Open Access. Powered by Scholars. Published by Universities.®
Neuroscience and Neurobiology Commons™
Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 3 of 3
Full-Text Articles in Neuroscience and Neurobiology
Resting State Network Dynamics Across Wakefulness And Sleep, Evan Houldin
Resting State Network Dynamics Across Wakefulness And Sleep, Evan Houldin
Electronic Thesis and Dissertation Repository
The function of sleep is a longstanding mystery of the brain. By contrast, the function of resting state networks (RSNs) is one of its most recent mysteries. The relationship between RSNs and neuronal activity has been unclear since RSNs were discovered during the advent of functional magnetic resonance imaging (fMRI). Somewhat paradoxically, investigating these enigmatic phenomena in parallel can help to illuminate the function of both. The three studies described as part of this thesis all involve an evaluation of RSN dynamics across wakefulness and sleep. They are all based on the same dataset, derived from an experimental paradigm in …
A Naturalistic Paradigm To Probe Conscious Information Processing During Sleep, Max M. Silverbrook
A Naturalistic Paradigm To Probe Conscious Information Processing During Sleep, Max M. Silverbrook
Electronic Thesis and Dissertation Repository
Sleep was long considered a passive mental state. The extent to which external information is integrated in, and consciously processed during sleep remains unknown. Here, simultaneous electroencephalographic (EEG) and functional magnetic resonance imaging (fMRI) data were collected from sleeping participants. First, the stimulus elicited significantly correlated fMRI activity in the auditory and fronto-parietal networks of awake participants. Behavioural testing found individuals to perceive the story’s suspense similarly. Then neural activity related to high-level processing of the story was investigated in 5 individuals who slept through it. Fronto-parietal activity in 1 individual in rapid eye movement (REM) sleep followed that of …
Dynamic Functional Connectivity Reveals Temporal Differences In Wake And Stage-2 Sleep, Mazen El-Baba
Dynamic Functional Connectivity Reveals Temporal Differences In Wake And Stage-2 Sleep, Mazen El-Baba
Electronic Thesis and Dissertation Repository
The transition from wakefulness to sleep is marked by changes in neurophysiology, suggesting that changes in consciousness might be accompanied by changes in functional network organization. Brain activity of 21 healthy participants was measured via simultaneous EEG-fMRI as participants transitioned from wakefulness into sleep. All fMRI volumes were ICA-decomposed, yielding 42 neurophysiological sources. Independent component time courses were used to estimate mean functional connectivity (FC) and dynamic FC using a sliding window technique. Windowed matrices were submitted to k-means clustering (k = 7, L2-norm). Mean FC in Wake and Stage-2 Sleep (S2S) were similar. Dynamic analysis revealed differences in temporal …