A new study, published on Nature Nueroscience in August, demonstrates that at least the half of the sleep promoting activity of the brain originates in the Parafacial Zone (PZ), located in the brain stem. Specifically, Christelle Anaclet (Harvard Medical School and University of Buffalo) and her staff, found that the GABAergic neurons, in this brain area, are responsible for deep sleep. The innovation in Anaclet’s research is the use of new techniques that allow the reserachers to control in a remote way the activity of the gabaergic neurons, by turning them on or off on demand. That is to say that this staff could control specific cellular activities in a refined way. Dr Anclet herself says: “Before these tools were developed, we often used ‘electrical stimulation’ to activate a region, but the problem is that doing so stimulates everything the electrode touches and even surrounding areas […]. It was a sledgehammer approach, when what we needed was a scalpel.” The staff, in order to achieve the precision required at a molecular level, introduced a special virus in the Parafacial Zone capable of expressing a “designer receptor” only on GABAergic neurons, without altering brain functions. When the researchers turned on the GABA neurons in the PZ, the animal quickly fell into a deep sleep. This outcome demonstrates that the GABAergic neurons in the PZ are heavily involved in deep sleep process. Actually the use of “designer genes” (genes created or altered by genetic engineering) gives neuroscientists the ability to control the brain in a new special way, according to their specific needs. This precision may lead to very important implications at a clinical level, with new discoveries for the treatment of pathologies like insomnia and sleep disorders. It remains to study and understand how these neurons interact with other sleep and wake promoting regions of the brain, but with these new tools we are confident of new important findings. More information on: Nature Neuroscience, Published online August 17 2014 doi:10.1038/nn.3789 – “The GABAergic parafacial zone is a medullary slow wave sleep–promoting center”, by Christelle Anaclet et al. Dr. Lorena Angela Cattaneo Psychopathologist Expert in Clinical Neuroscience of Behavior