1. Shaping the Default Activity Pattern of the Cortical Network
Maria V. Sanchez-Vives, Marcello Massimini, Maurizio Mattia 
Neuron 
Volume 94, Issue 5, Pages (June 2017)
DOI: /j.neuron
Copyright © 2017 Elsevier Inc. Terms and Conditions

2. Figure 1
Shaping Slow Oscillations in Experimental and Pathological Conditions
(A) SO recorded with EEG from frontal regions under propofol anesthesia (top trace) and during spontaneous sleep in humans (middle trace). Butterfly plots of mastoid-referenced high-density- (hd-)EEG traces during anesthesia (right panel, bottom) and amplitude-matched slow waves (left panel, bottom). From Murphy et al. (2011).
(B) SO recorded in vitro intracellularly (top) and extracellularly (multiunit activity, MUA; bottom) from ferret visual cortex.
(C) Average firing rate of Up states (shadow, SEM) during 6 increasing concentrations of bicuculline methiodide (GABAA blocker). From Sanchez-Vives et al. (2010).
(D) Top: raster plots of firing rates of 50 Up states centered around the Up state onsets in different temperature intervals (left, 32°C–32.5°C; center, 36.5°C–37°C; right, 41°C–41.5°C). Bottom: corresponding average relative firing rates (shade, SE). From Reig et al. (2010).
(E) Top: coefficient of variation (CV) of the Up/Down cycle duration versus relative extracellular potassium concentration [K+]o. Bottom: effect of varying [K+]o on the standard deviation of the log(MUA) during the Down states. From Sancristobal et al. (2016).
(F) Top: raster plots of the firing rates of 100 Up states in wild-type (left) and TgDyrk1A (right) mice. Bottom: decrease in gamma frequencies in prefrontal cortex of TgDyrk1A mice. Bottom left: relative (Up/Down) power spectrum density (shade, SEM); bottom right: first and third quartiles with the median relative power in different frequency ranges (center black line). ∗p < 0.05, Mann-Whitney U test. From Ruiz-Mejias et al. (2016).
Neuron  , DOI: ( /j.neuron )
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3. Figure 2
Theoretical Ground Underpinning the Default-Activity Mode Hypothesis
(A) Up and Down SO from slices (black) and reconstructed activity-dependent adaptation level (red). Colored arrows, different phases of SO cycle as in (B).
(B) Phase-plane of a mean-field relaxation oscillator modeling SO. Left: “nullclines” (black and red, fixed-points of adaptation c(t) and firing rate ʋ(t)) superimposed to colored arrows sketching the SO. Solid black curves (left) depict attraction levels of firing rate at fixed adaptation level c (right).
(C) Bifurcation plane of the mean-field network model depicting available dynamical regimes when inhibitory strength of the adaptation feedback (determined by the conductance g) and/or an external excitatory input are changed. Yellow region, SO are spontaneously expressed. Other regions, single or bistable asynchronous states with high- and low-firing rate. Superimposed 3D landscape shows the preferred network configuration corresponding to the deepest valley.
(D) Transition from low- to high-firing asynchronous states, passing through a SO phase, in a network equivalent to the mean-field relaxation oscillator in (B and C). Inhibitory strength of adaptation is modulated in (C) by gray shaded squares. (A), (B), and (D) from Mattia and Sanchez-Vives (2012).
(E) Section of the energy landscape in (C) (dotted line in C) changing the preferred state from SO (left valley) to a more irregular asynchronous state (right valley), at different levels of anesthesia.
(F) Membrane potentials from in vivo intracellular recordings at different levels of anesthesia. From Deco et al. (2009).
Neuron  , DOI: ( /j.neuron )
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4. Figure 3 Functional Connectivity, Bistability, and Complexity
(A) Average functional connectivity matrices of rats under deep and light anesthesia. Taken from Bettinardi et al. (2015).
(B) Black traces: global mean field powers and their average in red. Right: maximum current sources, color-coded according to their latency of activation (light blue, 0 ms; red, 300 ms). Yellow cross: TMS target on the cortex.
(C) Top (LFP): cortico-cortical evoked potentials (CCEPs), the corresponding average responses from these contacts during wakefulness (left) and NREM sleep (right). Middle: event-related spectral perturbation (ERSP), time-frequency power spectra of CCEPs during wakefulness (left) and NREM sleep (right). Blue: significant reduction compared with baseline; red: significant increase. Bottom: phase-locking factor (PLF) > 8 Hz. Dashed vertical lines: stimulus onset. Taken from Pigorini et al. (2015).
Neuron  , DOI: ( /j.neuron )
Copyright © 2017 Elsevier Inc. Terms and Conditions