Giulio Tononi

Position title: Professor


Phone: (608) 263-6063

Giulio Tononi headshot



M.D., University of Pisa, Italy

Ph.D. in Neuroscience, Scuola Superiore di Studi Universitari e di Perfezionamento S. Anna, Italy

Research Description:

Dr. Giulio Tononi is Professor of Psychiatry, Distinguished Professor in Consciousness Science, the David P. White Chair in Sleep Medicine at the University of Wisconsin-Madison, and the Director of the Wisconsin Institute for Sleep and Consciousness. His laboratory studies consciousness and its disorders as well as the mechanisms and functions of sleep. Dr. Tononi’s main contribution in the study of consciousness has been the development of the integrated information theory. This is a comprehensive theory of what consciousness is, what determines its quantity and quality, and how it emerges from causal structures such as neural networks. The theory provides a parsimonious account of many neuropsychological observations, among them why certain parts of the brain give rise to experience and others do not, why consciousness vanishes during slow wave sleep and seizures despite continuing neural activity, and how unconscious processes interact with conscious ones. The theory has implications for the unfolding of consciousness across development and phylogeny, and predicts which ingredients are necessary and sufficient to construct sentient machines. With regard to the study of sleep, Dr. Tononi’s main contribution has been the development of a comprehensive hypothesis about the function of sleep, the synaptic homeostasis hypothesis. According to the hypothesis, sleep serves to renormalize synaptic strength, counterbalancing a net increase of synaptic strength due to plasticity during wakefulness. Without sleep, such progressive increase in synaptic strength would lead to unsustainable costs in terms of energy, space, cellular supplies, and would saturate the ability to learn. In short, sleep is the price to pay for plasticity during wakefulness.

Key Words:

Consciousness, integrated information theory, disorders of consciousness, mechanisms and functions of sleep, synaptic homeostasis hypothesis

Link to Lab Website

Link to Lab Website (Medicine)

Link to Publications