ISBN 9783843901758

978-3-8439-0175-8, Reihe Medizin

Henning Peters
Default Mode Network Changes during NREM Sleep – a Combined EEG/fMRI Study

103 Seiten, Dissertation Ludwig-Maximilians-Universität München (2011), Softcover, A5

Zusammenfassung / Abstract

During resting wakefulness, several neuronal groups in the human brain exhibit high neural activity. Correlating time courses of active brain areas display characteristic network patterns. Amongst these resting state networks (RSN), the Default Mode Network (DMN) has become an established concept in neuroscience and received particularly strong attention and intense research.

Notably, the DMN resembles a concept of neuroradiological origin comprising a set of brain regions that were found to reduce activity when the subject is challenged by a task. In this regard, the activity of the DMN is highest during the resting condition. However, spontaneous BOLD signal fluctuations also reveal concerted activity changes in the different nodes of the DMN without particular task processing.

Various studies have confirmed the critical contribution of the DMN to human functioning and its relevance for the interaction between internal mentation and external attention. Involved in autobiographical memory, envisioning the future and theory of mind, it is thought to reflect processes of information integration from monitoring the environment and evaluate sensorial input for individual relevance to oneself.

This dissertation presents alterations of the DMN and its anti-correlated network (ACN), which is activated during external attention, throughout natural human nonrapid eye movement sleep (NREM). The study of the relation of the DMN to sleep is of particular interest, since falling asleep is paralleled by loss of consciousness and reduced internal and external awareness. We used combined functional magnetic resonance imaging (fMRI) and electroencephalographic (EEG) recordings of 25 healthy, young adult subjects.