Whether unique to humans or not, consciousness is a central aspect of our experience of the world. The neural fingerprint of this experience, however, remains one of the greatest mysteries of modern neuroscience. This issue is at the heart of one of the most challenging and least understood conditions of the human brain: the vegetative state (VS).
In the absence of an objective measure, the detection of awareness in patients relies on their ability to produce a clear sign of non-reflexive behavior. However, it has been recently estimated that up to 40% of patients diagnosed as being in a VS may in fact retain some level of consciousness. This research project employs neuroimaging to assess on the basis of brain measurements alone (i) how much cognitive function can remain after severe brain injury, and (ii) what changes in structural and functional neuroanatomy accompany the loss and recovery of consciousness.
In a recent study, in press at PLoS Computational Biology, we looked at how anesthesia affected brain function in healthy volunteers. Using a graph theoretic analysis we found that during anesthesia, brain “communication” becomes highly inefficient, making it harder for information to propagate across the brain. Efficiency in brain communication might be a central aspect to maintaining a state of consciousness:
Monti M.M., Lutkenhoff E.S., Rubinov M., Boveroux P., Vanhaudenhuyse A., Gosseries O., Bruno MA., Noirhomme Q., Boly M., Laureys S., (in press), “Dynamic change of global and local information processing in propofol-induced loss and recovery of consciousness”, PLoS Computational Biology
In a previous study, published in Human Brain Mapping, we employed fMRI to assess how much visual cognition is possible in patients who suffer from disorders of consciousness: