"What we propose is that a conscious person requires a high level of brain energy," said Robert G. Shulman, Sterling Professor Emeritus of molecular biophysics and biochemistry at Yale.
The finding has profound implications for our understanding of the connection between the brain and consciousness, Shulman said. "You can think of consciousness not as a property of the brain, but of the person."
Anesthesiologists consider a person to be in a behavioral state of consciousness when he or she can respond to simple stimuli. Properties of this state, such as the high energy and the delocalized fMRI signals, allow the person to perform the interconnected activities that make up our everyday lives. Shulman suggests that these more energetic properties of the brain support human behavior and should be considered when interpreting the much weaker signals that are typically recorded during fMRI studies.