Altered overnight modulation of spontaneous waking EEG reflects altered sleep homeostasis in major depressive disorder: A high-density EEG investigation

Abstract

Background Prior investigations have suggested sleep homeostasis is altered in major depressive disorder (MDD). Low frequency activity (LFA) in the electroencephalogram during waking has been correlated with sleep slow wave activity (SWA), suggesting that waking LFA reflects sleep homeostasis in healthy individuals. This study investigated whether the overnight change in waking LFA and its relationship with sleep SWA are altered in MDD. Methods 256-channel high-density electroencephalography (hdEEG) recordings during waking (pre- and post-sleep) and during sleep were collected in 14 unmedicated, unipolar MDD subjects (9 women) and age- and sex-matched healthy controls (HC). Results Waking LFA (3.25–.25 Hz) declined significantly overnight in the HC group, but not in the group of MDD subjects. Overnight decline of waking LFA correlated with sleep SWA in frontal brain regions in HC, but a comparable relationship was not found in MDD. Limitations This study is not able to definitely segregate overnight changes in the waking EEG that may occur due to homeostatic and/or circadian factors. Conclusions MDD involves altered overnight modulation of waking low frequency EEG activity that may reflect altered sleep homeostasis in the disorder. Future research is required to determine the functional significance and clinical implications of these findings.

Neurofeedback Tunes Scale-Free Dynamics in Spontaneous Brain Activity

“…Crucially, this was paralleled by a decrease in synchronization variability during sleep deprivation, which was rescued to baseline levels post-sleep (Meisel et al 2013). This may be interpreted as initial evidence for homeostatic regulation (i.e., self-tuning) of critical brain dynamics, a dynamic mechanism that appears to be compromised in psychiatric disorder (Plante et al 2013). Hence, our results complement emerging work by revealing a self-tuning of spontaneous brain oscillations plus LRTCs on much briefer timescales (<1h) and in the absence of sleep, supporting findings that neuronal homeostasis may also occur during waking states (Hengen et al 2016).…”

Tuning pathological brain oscillations with neurofeedback: a systems neuroscience framework

“…A related phenomenon is the spectral over-synchronization frequently seen following mental fatigue (Huang et al, 2008 ) or sleep deprivation (Gorgoni et al, 2014 ), understood to be the product of increases in local experience-dependent plasticity (Hung et al, 2013 ). Subsequently, following sleep, the EEG is miraculously restored to a less synchronized state the day after (Plante et al, 2013 ). Fascinatingly, this latter process seems to be compromised in psychiatric disorder (Plante et al, 2013 ).…”

“…Subsequently, following sleep, the EEG is miraculously restored to a less synchronized state the day after (Plante et al, 2013 ). Fascinatingly, this latter process seems to be compromised in psychiatric disorder (Plante et al, 2013 ). Tying all this evidence together appears to lead to a beautifully parsimonious conclusion: it is neither high nor low synchronization that may be critical, but rather a golden balance in-between.…”

An Integrated Model of Slow-Wave Activity and Neuroplasticity Impairments in Major Depressive Disorder

“…The authors interpreted these findings as further evidence of homeostatic impairments in depression. Additionally, Plante and colleagues [19] demonstrated that low-frequency activity from the waking EEG, a marker of sleep propensity and the homeostatic drive for sleep, likewise decreased following sleep in healthy controls, and did not change in those with MDD. Taken together, while the mechanism is still not clearly understood, results from several studies provide some support for the idea that those with MDD have impaired sleep homeostasis, generally, and perhaps a deficiency of process S, more specifically.…”

“…As previously discussed, the homeostatic regulation of sleep has been shown to be impaired in those with MDD [7, 18, 19]. The degree of this impairment, as indexed by SWA dissipation, has also been linked to mood disturbance [23•], such that the less dissipation of SWA, indicative of more impaired homeostatic regulation, the more mood is disturbed.…”