It has been all over the popular news: a Dutch man who has not been able to move or talk for eight years due to severe brain injury can once again function normally with the use of sleeping pills. Neurobiologists Conrado Bosman and Cyriel Pennartz of the UvA’s Swammerdam Institute for Life Sciences are among the scientists behind a study that tries to unravel the working mechanism of this phenomenon. Their results are published in the journal Cortex.
The fact that a certain subset of patients with brain injury can benefit from the drug zolpidem, a GABA receptor agonist, is in itself not new. What is new is that the researchers in this study, led by the Amsterdam UMC, have found clues for the thus far unknown working mechanism behind this phenomenon. This could potentially help to find a more long-term solution for these patients. At the moment, using the sleeping drug only restores these patient’s brain functions for a short period of time.
Using electroencephalography and magnetoencephalography the scientists show that cognitive deficits, speech loss, and motor impairments after severe brain injury are associated with stronger beta band connectivity throughout the brain. Neurological recovery after zolpidem occurs with the restoration of beta band connectivity. Or, as first author Hisse Arnts of the Amsterdam UMC explained it to the media in more simple terms: the brain scans of the patients showed hyperactivity in specific parts of the brain. This hyperactivity overshadows the normal brain activity. The sleeping drug dampens the hyperactivity, thus restoring normal brain function.
Among the media that covered this story is Dutch national news agency NOS. They have an item on their website that includes footage of the now 38-year old patient, Richard, who can once again talk with the help of the sleeping drug.
Hisse Arnts et al, Awakening after a sleeping pill: Restoring functional brain networks after severe brain injury, in: Cortex, November 2020, https://doi.org/10.1016/j.cortex.2020.08.011