It Works, But How? MCW Researchers to Study Mechanisms of Anesthesia

Published on: 8/14/2013

The Medical College of Wisconsin (MCW) has received a four year, $1.3 million grant from the National Institutes of Health’s National Institute of General Medical Sciences to study how anesthesia works to suppress consciousness, and how consciousness returns.

Anthony Hudetz, DBM, PhD, professor of anesthesiology, physiology and biophysics; and Shi-Jiang Li, PhD, professor of biophysics; are the principal investigators of the grant. Jeffrey Binder, MD, professor of neurology; and Kathryn Lauer, MD, professor of anesthesiology are co-investigators.

Although general anesthesia has been used safely for over 160 years, how exactly anesthetic agents modulate the state of consciousness has been a mystery, as is the neural basis of human consciousness. The overall goal of this project is to understand the neural mechanisms by which general anesthetics suppress consciousness and allow its return during emergence in the human brain. The researchers hypothesize that consciousness emerges from the functional connectivity of large-scale networks in the brain, and that general anesthetics suppress consciousness by disrupting those networks. In this project, the research team will use blood-oxygen level-dependent functional MRI (fMRI) to assess the effects of propofol, a general anesthetic, in the brain of human participants. The work should reveal the order in which cognitive functions are lost during sedation and anesthesia and return during awakening.

The project should advance understanding of the neural mechanisms of anesthesia and the ways in which it impacts brain connectivity. The results should also help develop novel fMRI-based approaches for an assessment of the level of mental functioning in patients with suppressed consciousness. In a wider context, the findings should increase overall understanding of the scientific basis of human consciousness.