Research finds intriguing brain wave patterns in comatose patients.
For a very long time, mysteries surrounding death and experiences during and after a person's death have challenged the minds of humans. The consequences of death on the human body and psyche have been the subject of numerous studies and trials.
Now a modest study has produced preliminary evidence of increased brain activity throughout the process of dying, which may be connected to consciousness.
Researchers from the University of Michigan in the US have discovered that two people's brains experienced an increase in activity as they approached death. This phenomenon is similar to spikes in brain activity that have previously been observed in animals whose hearts had stopped beating.
Researchers examined four individuals who died while undergoing EEG monitoring as a result of significant brain haemorrhage and anoxic damage brought on by cardiac arrest.
Following the removal of ventilator support, a spike in gamma wave activity associated with consciousness was observed in two of these patients. The "hot zone" of the brain, which is linked to dreaming and altered states of consciousness, is where this activity was found to be occurring.
Scientists from Michigan discovered that gamma oscillations became more neurophysiologically coupled and connected in the dying human brain.
"These findings prompted us to investigate the neural activity of the brain in the dying patients before and after clinical withdrawal of ventilatory support. Specifically, we examined EEG signals, by applying the computational tools used in our previous study of dying animals, with a focus on the following features: temporal dynamics of EEG power, local and long-range phase-amplitude coupling between low- and high-frequency oscillations, and functional and directed cortical connectivity across all frequency bands. All analyses were conducted with close attention to parallel changes of electrocardiogram (ECG) signals, as reported previously," Jimo Borjigin and colleagues write in their new paper.