Spontaneous brain activity fluctuations: insights from states of diminished conscious awareness

ENZO TAGLIAZUCCHI

Estocolmo

Simposio; Imaging the Sleepy Brain; 2014

Instituto Karolinska

In recent years we have seen a flood of papers studying intrinsic brain activity during wakeful rest ("resting state") and its use as a tool to understand brain function, as well as to develop biomarkers for different diseases. In spite of many interesting results, there is little consensus about the answer to very basic questions regarding these spontaneous, intrinsic brain activity fluctuations. What is their origin? What is their function? How are they related to unrestrained ongoing cognition? In this talk, we will first present many different plausible answers to these questions, and we will then show what we can learn about them by the study of brain activity during the different states of awareness we experience as we fall into deep sleep. As a result of these studies, we expect to gain insights not only on resting state brain activity during wakefulness, but also on the mechanisms which underlie loss of consciousness in the descent to deep sleep. Furthermore, taking into account the possibility of sleep during resting state experiments will lead to redefine the brain state associated with spontaneous activity, prompting a major re-evaluation of a number of already published results.