|The other side © Robert Sommers 2013|
The waves of death engulfed me; the currents of chaos overwhelmed me. 2 Samuel 22:5
Those that are close to me know that I have been in a very dark mood the last few weeks, if not months. What better time to discuss the wave of death? Scientists have tried in vain to understand what happens in the moments during brain death, particularly that odd 5 to 15 second period where the brain sends out a high frequency signal, perhaps signaling the mother ship for docking instructions.
From Discover.com Brain waves surge moments before death:
A study of seven terminally ill patients found identical surges in brain activity moments before death, providing what may be physiological evidence of "out of body" experiences reported by people who survive near-death ordeals.These researchers decapitated rats and found that a minute later they broadcast this high amplitude signal, a process they say might be reversible.
Doctors at George Washington University Medical Faculty Associates recorded brain activity of people dying from critical illnesses, such as cancer or heart attacks.
Moments before death, the patients experienced a burst in brain wave activity, with the spikes occurring at the same time before death and at comparable intensity and duration.
Writing in the October issue of the Journal of Palliative Medicine, the doctors theorize that the brain surges may be tied to widely reported near-death experiences which typically involve spiritual or religious attributes.
This scientific paper, Neural Dynamics during Anoxia and the “Wave of Death” offered some explanations for the occurrence.
Recent experiments in rats have shown the occurrence of a high amplitude slow brain wave in the EEG approximately 1 minute after decapitation, with a duration of 5–15 s (van Rijn et al, PLoS One 6, e16514, 2011) that was presumed to signify the death of brain neurons. We present a computational model of a single neuron and its intra- and extracellular ion concentrations, which shows the physiological mechanism for this observation. The wave is caused by membrane potential oscillations, that occur after the cessation of activity of the sodium-potassium pumps has lead to an excess of extracellular potassium. These oscillations can be described by the Hodgkin-Huxley equations for the sodium and potassium channels, and result in a sudden change in mean membrane voltage. In combination with a high-pass filter, this sudden depolarization leads to a wave in the EEG. We discuss that this process is not necessarily irreversible.
Citation: Zandt B-J, ten Haken B, van Dijk JG, van Putten MJAM (2011) Neural Dynamics during Anoxia and the “Wave of Death”. PLoS ONE 6(7): e22127. doi:10.1371/journal.pone.0022127
Editor: Olivier Baud, Hôpital Robert Debré, France
Received: May 10, 2011; Accepted: June 15, 2011; Published: July 13, 2011
Copyright: © 2011 Zandt et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Dynamic phenomena that occur during hypoxia and the way they are reflected in the EEG are only partially understood. Measurements of extreme cases showing clear features in the EEG present an opportunity to gain insight in the relation with the underlying physiology. Such an extreme case is decapitation, in which the supply of energy to the entire brain is halted almost instantaneously. This causes the EEG to become flat after several seconds, but also results in a large amplitude wave approximately a minute after decapitation. Van Rijn et al. suggest that this wave “ultimately reflects brain death” , but also state that further research on the physiology of brain function during this process is needed.
In any case, it is a curious topic. A 2002 paper in the Journal of Cellular and Molecular Medicine found that brain cells taken from a person several hours after death could survive for weeks in the lab. Scientists think the wave was evidence that the brain was on its last legs. Neurons have an electrical signal, thanks to an imbalance of positive and negative charges along their cell walls. This imbalance is called a "membrane potential." The wave of death might signal the loss of membrane potential, specifically from a mineral imbalance of sodium and potassium channels where the latter channel gets too big.
|Hot Rod Race © Robert Williams 2013|
definition of the wave of death in Urban Dictionary:
It occurs in traffic and often leads to a bad accident. One car is stopped. Another car coming in the opposite direction wants to turn left in front of the stopped car. The driver of the stopped car waves as if to say "it's OK to make the left turn in front of me". However, in the empty lane to the right of the stopped car, here comes another car whose driver has no idea that the left-turning car got the OK wave. The left-turning car and the car in the empty lane hit together usually pretty hard. Thus, the wave of death.
I was in an accident because some asshole gave another driver the wave of death.