Neural Basis of Consciousness; Functions of Sleep
Giulio Tononi is a psychiatrist and neuroscientist who has held faculty positions in Pisa, New York, San Diego and Madison, Wisconsin, where he is Professor of Psychiatry. Dr. Tononi and collaborators have pioneered several complementary approaches to study sleep. These include genomics, proteomics, fruit fly models, rodent models employing multiunit / local field potential recordings in behaving animals, in vivo voltammetry and microscopy, high-density EEG recordings and transcranial magnetic stimulation in humans, and large-scale computer models of sleep and wakefulness. This research has led to a comprehensive hypothesis on the function of sleep, the synaptic homeostasis hypothesis. According to the hypothesis, wakefulness leads to a net increase in synaptic strength, and sleep is necessary to reestablish synaptic homeostasis. The hypothesis has implications for understanding the effects of sleep deprivation and for developing novel diagnostic and therapeutic approaches to sleep disorders and neuropsychiatric disorders. Another focus of Dr. Tononi’s work is the integrated information theory of consciousness: a scientific theory of what consciousness is, how it can be measured, how it is realized in the brain and, of course, why it fades when we fall into dreamless sleep and returns when we dream. The theory is being tested with neuroimaging, transcranial magnetic stimulation, and computer models. In 2005, Dr. Tononi received the NIH Director’s Pioneer Award for his work on sleep mechanism and function, and in 2008 he was made the David P. White Chair in Sleep Medicine and is a Distinguished Chair in Consciousness Science.
- Nir Y, Tononi G. Dreaming and the brain: from phenomenology to neurophysiology. Trends in Cognitive Sciences, 14(2):88-100, 2010.
- Vyazovskiy VV, Olcese U, Lazimy YM, Faraguna U, Esser SK, Williams JC, Cirelli C, Tononi G. Cortical firing and sleep homeostasis. Neuron, 63(6):865-878, 2009.
- Balduzzi D, Tononi G. Qualia: the geometry of integrated information. PLoS Computational Biology, 5(8) e1000462:1-24, 2009.
- Gilestro GF, Tononi G, Cirelli C. Widespread changes in synaptic markers as a function of sleep and wakefulness in Drosophila. Science, 324(5923):109-12, 2009.
- Murphy M, Riedner BA, Huber R, Massimini M, Ferrarelli F, Tononi G. Source modeling sleep slow waves. Proc Natl Acad Sci U S A., 106(5):1608-13, 2009.
- Dash MB, Douglas CL, Vyazovskiy VV, Cirelli C, Tononi G. Long-term homeostasis of extracellular glutamate in the rat cerebral cortex across sleep and waking states. J Neuroscience, 29(3):620-9, 2009.
- Tononi G. Consciousness as integrated information: a provisional manifesto. Biological Bulletin, 215:216-242, 2008.
- Alkire MT, Hudetz AG, Tononi G. Consciousness and anesthesia.Science, 322:876-880, 2008.
- Tononi, G. and C. Cirelli. 2006. Sleep function and synaptic homeostasis. Sleep Med. Rev. 10: 49-62.
- Massimini, M., F. Ferrarelli, R. Huber, S.K. Esser, H. Singh, and G. Tononi. 2005. Breakdown of cortical effective connectivity during sleep. Science 309: 2228-2232
- Cirelli, C., D. Bushey, S.L. Hill, R. Huber, R. Kreber, B. Ganetzky, G. Tononi. 2005. Reduced sleep in Drosophila mutants. Nature 434: 1087-1092.
- Tononi, G. 2004. An Information Integration Theory of Consciousness. BMC Neurosci. 5: 42.
- Huber, R., M.F. Ghilardi, M. Massimini M, and G. Tononi. 2004. Local sleep and learning. Nature 430: 78-81.
- Shaw, P.J., C. Cirelli, R.J. Greenspan, and G. Tononi. 2000. Correlates of sleep and waking in Drosophila melanogaster. Science 287: 1834-1837.
- Tononi, G. and G.M. Edelman. 2000. Schizophrenia and the mechanisms of conscious integration. Brain Res. Rev. 31: 391-400.
- Tononi, G. and G.M. Edelman. 1998. Consciousness and complexity. Science 282: 1846-1851.