Disrupted directed connectivity along the cingulate cortex determines vigilance after sleep deprivation

Abstract

The cingulate cortex is regarded as the backbone of structural and functional connectivity of the brain. While its functional connectivity has been intensively studied, little is known about its effective connectivity, its modulation by behavioral states, and its involvement in cognitive performance. Given their previously reported effects on cingulate functional connectivity, we investigated how eye-closure and sleep deprivation changed cingulate effective connectivity, estimated from resting-state high-density electroencephalography (EEG) using a novel method to calculate Granger Causality directly in source space. Effective connectivity along the cingulate cortex was dominant in the forward direction. Eyes-open connectivity in the forward direction was greater compared to eyes-closed, in well-rested participants. The difference between eyes-open and eyes-closed connectivity was attenuated and no longer significant after sleep deprivation. Individual variability in the forward connectivity after sleep deprivation predicted subsequent task performance, such that those subjects who showed a greater increase in forward connectivity between the eyes-open and the eyes-closed periods also performed better on a sustained attention task. Effective connectivity in the opposite, backward, direction was not affected by whether the eyes were open or closed or by sleep deprivation. These findings indicate that the effective connectivity from posterior to anterior cingulate regions is enhanced when a well-rested subject has his eyes open compared to when they are closed. Sleep deprivation impairs this directed information flow, proportional to its deleterious effect on vigilance. Therefore, sleep may play a role in the maintenance of waking effective connectivity.

Encephalography Connectivity on Sources in Male Nonsmokers after Nicotine Administration during the Resting State

“…1a, b) is in line with previous findings that reported EO connectivity in the forward direction to be greater compared to EC [2]. As a caveat, there are differences between the present article and the findings of Piantoni et al [2], specifically the frequency range, algorithm used for computing connectivity, and the number and location of the estimated sources. Nonetheless, the authors believe the pattern that emerged in the present study is consistent with the discovery presented in their report.…”

“…Figure 1b illustrates the significant increase in feedforward connectivity under EO as compared to EC. An increase of feedforward connectivity by comparing EC with respect with EO was also found in a previous study [2]. …”

“…EO vs. EC differences), then it should also be possible to gauge the drug effects. The validation of the rPDC pipeline aimed at replicating the findings of Piantoni et al [2]. Almost all results of the t test were statistically significant.…”

“…An example is the use of connectivity measures that provide a unique perspective on the interaction of oscillatory brain dynamics [1]. Particularly interesting is the use of connectivity measures of oscillatory electromagnetic activity regarding the modulation of vigilance [2]. Indeed, there has been recent interest in directed connectivity detected by renormalized partial directed coherence (rPDC), with a particular emphasis on the pharmacological modifications of vigilance [3] by using encephalography (EEG).…”

Long-term total sleep deprivation reduces thalamic gray matter volume in healthy men

“…It has been demonstrated that sleep loss can reduce performance on a broad variety of tasks and affects brain functional activity [7,8]. Nevertheless, no previous study has examined the effects of sleep loss on gray matter (GM) structures in healthy adults.…”