspective has redefined physiologic states from point of view of dynamic networks of organ interactions. Utilizing this new perspective, recent studies have focused on 1) investigating brain-brain network interactions across distinct brain rhythms and locations, and their relation to new aspects of neural plasticity in response to changes in physiologic state; 2) characterizing dynamical features of brain-organ communications as a new signature of neuroautonomic control; 3) establishing basic principles underlying coordinated organ-organ communications, and 4) constructing first dynamic maps of physiological systems and organ interactions across distinct physiologic states (Bashan et al, 2012;Bartsch et al, 2012;Ivanov and Bartsch, 2014;Liu et al, 2015a;Liu et al, 2015b;Bartsch et al, 2015;Lin et al, 2016;Ivanov et al, 2017Ivanov et al, , 2021bDvir et al, 2018;dos Santos Lima et al, 2019;Lin et al, 2020;Rizzo et al, 2020;Ivanov et al, 2021a;Balagué et al, 2020). Pioneering investigations have made first insights into structural and functional connectivity of physiologic networks underlying individual organ systems and their sub-systems (Tass et al, 1998;Bullmore and Sporns, 2009;Gallos et al, 2012;Liu et al, 2015a;Neufang and Akhrif, 2020;Cohen et al, 2021;Cook et al, 2021), and how global behaviors at the organism level, different physiologic states and functions arise out of networked interactions among organ systems to generate health or disease (Bashan et al, 2012;Ivanov and Bartsch, 2014;Karavaev et al, 2020;Pernice et al, 2020;Tecchio et al, 2020;Wood et al, 2020;Zavala et al, 2020;Angelova et al, 2021;…”

Low-cost and versatile electrodes for extracellular chronic recordings in rodents

“…Considering the use of larger animals, like rats, the characteristics mentioned above make it possible to upscale the number of electrode arrays implanted ( Figure 1 D). Besides that, these electrodes were used for long recording sections (up to 12 h) without disturbing the sleep wake cycle of the animal ( dos Santos Lima et al., 2019 ; França et al., 2015 ).…”

Low-cost and versatile electrodes for extracellular chronic recordings in rodents

“…Due to the light weight of the electrodes, even with multiple electrodes implanted in different brain regions, these electrode arrays do not interfere with animal welfare or behavioral performance (França et al, 2014). Besides that, these electrodes were used for long recording sections (up to 12 hours) without disturbing the sleep wake cycle of the animal (dos Santos Lima et al, 2019;França et al, 2015).…”