Winston Chiong led a journal club discussion about a recent Nature comment written by Nita Farahany, Henry Greely, and Charles Giattino in response to a Yale study, called BrainEx, in which investigators restored and preserved some cellular functions, from microcirculation to spontaneous synaptic activity, in whole pig brains that were perfused four hours after death. Our group discussed implications the BrainEx study may have for future research and clinical applications. Winston also shared his perspective as a member of the NIH Neuroethics Working Group, who consulted the study investigators on ethical research conduct.
We considered how future access to whole-brain models may contribute to medicine and neuroscience, for example, by aiding stroke research and enabling deeper investigation into the structural organization of the brain than currently feasible using neural tissues and cells. A potentially revolutionary tool, the BrainEx perfusion system and its success in restoring limited function to post-mortem brains challenges a widely-held notion that brains incur irreversible damage within seconds to minutes of blood flow disruption; although there was already substantial clinical evidence to suggest that this view was outdated. Brain models like those in BrainEx raise troubling questions questions regarding moral status and sentience. We wondered if perfusion closer to time of death might enable restoration of more complex capacities, such as consciousness and pain perception, and if so, how researchers ought to detect (e.g., EEG, TMS) and suppress (e.g., anesthetics, neuronal activity blockers) their presence. We also discussed how partial restoration of brain function might impact public understanding of brain death, the future of organ donation and transplantation, and animal welfare laws, which presently do not protect research specimens obtained from animals raised for food production.