Sensory awareness of one's environment and the ability to recall previously stored cognitive information is central to human consciousness. J. Bruno Debruille, MD, PhD, has been conducting human research aimed at further unraveling the mysteries of consciousness in normal and in abnormal circumstances (in the case of brain damage or delusion).

A member of the Douglas Hospital Research Centre since 1997, J. Bruno Debruille has chaired and organized several international conferences on consciousness and psychophysiology. He is a fellow of the McDonnell-Pew Foundation for Cognitive Neuroscience and a scholar of the Canadian Institutes for Health Research.

The functional brain imaging technique used by Bruno Debruille is event-related evoked brain potentials (ERPs). They are the recordings of the electrical activity of the brain. As such, they are a direct index of the computations performed by the brain. This technique allows the following of the dynamics of the brain activity millisecond by millisecond.

In collaboration with Martin Lepage, J. Bruno Debruille is also using an indirect, that is, a metabolic technique: the fMRI, which has a less precise time resolution, but a spatial resolution that allows the localization of the precise brain regions that are active and responsible for particular components of the ERPs and thus, for particular components of the brain's computational activity. J. Bruno Debruille and his research team have conducted numerous studies to help explain important aspects of cognitive processing and perception.

He has studied, particularly in the case of faces, the processes that precede and permit the conscious perception. He has also studied the N400, a component of event-related brain potentials that index the processing of the knowledge previously acquired. This component appears especially interesting in the case of delusional conviction, which can exist only if the knowledge that is contradictory to the delusion can be maintained outside consciousness. The experiments conducted in Bruno Debruille’s laboratory to explore the deficits of memory in schizophrenia suggest that the brain processes generating the N400 may be involved in this maintenance.