Giulio Tononi is a professor of psychiatry at the University of Wisconsin. He is an authority on sleep, and in particular the genetics and etiology

Etiology

Etiology is the study of causation, or origination. The word is derived from the Greek , aitiologia, "giving a reason for" ....

 of sleep.
He is also interested in the nature of consciousness,

and has co-authored a book on the subject with Gerald Edelman

Gerald Edelman

Gerald Maurice Edelman is an American biologist who shared the 1972 Nobel Prize in Physiology or Medicine for work with Rodney Robert Porter on the immune system. Edelman's Nobel Prize-winning research concerned discovery of the structure of antibody molecules...

.

He also developed Integrated Information Theory (IIT)

Integrated Information Theory (IIT)

The Integrated Information Theory is a recently formulated theory which attempts to quantitatively measure consciousness. It was developed by psychiatrist and neuroscientist Giulio Tononi of the University of Wisconsin–Madison.- Overview :...

 as a quantitative measure of consciousness.

His work has been described as "the only really promising fundamental theory of consciousness" by Christof Koch

Christof Koch

Christof Koch is an American neuroscientist working on the neural basis of consciousness. He is the Lois and Victor Troendle Professor of Cognitive and Behavioral Biology at California Institute of Technology, where he has been since 1986...

.